JP7426051B2 - Construction method of temporary cofferdam structure - Google Patents

Description

The present invention relates to a method for constructing a temporary cofferdam structure to be constructed when repairing, reinforcing, or otherwise renovating an underwater structure such as a bridge pier installed underwater in a river or the sea.

Conventionally, underwater structures such as bridge piers installed underwater in rivers, oceans, etc. are repaired by methods such as concrete wrapping or aramid fiber wrapping when damage occurs due to aging, typhoons, earthquakes, etc. At that time, in order to secure a working space, it is necessary to create a dry environment around the underwater structure without water. This dry environment is created by constructing cylindrical temporary cofferdam structures at predetermined intervals around the underwater structure and excluding water from inside the cofferdam structures. In general, construction of this temporary cofferdam structure involves the underwater work of divers who install multiple members such as liner plates that can be connected to each other in the upper, lower, and circumferential directions of the underwater structure in a cylindrical shape around the underwater structure. This is done by placing them on the ground and connecting them using bolts and nuts. (For example, see Patent Document 1).

However, in the above-mentioned prior art, there are points that should be improved as described below.

In other words, when constructing a temporary cofferdam structure, when connecting members such as liner plates, which are the main structural members, in order to reduce water leakage from the connecting parts, water-stop packing is interposed between them, and bolts and It was necessary to tighten the nut firmly. When performing connection work underwater, divers have to work in an unstable position, so when assembling the water-stop gasket, there is a problem in that it is easily damaged and causes water leakage. Furthermore, since the bolts and nuts are strongly tightened, there is a problem in that the liner plate becomes deformed and becomes difficult to reuse.

Japanese Patent Application Publication No. 11-21908

The present invention was devised under the above-mentioned circumstances, and provides a temporary cofferdam structure that can prevent water leakage with simple work and that makes it easy to reuse the liner plate, which is the main component. It is an object of the present invention to provide a construction method for a temporary cofferdam structure that can be constructed efficiently.

A method for constructing a temporary cofferdam structure provided by a first aspect of the present invention is a method for constructing a temporary cofferdam structure constructed around an underwater structure, wherein the temporary cofferdam structure is a temporary cofferdam structure. a construction step of constructing the temporary cofferdam structure body around the underwater structure; and a construction step of constructing the temporary cofferdam structure body around the underwater structure; a covering step of covering an outer surface of the structure main body with the waterproof cover, the temporary cofferdam structure main body includes an assembly intermediate assembled around the underwater structure , and the construction step includes: a first state that can changeably assume a contracted and expanded state around the underwater structure , on which the assembly intermediate can be assembled and held in air; a work platform installation step of installing a work platform at a predetermined height so as to surround the underwater structure; an assembly step of bringing the work platform into the first state and assembling the assembly intermediate; a lowering step of bringing the work platform into the second state and lowering the assembly intermediate into water; and a lowering step of lowering the assembly intermediate into water. When the assembly intermediate body is placed at the lowest level of the temporary cofferdam structure main body, the assembly process includes an installation step of installing the assembly intermediate body on the foundation of the underwater structure , the assembly process, and the lowering process. a laminating step of laminating the assembly intermediate bodies until the temporary cofferdam structure body reaches a desired height by repeating the process as necessary, and the waterproof cover includes at least one waterproof sheet; water leakage prevention joining means for opening and closing the joint formed between the sheet ends of the at least one waterproof sheet so as to prevent water leakage from the joint , and the covering step includes: When the assembly intermediate body is an assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body, a waterproof sheet attachment part is provided at a predetermined location of the assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body. a step of installing a waterproof sheet attachment part; and arranging the at least one waterproof sheet along the circumferential direction of the temporary cofferdam structure body so as to form the joint between the sheet ends of the at least one waterproof sheet. a waterproof sheet attaching step of attaching a lower part of the at least one waterproof sheet to the waterproof sheet attachment part; and a step of attaching the lower part of the at least one waterproof sheet to the temporary cofferdam structure main body with the upper part of the at least one waterproof sheet being opened. a temporary fixing step of temporarily fixing the at least one waterproof member temporarily fixed to the temporary fixing portion in water; The method further includes a joining step of removing the upper part of the sheet from the temporary fixing part and joining the joint upwardly while closing the water leakage prevention joining means.

Preferably, the waterproof sheet attaching part installation step, the waterproof sheet attaching step, and the temporary fixing step are performed in parallel with the assembling step in air.

Preferably, the at least one waterproof sheet is configured to float or float in water, and in the joining step, after the at least one waterproof sheet is removed from the temporary fixing part, the at least one waterproof sheet floats or floats in water. The structure is such that the joints are joined while moving the joints.

Preferably, in the temporary fixing step, the upper part of the at least one waterproof sheet is rolled up into a rolled body or a folded body folded into a bellows shape, with the water leakage prevention joining means being opened. It is configured to be temporarily fixed to the temporary fixing part.

Preferably, the water leakage prevention joining means is a waterproof fastener provided at the joint, and in the joining step, the joint is joined by closing the waterproof fastener.

Preferably, in the assembling step, the wall portion of the pre-assembly intermediate body is formed by connecting liner plates in the circumferential direction and the vertical direction, and in the waterproof sheet attaching portion installation step, the wall portion of the temporary cofferdam structure main body is formed. The waterproof sheet attachment part is installed at the predetermined location on the wall of the assembly intermediate body disposed at the lower part using H-shaped steel, and in the waterproof sheet attachment step, the flange part of the H-shaped steel is installed. The lower part of the at least one waterproof sheet is attached using bolts or clamps.

Preferably, in the assembling step, the liner plate is connected to the portion covered by the waterproof cover without intervening a band-shaped waterproof packing.

Preferably, the method further includes an underwater concrete placing step of placing underwater concrete for water-stopping inside the assembly intermediate installed on the foundation of the underwater structure , and in the underwater concrete placing step, The underwater concrete is placed so that the upper surface of the underwater concrete is at the same height as or higher than the waterproof sheet attachment part.

A method for constructing a temporary cofferdam structure provided by a second aspect of the present invention is a method for constructing a temporary cofferdam structure constructed around an underwater structure, wherein the temporary cofferdam structure is a temporary cofferdam structure. a construction step of constructing the temporary cofferdam structure body around the underwater structure; and a construction step of constructing the temporary cofferdam structure body around the underwater structure; a covering step of covering an outer surface of the structure main body with the waterproof cover, the temporary cofferdam structure main body includes an assembly intermediate assembled around the underwater structure , and the construction step includes: a first state that can changeably assume a contracted and expanded state around the underwater structure , on which the assembly intermediate can be assembled and held in air; a work platform installation step of installing a work platform at a predetermined height so as to surround the underwater structure; an assembly step of bringing the work platform into the first state and assembling the assembly intermediate; a lowering step of bringing the work platform into the second state and lowering the assembly intermediate into water; and a lowering step of lowering the assembly intermediate into water. When the assembly intermediate body is placed at the lowest level of the temporary cofferdam structure main body, the assembly process includes an installation step of installing the assembly intermediate body on the foundation of the underwater structure , the assembly process, and the lowering process. a laminating step of laminating the assembly intermediate bodies until the temporary cofferdam structure body reaches a desired height by repeating the process as necessary, and the waterproof cover includes at least one waterproof sheet; water leakage prevention joining means for opening and closing the joint formed between the sheet ends of the at least one waterproof sheet so as to prevent water leakage from the joint , and the covering step includes: When the assembly intermediate body is an assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body, a waterproof sheet attachment part is provided at a predetermined location of the assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body. a step of installing a waterproof sheet attachment part; and arranging the at least one waterproof sheet along the circumferential direction of the temporary cofferdam structure body so as to form the joint between the sheet ends of the at least one waterproof sheet. a waterproof sheet attaching step of attaching a lower part of the at least one waterproof sheet to the waterproof sheet attachment part; and a step of attaching the lower part of the at least one waterproof sheet to the temporary cofferdam structure main body with the upper part of the at least one waterproof sheet being opened. a temporary fixing step of temporarily fixing the upper part of the at least one waterproof sheet to a temporary fixing part provided on the assembly intermediate body disposed at the lower part, and the covering step includes fixing the upper part of the at least one waterproof sheet to the temporary cofferdam structure body an additional temporary fixing step of temporarily fixing to an additional temporary fixing part provided above the temporary fixing part, releasing the temporary fixing of the upper part of the at least one waterproof sheet, and closing the water leakage prevention joining means. a joining step of joining the joint toward the additional temporary fixing portion, and repeating the additional temporary fixing step and the joining step as necessary, thereby joining the joint in stages. The method is characterized by further comprising a step.

A method for constructing a temporary cofferdam structure provided by a third aspect of the present invention is a method for constructing a temporary cofferdam structure constructed around an underwater structure, wherein the temporary cofferdam structure is a temporary cofferdam structure. a construction step of constructing the temporary cofferdam structure body around the underwater structure; and a construction step of constructing the temporary cofferdam structure body around the underwater structure; a covering step of covering an outer surface of the structure main body with the waterproof cover, the temporary cofferdam structure main body includes an assembly intermediate assembled around the underwater structure , and the construction step includes: a first state that can changeably assume a contracted and expanded state around the underwater structure , on which the assembly intermediate can be assembled and held in air; a work platform installation step of installing a work platform at a predetermined height so as to surround the underwater structure; an assembly step of bringing the work platform into the first state and assembling the assembly intermediate; a lowering step of bringing the work platform into the second state and lowering the assembly intermediate into water; and a lowering step of lowering the assembly intermediate into water. When the assembly intermediate body is placed at the lowest level of the temporary cofferdam structure main body, the assembly process includes an installation step of installing the assembly intermediate body on the foundation of the underwater structure , the assembly process, and the lowering process. a laminating step of laminating the assembly intermediate bodies until the temporary cofferdam structure body reaches a desired height by repeating the process as necessary, and the waterproof cover includes at least one waterproof sheet; water leakage prevention joining means for opening and closing the joint formed between the sheet ends of the at least one waterproof sheet so as to prevent water leakage from the joint , and the covering step includes: When the assembly intermediate body is an assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body, a waterproof sheet attachment part is provided at a predetermined location of the assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body. a step of installing a waterproof sheet attachment part; and arranging the at least one waterproof sheet along the circumferential direction of the temporary cofferdam structure body so as to form the joint between the sheet ends of the at least one waterproof sheet. a tarpaulin attaching step of attaching a lower part of the at least one tarpaulin sheet to the tarpaulin attachment part; and a tarpaulin attaching step of attaching the lower part of the at least one tarpaulin sheet to the tarpaulin attachment part, and attaching the upper part of the at least one tarpaulin sheet to a predetermined location of the work platform with the leakage prevention joint means open. a temporary fixing step of temporarily fixing it to a provided temporary fixing part so that it can be drawn out from the work platform, and in the lowering step, an assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body is lowered. The upper part of the at least one waterproof sheet is lowered while being paid out from the work platform, and the covering step is a joining step of joining the joint upwardly while closing the leakage prevention joining means underwater. It is characterized by further having the following.

A construction method of a temporary cofferdam structure provided by a fourth aspect of the present invention is a construction method of a temporary cofferdam structure constructed around an underwater structure, wherein the temporary cofferdam structure is a temporary cofferdam structure. a construction step of constructing the temporary cofferdam structure body around the underwater structure; and a construction step of constructing the temporary cofferdam structure body around the underwater structure; a covering step of covering an outer surface of the structure main body with the waterproof cover, the temporary cofferdam structure main body includes an assembly intermediate assembled around the underwater structure , and the construction step includes: a first state that can changeably assume a contracted and expanded state around the underwater structure , on which the assembly intermediate can be assembled and held in air; a work platform installation step of installing a work platform at a predetermined height so as to surround the underwater structure; an assembly step of bringing the work platform into the first state and assembling the lowermost assembly intermediate on the work platform when the assembly intermediate is the lowermost assembly intermediate; 2, and a lowering step of lowering an additional assembly intermediate among the assembly intermediates onto it using the lowermost assembly intermediate as a support to a height where it can be assembled in the air, and assembling the lowermost stage. an additional assembly step of assembling the additional assembly intermediate thereon using the intermediate as the support; and, if necessary, the lowering step until the lowermost assembly intermediate reaches the bottom of the underwater structure. and an installation step of installing the lowermost assembly intermediate that has landed on the bottom on the foundation of the underwater structure . , the waterproof cover includes at least one waterproof sheet and a water leak prevention joint that connects the seam formed between the sheet end portion of the at least one waterproof sheet so as to be openable and closable so as to prevent water from leaking from the seam. means, the covering step includes a waterproof sheet attachment part installation step of providing a waterproof sheet attachment part at a predetermined location of the assembly intermediate body disposed below the temporary cofferdam structure main body among the assembly intermediate bodies. , the at least one waterproof sheet is arranged along the circumferential direction of the temporary cofferdam structure body so as to form the seam between the sheet ends of the at least one waterproof sheet, a tarpaulin attachment step of attaching a lower part of the sheet to the tarpaulin attachment part; and an assembly in which the upper part of the at least one tarpaulin sheet is placed at the lower part of the temporary cofferdam structure body with the leakage prevention joining means open. a temporary fixing step of temporarily fixing the upper part of the at least one waterproof sheet temporarily fixed to the temporary fixing section in water; The invention is characterized by further comprising a joining step of releasing the water leakage prevention joining means and joining the joint upwardly while closing the water leakage prevention joining means.

A construction method of a temporary cofferdam structure provided by a fifth aspect of the present invention is a construction method of a temporary cofferdam structure constructed around an underwater structure, wherein the temporary cofferdam structure is a temporary cofferdam structure. a construction step of constructing the temporary cofferdam structure body around the underwater structure; and a construction step of constructing the temporary cofferdam structure body around the underwater structure; a covering step of covering an outer surface of the structure main body with the waterproof cover, the temporary cofferdam structure main body includes an assembly intermediate assembled around the underwater structure , and the construction step includes: a first state that can changeably assume a contracted and expanded state around the underwater structure , on which the assembly intermediate can be assembled and held in air; a work platform installation step of installing a work platform at a predetermined height so as to surround the underwater structure; an assembly step of bringing the work platform into the first state and assembling the lowermost assembly intermediate on the work platform when the assembly intermediate is the lowermost assembly intermediate; 2, and a lowering step of lowering an additional assembly intermediate among the assembly intermediates onto it using the lowermost assembly intermediate as a support to a height where it can be assembled in the air, and assembling the lowermost stage. an additional assembly step of assembling the additional assembly intermediate thereon using the intermediate as the support; and, if necessary, the lowering step until the lowermost assembly intermediate reaches the bottom of the underwater structure. and an installation step of installing the lowermost assembly intermediate that has landed on the bottom on the foundation of the underwater structure . , the waterproof cover includes at least one waterproof sheet and a water leak prevention joint that connects the seam formed between the sheet end portion of the at least one waterproof sheet so as to be openable and closable so as to prevent water from leaking from the seam. means, the covering step includes a waterproof sheet attachment part installation step of providing a waterproof sheet attachment part at a predetermined location of the assembly intermediate body disposed below the temporary cofferdam structure main body among the assembly intermediate bodies. , the at least one waterproof sheet is arranged along the circumferential direction of the temporary cofferdam structure body so as to form the seam between the sheet ends of the at least one waterproof sheet, a tarpaulin attachment step of attaching a lower part of the sheet to the tarpaulin attachment part; and an assembly in which the upper part of the at least one tarpaulin sheet is placed at the lower part of the temporary cofferdam structure body with the leakage prevention joining means open. a temporary fixing step of temporarily fixing the upper part of the at least one waterproof sheet to a temporary fixing part provided on the intermediate body; an additional temporary fixing step of temporarily fixing the at least one waterproof sheet to an additional temporary fixing part provided above, and releasing the temporary fixing of the upper part of the at least one waterproof sheet, and closing the water leakage prevention joining means while closing the additional temporary fixing part. The method further includes a joining step of joining the joints toward the desired position, and a repeating step of joining the joints in stages by repeating the additional temporary fixing step and the joining step as necessary. It is characterized by

A method for constructing a temporary cofferdam structure provided by a sixth aspect of the present invention is a method for constructing a temporary cofferdam structure constructed around an underwater structure, wherein the temporary cofferdam structure is a temporary cofferdam structure. a construction step of constructing the temporary cofferdam structure body around the underwater structure; and a construction step of constructing the temporary cofferdam structure body around the underwater structure; a covering step of covering an outer surface of the structure main body with the waterproof cover, the temporary cofferdam structure main body includes an assembly intermediate assembled around the underwater structure , and the construction step includes: a first state that can changeably assume a contracted and expanded state around the underwater structure , on which the assembly intermediate can be assembled and held in air; a work platform installation step of installing a work platform at a predetermined height so as to surround the underwater structure; an assembly step of bringing the work platform into the first state and assembling the lowermost assembly intermediate on the work platform when the assembly intermediate is the lowermost assembly intermediate; 2, and a lowering step of lowering an additional assembly intermediate among the assembly intermediates onto it using the lowermost assembly intermediate as a support to a height where it can be assembled in the air, and assembling the lowermost stage. an additional assembly step of assembling the additional assembly intermediate thereon using the intermediate as the support; and, if necessary, the lowering step until the lowermost assembly intermediate reaches the bottom of the underwater structure. and an installation step of installing the lowermost assembly intermediate that has landed on the bottom on the foundation of the underwater structure . , the waterproof cover includes at least one waterproof sheet and a water leak prevention joint that connects the seam formed between the sheet end portion of the at least one waterproof sheet so as to be openable and closable so as to prevent water from leaking from the seam. means, the covering step includes a waterproof sheet attachment part installation step of providing a waterproof sheet attachment part at a predetermined location of the assembly intermediate body disposed below the temporary cofferdam structure main body among the assembly intermediate bodies. , the at least one waterproof sheet is arranged along the circumferential direction of the temporary cofferdam structure body so as to form the seam between the sheet ends of the at least one waterproof sheet, a tarpaulin attachment step of attaching a lower part of the sheet to the tarpaulin attachment part, and a step of attaching the upper part of the at least one tarpaulin sheet to a temporary fixing part provided at a predetermined location of the work platform with the water leakage prevention joining means open. a temporary fixing step of temporarily fixing it so that it can be drawn out from a work platform, and in the lowering step, when lowering the assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body, the at least one The upper part of the waterproof sheet is lowered while being paid out from the work platform, and the covering step further includes a joining step of joining the joints upward while closing the leakage prevention joining means underwater. It is said that

According to the present invention, a method for constructing a temporary cofferdam structure can efficiently perform construction of a temporary cofferdam structure in which water leakage can be prevented with simple work and the liner plate, which is a main component, can be easily reused. can be provided.

Other features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings.

FIG. 1 is a perspective view showing a float platform according to a first embodiment of the present invention. 2 is a sectional view taken along line II-II in FIG. 1. FIG. FIG. 2 is a perspective view of the float platform shown in FIG. 1 in an expanded state; 4 is a cross-sectional view taken along line IV-IV in FIG. 3. FIG. FIG. 5(A) is a perspective view showing an example of a float segment forming the float platform of FIG. 1. FIG. FIG. 5(B) is an exploded front view and an exploded plan view showing details of the VB portion of FIG. 5(A). FIG. 6(A) is a perspective view showing a connecting portion of two adjacent float segments included in the float platform of FIG. 1. FIG. FIG. 6(B) is a cross-sectional view taken along line VIB-VIB in FIG. 6(A). FIG. 6(C) is a sectional view showing a state in which the connecting portions of the two float segments shown in FIG. 6(B) are open. FIG. 7 is a perspective view showing an example of a temporary cofferdam structure constructed using the float platform shown in FIG. 1. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 7. FIG. 8 is a sectional view taken along line IX-IX in FIG. 7. FIG. FIG. 10(A) is a perspective view showing an example of a liner plate included in the temporary cofferdam structure shown in FIG. 7. FIG. FIG. 10(B) is a cross-sectional view taken along the line XB-XB in FIG. 10(A). FIG. 11(A) is an exploded sectional view in a plan view showing a connection portion between left and right liner plates included in the temporary cofferdam structure shown in FIG. 7. FIG. Similarly, FIG. 11(B) is an exploded cross-sectional view from the left side showing the connecting portion of the upper and lower liner plates. FIG. 11(C) is an exploded front view of the temporary cofferdam structure seen from the inside, showing the connecting portions of the upper, lower, left, and right liner plates. FIG. 12(A) is a perspective view showing an example of a reinforcing member used to attach the waterproof sheet included in the temporary cofferdam structure shown in FIG. 7. FIG. 12(B) is a perspective view showing an example of reinforcing members arranged for each predetermined number of layers of vertically stacked liner plates included in the temporary cofferdam structure shown in FIG. FIG. 13(A) is an exploded cross-sectional view from the left side showing a connecting portion between the liner plate included in the temporary cofferdam structure shown in FIG. 7 and the reinforcing member shown in FIG. 12(A). FIG. 13(B) is a front view showing the splint of the reinforcing member shown in FIG. 12(A). FIG. 13(C) is a front view showing a connecting portion between reinforcing members shown in FIG. 12(A). FIG. 13(D) is an exploded cross-sectional view from the left side showing a connecting portion between the upper and lower liner plates included in the temporary cofferdam structure shown in FIG. 7 and the reinforcing member shown in FIG. 12(A). 8 is an exploded front view showing an example of a waterproof cover included in the temporary coffering structure shown in FIG. 7. FIG. FIG. 8 is a diagram for explaining an example of the work for constructing the temporary cofferdam structure shown in FIG. 7, and is a front view showing a state in which a "hanging scaffold" on the top of a pier and a "float platform" on the pier are installed. Similarly, it is a perspective view showing an assembled state of an assembly intermediate body (first stage) used for constructing a temporary cofferdam structure on a float platform. Similarly, it is a perspective view showing a state in which a waterproof cover is attached to the assembly intermediate body (first stage). Similarly, it is a sectional view taken along the line XVIII-XVIII in FIG. 17. Similarly, it is a perspective view showing a state in which the assembly intermediate body (first stage) is once lifted. Similarly, it is a perspective view showing a state in which the assembly intermediate body (first stage) is lowered. Similarly, it is a perspective view showing a state in which the assembly intermediate body (first stage) is installed on the foundation of a pier. Similarly, it is a sectional view taken along the line XXII-XXII in FIG. 21. Similarly, it is a perspective view showing the assembled state of the assembly intermediate body (second stage) on the float platform. Similarly, it is a perspective view showing a state in which an assembly intermediate body (third stage) is stacked on an assembly intermediate body (second stage) that is connected and fixed to an assembly intermediate body (first stage). Similarly, it is a perspective view showing a state in which the outer surface of the temporary cofferdam structure body is covered with a waterproof cover and supporting rods (strut beams and vertical beams) are provided inside. Similarly, it is a perspective view showing a state in which water is drained from the temporary cofferdam structure to secure a work space in a dry environment. It is a partially enlarged sectional view showing a temporary cofferdam structure according to a second embodiment of the present invention. It is a top view which shows an example of the float platform based on the 3rd Embodiment of this invention. It is a perspective view which shows an example of the float division body which comprises the float platform shown in FIG. 30 is a perspective view showing an example of a curved shape generating spacer included in the float segment shown in FIG. 29. FIG. FIG. 31(A) is a plan view showing one state of the curved shape generating spacer shown in FIG. 30. FIG. FIG. 31(B) is a plan view showing another state of the curved shape generating spacer shown in FIG. 30. FIG. 32 is a plan view showing an example of a float platform using the curved shape generating spacer shown in FIG. 31(B). It is a perspective view which shows an example of the curved shape generation spacer based on the 4th Embodiment of this invention. It is a figure for explaining an example of the construction method of the temporary cofferdam structure concerning the 5th embodiment of the present invention, and puts the float platform in the second state, and temporarily fixes the upper part of the waterproof sheet, and is attached to the foundation of the pier. It is a partial cross-sectional view showing a state in which an assembly intermediate body (second stage) is stacked on the lowermost stage assembly intermediate body (first stage) installed. Similarly, it is a partial sectional view showing a state in which the float platform is in the first state, the assembly intermediate body is assembled in the air, and the joints of the waterproof sheets are joined in stages in the water. It is a figure for explaining an example of the construction method of the temporary cofferdam structure concerning the 6th embodiment of the present invention, and is a figure for explaining an example of the construction method of the temporary cofferdam structure concerning the 6th embodiment of the present invention, and the float platform is set to the first state, and the lowermost stage assembly intermediate body (first stage) is placed in the air. ) is assembled, the lower part of the tarpaulin sheet is attached to it, and the upper part of the tarpaulin sheet is temporarily fixed to the work platform. Similarly, it is a partial cross-sectional view showing a state in which the float platform is in the second state and the lowermost assembly intermediate (first stage) is lowered into water while the upper part of the waterproof sheet is paid out from the work platform. Similarly, this figure shows a state in which the float platform is in the second state and assembly intermediates (second and third stages) are stacked on top of the lowest assembly intermediate (first stage) installed on the foundation of the pier. FIG. It is a figure for explaining an example of the construction method of the temporary cofferdam structure concerning the 7th embodiment of the present invention, and is an assembly intermediate of the lowest stage with the float platform in the second state and the upper part of the waterproof sheet temporarily fixed. FIG. 6 is a partial cross-sectional view showing a state in which an additional assembly intermediate body (second stage) is directly assembled and stacked in the air on top of the body (first stage), and then lowered into water. Similarly, the float platform is set to the second state, and an additional assembly intermediate (third stage) is stacked on top of the additional assembly intermediate (second stage), which is further lowered, and the lowest assembly intermediate (first stage) is stacked on top of the additional assembly intermediate (second stage). Fig. 3 is a partial cross-sectional view showing a state in which the pier) is installed on the foundation of a pier. It is a figure for explaining an example of the construction method of the temporary cofferdam structure concerning the 8th embodiment of the present invention, and is a figure for explaining an example of the construction method of the cofferdam structure concerning the 8th embodiment of the present invention, and puts the float platform in the 2nd state, and is a figure for explaining an example of the construction method of the temporary cofferdam structure concerning the 8th embodiment of the present invention, and is a figure for explaining an example of the construction method of the temporary cofferdam structure concerning the 8th embodiment of the present invention, and the float platform is in the second state, and the lowermost stage assembly intermediate body (1st stage) suspended An additional assembly intermediate body (second stage) is directly assembled and stacked in the air on top of the bottom assembly intermediate body (first stage), and the upper part of the waterproof sheet temporarily fixed to the lowest assembly intermediate body (first stage) is stretched upward. FIG. 6 is a partial cross-sectional view showing a state in which temporary fixing is additionally performed on an additional assembly intermediate body (second stage). Similarly, an additional assembly intermediate (third stage) is stacked on top of the additional assembly intermediate (second stage), lowered further, and the lowest assembly intermediate (first stage) is installed on the foundation of the pier. It is a partial sectional view showing a state in which the waterproof sheet temporarily fixed to the additional assembly intermediate body (second stage) is further extended to the top and joined. It is a figure for explaining an example of the construction method of the temporary cofferdam structure concerning the 9th embodiment of the present invention, and is a figure for explaining an example of the construction method of the temporary cofferdam structure concerning the 9th embodiment of the present invention, and is a figure for explaining an example of the construction method of the temporary cofferdam structure concerning the 9th embodiment of the present invention. FIG. 3 is a partial sectional view showing a state in which a second stage) is lowered into water, an additional assembly intermediate (second stage) is directly assembled and stacked in the air, and further lowered. In the same way, the assembly intermediate body (third stage) is further stacked on top of the additional assembly intermediate body (second stage), and the upper part of the temporarily fixed waterproof sheet is lowered while paying out, and the assembly intermediate body (first stage) is stacked on top of the additional assembly intermediate body (second stage). Fig. 3 is a partial cross-sectional view showing a state in which the pier) is installed on the foundation of a pier.

Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings. In addition, in the following description, directions such as the vertical direction shall be in accordance with the description in the drawings.

<First embodiment>
[Float platform]
In embodiments of the invention, a floating platform is used. This floating platform is used for the construction of temporary cofferdam structures that are constructed when repairing, reinforcing, etc. underwater structures such as bridge piers installed underwater in rivers, etc. An intermediate body for assembling a temporary cofferdam structure, which will be described later, is assembled. As shown in FIGS. 1 to 4, the float platform FP1 is designed to float on the water surface W, and is arranged to surround the pier 10 of the bridge 1, for example. The pier 10 corresponds to an example of an underwater structure in the present invention. The float platform FP1 allows the assembly intermediate body 70 of the temporary cofferdam structure 7 to pass through a reduced state in which the assembly intermediate body 70 of the temporary cofferdam structure 7 can be assembled and held on water (see FIGS. 1 and 2), and the assembly intermediate body 70 of the temporary cofferdam structure 7. In addition, it is configured to be able to change between an expanded state (see FIGS. 3 and 4) that allows it to descend into the water. That is, the reduced state corresponds to the first state in the present invention, and the enlarged state corresponds to the second state in the present invention. As shown in FIGS. 1 to 4, the float platform FP1 includes a work float 2, a passage float 3, and a positioning spacer 4. Although it is desirable for the upper surface of the float platform FP1 to protrude above the water surface W in terms of construction of the temporary cofferdam structure 7, it may be slightly sunk (about 20 cm). Float platform FP1 corresponds to an example of a work platform in the present invention.

Work float 2 is the main component of float platform FP1. In effect, the work float 2 can change between a contracted state and an expanded state while maintaining its integrity. As shown in FIGS. 1 to 4, the work float 2 is equipped with a float division body 5 and a slide mechanism 6. By connecting the float division body 5 with the slide mechanism 6, the work float 2 moves around the pier 10. surrounded.

As shown in FIGS. 1 to 4, the work float 2 (and ultimately the float platform FP1) includes a plurality of (four in this embodiment) float segments 5. As shown in FIGS. 1 to 4 and FIG. 5(A), each float segment 5 has a rectangular shape in plan view, and a rectangular float unit 50 having a rectangular parallelepiped shape and a curved float unit 50 having a curved shape in plan view. It includes a float unit 50A. The rectangular float unit 50 and the curved float unit 50A provide buoyancy to the work float 2. The rectangular float unit 50 has a standard shape as a float unit. The assembly intermediate body 70 includes at least a portion of a curved shape in accordance with the cross-sectional shape of the pier 10. The curved shape of the curved float unit 50A matches the curved shape of the assembly intermediate body 70.

As shown in FIGS. 5(A) and 5(B), the rectangular float unit 50 and the curved float unit 50A are cage-like objects made of L-shaped steel and flat steel, and have a two-layer structure. There is. The upper layer 51 of the two-layer structure is formed to be able to accommodate a slide mechanism 6, which will be described later. The lower layer 52 contains styrofoam 53. The foamed polystyrene 53 is for giving buoyancy to the rectangular float unit 50 and the curved float unit 50A, and is wrapped in ester canvas used for track seats. Note that the number of float division bodies 5 forming the float platform FP1 is not limited to four, but may be two, three, five, six, seven, eight, nine, or more. Furthermore, the term "rectangular" as used herein means quadrilaterals such as rectangles and squares, but includes substantially rectangular shapes. For example, the corners may be rounded or chamfered. Some or all of the sides constituting the rectangle may be curved. The rectangle may be slightly deformed into a trapezoid or parallelogram shape.

As shown in FIG. 5(A), a wooden scaffold board 54 is placed as a work board on the upper surfaces of the rectangular float unit 50 and the curved float unit 50A. The wooden scaffolding board 54 makes the upper surface of the float segment 5 flat, making it easier to work on the float platform FP1. Note that the work plate is not limited to wood, and may be made of metal, FRP, rubber, or resin, and grating is preferable. Examples of the metal include iron, stainless steel, and aluminum. Examples of the resin include vinyl chloride, polypropylene, and polyethylene.

As shown in FIG. 5(A), the float segment 5 includes a straight portion 55 and a curved portion 56. As shown in FIG. The straight portion 55 is manufactured by connecting rectangular float units 50 having a rectangular parallelepiped shape, and its length can be adjusted depending on the number of rectangular float units 50 to be connected. The curved portion 56 is manufactured by combining curved float units 50A having a curved shape in plan view in accordance with the on-site dimensions. As shown in FIG. 5(B), the rectangular float unit 50 has a bolt attachment hole 50b at an end 50a. The float divided body 5 is manufactured by connecting the rectangular float units 50 with each other using bolts 50c and nuts 50d. Curved float unit 50A also has a bolt attachment hole 50b at end 50a. The curved float units 50A and the rectangular float unit 50 and the curved float unit 50A are also connected in the same way. The float segment 5 is not limited to including both the straight part 55 and the curved part 56, and may have only the straight part 55 or only the curved part 56, or may have an L-shape or a U-shape. good.

As shown in FIGS. 6(A) to 6(C), two adjacent float divided bodies 5 are connected by a slide mechanism 6. As shown in FIGS. As shown in FIG. 6(A), the slide mechanism 6 is housed in the upper layer 51 of the two-layer structure of the rectangular float unit 50. As shown in FIGS. 6(B) and 6(C), the slide mechanism 6 is for sliding the adjacent float segments 5 relative to each other, and includes a slide pipe 60 and a slide bar 61. A slide bar 61 is inserted into the slide pipe 60 and integrated in a slidable manner with respect to each other. Two slide mechanisms 6 are provided for each connecting portion 20 between adjacent float segments 5. When assembling the float platform FP1, the slide pipe 60 is fixed to one adjacent float segment 5 using a fixture 62 with bolts 63, and the slide bar 61 is fixed to the other float segment 5 using a fixture 64. It is fixed with bolts 63. Thereby, the two adjacent float division bodies 5 can slide relative to each other. The slide mechanism 6 slides the float segment 5 along the same trajectory every time. Due to this sliding movement, the adjacent float division bodies 5 are separated from each other. By separating, the work float 2 mutually transforms between the contracted state and the enlarged state while maintaining its integrity. Note that the slide mechanism 6 corresponds to an example of a telescopic connection means in the present invention. Moreover, the slide mechanism 6 may be accommodated in the upper layer 51 of the curved float unit 50A.

As shown in FIG. 6(B), when the slide bar 61 slides into the slide pipe 60 in the direction indicated by the arrow N1 and is deeply inserted, the two adjacent float divided bodies 5 are moved relative to each other in the direction indicated by the arrow N1. As a result of the sliding movement in the directions indicated by arrows N1 and N2, the connecting portion 20 is brought into close proximity, and the connecting portion 20 is brought into a closed state. As shown in FIG. 6(C), when the slide bar 61 slides in the direction indicated by arrow N9 and is shallowly inserted into the slide pipe 60, the two float divided bodies 5 are moved relative to each other in the direction indicated by arrow N9. As a result of the sliding movement in the direction indicated by arrow N10, they are separated and the connecting portion 20 is in an open state. In this way, the two adjacent float division bodies 5 can be moved close to each other or separated by relative sliding movement.

As shown in FIGS. 6(B) and 6(C), the slide mechanism 6 includes a stopper mechanism 65. The stopper mechanism 65 is for preventing two adjacent float division bodies 5 from being separated from each other, and includes a contact plate 65a provided at the tip of the slide bar 61 and a pipe end 65b of the slide pipe 60. It is composed of. In the connecting portion 20, when the adjacent float segments 5 relatively slide in the directions shown by arrows N9 and N10 so that the distance between them increases, the abutment plate 65a abuts against the pipe end 65b. The slide movement will stop when it touches the surface.

As shown in FIGS. 1 and 2, the work float 2 (and eventually the float platform FP1) is provided with connecting portions 20 at four locations. Each of these connecting portions 20 is provided with a slide mechanism 6. First, each float segment 5 is appropriately slid relative to the directions shown by arrows N1, N2 and arrows N5, N6 (arrow N1 and arrow N6 are in the same direction, arrow N2 and arrow N5 are in the same direction, N1 and arrow N2 are in opposite directions; arrow N5 and arrow N6 are in opposite directions; the same applies hereafter), and then the arrows N3, N4, and arrows N7, N8 are appropriately slid relative to each other (arrow N3 and arrow N8 is in the same direction, arrow N4 and arrow N7 are in the same direction, arrow N3 and arrow N4 are in opposite directions, arrow N7 and arrow N8 are in opposite directions, and the same applies hereafter). The float segment 5 approaches each other, and the working float 2 is in a closed and contracted state (arrows N1, N2, N5, N6 and arrows N3, N4, N7, N8 are in directions that intersect with each other (including right angles), Same below). Thereby, the float platform FP1 becomes in a state where it is possible to assemble and hold the assembly intermediate body 70 of the temporary coffering structure 7 thereon.

On the other hand, as shown in FIGS. 3 and 4, in the connecting portion 20, each float segment 5 is first relatively slid in the directions shown by arrows N9 and N10 and arrows N13 and N14 (as shown by arrows N9 and N14). the same direction as arrow N14, the same direction as arrow N10 and arrow N13, the opposite direction of arrow N9 and arrow N10, the opposite direction of arrow N13 and arrow N14, and the same below), then arrows N11, N12, and arrow N15. , appropriately relatively slide in the direction indicated by N16 (arrow N11 and arrow N16 are in the same direction, arrow N12 and arrow N15 are in the same direction, arrow N11 and arrow N12 are in the opposite direction, arrow N15 and arrow N16 are (in the opposite direction, the same applies hereinafter), when the interval between the connecting parts 20 is increased, the adjacent float segments 5 are separated from each other, and the working float 2 is in an open and enlarged state (arrows N9, N10, N13, N14 and arrow N11 , N12, N15, and N16 are directions that intersect with each other (including right angles); the same applies hereafter). This creates a gap 21 between the positioning spacer 4 and the work float 2 (each float segment 5). As a result, the work float 2 can pass the assembly intermediate body 70 and be lowered into the water. The sliding movement of the float segment 5 and the positioning of the work float 2 are performed using, for example, a work barge (not shown, the same applies hereinafter).

As shown in FIGS. 1 to 4, the passage float 3 is arranged outside the connecting portion 20 of the work float 2, and is connected to the float division body 5 by a rope (not shown, the same applies hereinafter) or the like. It is used as a passage for workers to move when the work float 2 is expanded. The passage float 3 is also a combination of a plurality of float units 30 that are rectangular in plan view. The float unit 30 is a cage-like object made of L-shaped steel and flat steel, and houses a Styrofoam 31 wrapped in ester canvas inside. As shown in FIG. 4, when the work float 2 is expanded, the outside 2a of the work float 2 is in contact with the inside 3a of the passage float 3.

The positioning spacer 4 is a rubber fender fixed to the wall of the pier 10 with anchor bolts (not shown), and is used to position the work float 2 when assembling the assembly intermediate body 70 of the temporary cofferdam structure 7. , for suppressing vibration. As shown in FIG. 2, the inner side 2a of the work float 2 is in contact with the outer side 4a of the positioning spacer 4 when the float platform FP1 is in a contracted state.

[Temporary cofferdam structure]
FIG. 7, FIG. 8, and FIG. 9 show an example of the temporary cofferdam structure 7 constructed according to this embodiment. The temporary cofferdam structure 7 is installed on the foundation 11 of the pier 10 . The height of the temporary cofferdam structure 7 is set so that its upper part protrudes from the water surface W. That is, the height of the temporary cofferdam structure 7 is determined based on the depth of water such as a river or the sea. Support rods (straight beams 71 and longitudinal beams 72) are appropriately provided inside the temporary cofferdam structure 7. The temporary cofferdam structure 7 includes a temporary cofferdam structure main body 7a and a waterproof cover 7b. The temporary cofferdam structure main body 7a includes a liner plate 73 having a predetermined curvature or a linear shape, and reinforcing members 74, 74A that connect the upper and lower liner plates 73. The reinforcing members 74, 74A also have a predetermined curvature or linear shape. As shown in FIGS. 8 and 9, water-stopping concrete 75 is placed around the bottom of the temporary cofferdam structure 7. Note that the temporary cofferdam structure 7 is not limited to surrounding the entire circumference of the pier 10, but may be one that surrounds a part of the pier 10. The upper surface 75a of the underwater concrete 75 is cast so as to be at the same height or higher than the reinforcing member 74 to which the waterproof sheet 78 is attached.

As shown in FIGS. 7, 8, and 9, the waterproof cover 7b includes a plurality of waterproof sheets 78 arranged along the circumferential direction of the outer surface 7c of the temporary cofferdam structure body 7a, and a plurality of waterproof sheets 78. A joint 78a is formed between the left and right sheet ends 78d of each waterproof sheet 78 when the waterproof sheet 78 is placed on the outer surface 7c, and a waterproof joint 78a is joined to prevent water leakage from the joint 78a. A fastener 79 is provided. The waterproof fastener 79 corresponds to an example of a water leakage prevention joining means in the present invention. The waterproof fastener 79 connects the seams 78a and is waterproof when closed, and separates the seams 78a when opened. The temporary cofferdam structure main body 7a includes a reinforcing member 74 for attaching a waterproof sheet 78. The reinforcing member 74 corresponds to an example of a waterproof sheet attaching portion in the present invention. The reinforcing member 74 is provided at the lower part of the temporary cofferdam structure main body 7a (the first stage assembly intermediate body 70). The waterproof cover 7b is attached to the temporary cofferdam structure main body when the lower part 78b of the waterproof sheet 78 is attached to the reinforcing member 74, the upper part 78e of the waterproof sheet 78 is pulled upward, and the waterproof fastener 79 is pulled upward and closed. It covers the outer surface 7c of 7a.

An example of a liner plate 73 having a predetermined curvature used in constructing the temporary cofferdam structure 7 is shown in FIGS. 10(A) and 10(B). The liner plate 73 is made of, for example, a steel plate. As shown in FIG. 10(A), bolt attachment holes 73b for attaching bolts are provided in the upper, lower, left and right end flanges 73a of the liner plate 73. As shown in FIG. 10(B), the liner plate 73 has a wavy cross section. In addition, in constructing the temporary cofferdam structure 7, not only a curved liner plate but also a linear liner plate 73 is used.

As shown in FIGS. 11(A) and 11(C), each liner plate 73 is connected in the circumferential direction by connecting the left and right end flanges 73a with bolts without intervening rubber water-stop packing. This is done by tightening the nuts 73c and 73d. Further, to connect the liner plates 73 in the vertical direction, as shown in FIGS. 11(B) and 11(C), the upper and lower end flanges 73a of the liner plates 73 are connected by rubber water-stop packing. This is done by fastening bolts 73c and nuts 73d without any intervention. Note that, as shown in FIG. 11C, the circumferential seams between the liner plates 73 do not necessarily have to match in the vertical direction. Moreover, a rubber water-stop packing may be interposed between each liner plate 73 just in case. An example of the rubber water stop packing is a band-shaped water stop packing.

FIG. 12(A) shows a reinforcing member 74 having a predetermined curvature used in constructing the temporary cofferdam structure 7. The reinforcing member 74 is made of H-beam steel, and has bolt mounting holes 74c for mounting bolts in its web 74b. Further, the flange 74d of the reinforcing member 74 is provided with a bolt attachment hole 74e for attaching a splint plate 77, which will be described later. Further, the flange 74d is provided with bolt attachment holes 74f for attaching a waterproof sheet 78, which will be described later. In addition, in constructing the temporary cofferdam structure 7, not only the reinforcing member 74 having a curved shape but also a linear shape is used.

FIG. 12(B) shows a reinforcing member 74A having a predetermined curvature used in constructing the temporary cofferdam structure 7. The reinforcing member 74A is different from the above-mentioned reinforcing member 74 in that it does not have a bolt attachment hole 74f for attaching a later-described waterproof sheet 78 to the flange 74d. In this embodiment, this reinforcing member 74A is used in locations where the waterproof sheet 78 is not attached. Of course, reinforcing members 74 can also be used at these locations.

As shown in FIG. 13(A), the reinforcing member 74 is attached to the first and second liner plates 73 from the bottom of three stacked liner plates 73 stacked in the vertical direction (assembly intermediate body 70 to be described later). It is arranged between the end flanges 73a, and is fastened to the liner plate 73 with bolts 73c and nuts 73d without intervening rubber water-stop packing. A splint plate 77 shown in FIG. 13(B) is attached to the circumferential seam of the reinforcing member 74. The splint plate 77 has a bolt attachment hole 77a for attaching a bolt 73c, and the bolt attachment hole 77a is aligned with the bolt attachment hole 74e as shown in FIG. 13(C). As shown in (D), bolts 73c and nuts 73d are fastened to the reinforcing member 74 without intervening rubber water-stop packing. As a precaution, a rubber water-stop packing may be interposed between the abutting web end surfaces 74g of each reinforcing member 74 or between the web 74b of the reinforcing member 74 and the end flange 73a of the liner plate 73. An example of a rubber water stop packing is a band-shaped water stop packing. On the other hand, the reinforcing member 74A is arranged between the upper and lower end flanges 73a of the liner plates 73 for every three stacked liner plates 73 stacked in the vertical direction (assembly intermediate bodies 70, 70A to be described later), The liner plate 73 is fastened to the bolts 73c and nuts 73d without intervening rubber water-stop packing. The reinforcing member 74A can also be attached to the temporary cofferdam structure main body 7a in the same manner as the reinforcing member 74.

As shown in FIGS. 7, 8, and 9, in the construction of the temporary cofferdam structure 7 of this embodiment, the assembly intermediate bodies 70, 70A are annular bodies in which liner plates 73 are connected in the circumferential direction of the pier 10. It is made of 3 layers. A reinforcing member 74A is arranged between the upper and lower assembly intermediate bodies 70 and the assembly intermediate body 70A. The assembly intermediate body 70 forms the first stage of the temporary cofferdam structure main body 7a. The assembly intermediate body 70A forms the second and third stages of the temporary cofferdam structure main body 7a. The height of the assembly intermediate bodies 70, 70A (that is, the number of stacked annular bodies) is appropriately determined in consideration of smooth lowering work described below and workability on the float platform FP1. For example, if the height of the liner plate 73 (height in the vertical direction in FIG. 10(A)) is 500 mm, three layers (1.5 m) are used based on ease of operation for the operator.

Note that the number of stacked liner plates 73 in the assembly intermediate bodies 70, 70A is not limited to three, but may be one, two, four, five, six, or more. Further, in the first-stage assembly intermediate body 70, a reinforcing member 74 is arranged between the liner plates 73 of the first and second layers from the bottom. This is for attaching a waterproof cover 7b, which will be described later. Of course, the reinforcing member 74 can also be used between the assembly intermediate bodies 70 and 70A instead of the reinforcing member 74A. Further, the temporary cofferdam structure 7 is a structure in which assembly intermediate bodies 70, 70A are stacked in an appropriate number of stages depending on the water depth (three stages in this embodiment). The temporary cofferdam structure 7 may be constructed with one stage of assembly intermediates 70, or may be constructed with two, four, five, six, or more stages of assembly intermediates 70, 70A. .

As described above, the waterproof cover 7b includes a waterproof sheet 78 and a waterproof fastener 79. The waterproof sheet 78 is for preventing water from outside the temporary coffering structure 7 from leaking into the inside. The waterproof sheet 78 is formed, for example, into a rectangular shape using, for example, a track sheet made of ester canvas. A resin coating layer is formed on the outer surface of the waterproof sheet 78 by resin coating for protection. For painting, for example, a paint whose main component is polyurethane resin, polyurea resin, polyolefin resin, etc. is used. An example of a paint containing polyurea resin as a main component is LINE-X (registered trademark).

As shown in FIG. 14, bolt attachment holes 78c for attaching to the reinforcing member 74 of the assembly intermediate body 70 are formed in the lower part 78b of the waterproof sheet 78. A plurality of waterproof sheets 78 are arranged side by side in the circumferential direction to cover the outer surface 7c of the temporary cofferdam structure main body 7a. By arranging them side by side in the circumferential direction, a joint 78a is formed between the sheet ends 78d of the adjacent waterproof sheets 78 in the left and right direction. The seams 78a are those where the sheet ends 78d of the waterproof sheet 78 are butted against each other, those where the sheet ends 78d are overlapped, and those where the sheet ends 78d are close to each other and a gap is created. including.

Note that the waterproof cover 7b may be formed of a single waterproof sheet 78, and in this case, the seam 78a is formed between the left and right sheet ends 78d of the single waterproof sheet 78. In this case as well, the seams 78a are those where the sheet ends 78d of the waterproof sheet 78 are butted against each other, those where the sheet ends 78d are overlapped, and the seams 78a where the sheet ends 78d are close to each other and a gap is created. Including those in a condition.

As shown in FIG. 14, the waterproof fastener 79 is arranged at the joint 78a of the plurality of waterproof sheets 78, and prevents water from outside the temporary coffering structure 7 from leaking into the inside. It is for joining. The number of locations where the waterproof fasteners 79 are attached is determined by the size of the temporary cofferdam structure main body 7a. The waterproof fastener 79 includes a pair of elements 79b and 79c attached to a tape 79a that engage with each other, and a slider that is arranged between the pair of elements 79b and 79c and moves up and down to engage and disengage the pair of elements 79b and 79c. 79d. The slider 79d is attached to one of the pair of elements 79b and 79c, for example, the element 79c, in the waterproof sheet 78 before joining.

The tape 79a is, for example, a polyester base fabric whose front and back surfaces are coated with vinyl chloride (PVC), chloroprene synthetic rubber (CR), or polyurethane (PU). The elements 79b and 79c are made of nickel silver. The slider 79d is made of aluminum bronze. The pair of elements 79b and 79c are attached to the left and right sheet ends 78d of adjacent waterproof sheets 78 via tapes 79a. By operating the slider 79d, the inner element engages and the waterproof zipper 79 is closed. The pair of elements 79b and 79c are not stopped at the top or bottom, so that the waterproof sheet 78 can be handled separately from each other. Note that when the joint 78a is such that the sheet end portions 78d overlap each other, the waterproof fastener 79 is attached to a predetermined location of the overlapped portion. When the waterproof fastener 79 is closed and the pair of elements 79b and 79c are engaged, the ends of the left and right tapes 79a are compressed and sealed.

When the waterproof sheet 78 is attached to the temporary cofferdam structure main body 7a, it is connected by a slider 79d at the lower part 78b. In this state, the upper parts 78e of the adjacent waterproof sheets 78 are not connected, so the upper parts 78e can be rolled up into a roll shape or folded into a bellows shape to make it more compact. Of course, the pair of elements 79b and 79c may be lowered in advance before being attached to the temporary coffering structure main body 7a, and a plurality of waterproof sheets 78 may be connected from the beginning. Further, as described above, the waterproof cover 7b may be formed by wrapping one waterproof sheet 78 around the outer surface of the temporary cofferdam structure main body 7a, and in that case, the left and right sheet ends 78d of the waterproof sheet 78 A waterproof fastener 79 is attached to the parts, and they are connected in a ring. Also in this case, if the joint 78a is such that the sheet end portions 78d overlap, the waterproof fastener 79 is attached to a predetermined location of the overlapped portion. Specifically, for example, AQUASEAL (registered trademark) manufactured by YKK Corporation is used as the waterproof fastener 79.

The elements 79b and 79c of the waterproof fastener 79 may include an outer element and an inner element provided inside the outer element. In this case, the left and right inner elements are engaged with each other by operating the slider 79d, and the waterproof fastener 79 is closed. At this time, the elastic tape 79a is compressed between the left and right outer elements, creating a more airtight state. An example of such a waterproof fastener 79 is PROSEAL (registered trademark) manufactured by YKK Corporation.

The waterproof sheet 78 may be provided with a floating member on the upper portion 78e. This is to allow the waterproof sheet 78 to float or float in the water after being removed from the temporary fixing portion 70b. It is preferable that the floating member has a rod-like shape, for example. Alternatively, a structure in which small floating members are connected in the form of beads may be used.

[Construction method of temporary cofferdam structure]
Next, a method of constructing the temporary cofferdam structure 7 on the bridge 1 using the float platform FP1 of this embodiment will be described. The construction method of the temporary cofferdam structure 7 includes a construction step of constructing the temporary cofferdam structure body 7a around the pier 10, and a covering step of covering the outer surface 7c of the temporary cofferdam structure body 7a with a waterproof cover 7b. have.

In the present embodiment, the construction process includes a float platform installation process of installing the float platform FP1, an assembly process of assembling the assembly intermediates 70 and 70A, a lowering process of lowering the assembly intermediates 70 and 70A into the water, and a final step. and an installation step of installing the lower assembly intermediate body 70 on the foundation 11 of the pier 10. It also includes a stacking step of stacking the assembly intermediate bodies 70, 70A until the temporary cofferdam structure main body 7a reaches a desired height by repeating the assembly step and the lowering step as necessary. ing. Note that the foundation 11 of the pier 10 includes those on which assembly intermediate bodies 70, 70A, etc. are already installed in advance.

Further, in the covering step, when the assembly intermediate bodies 70, 70A are assembly intermediate bodies 70, 70A disposed at the lower part of the temporary cofferdam structure main body 7a, A waterproof sheet attachment part installation step in which a reinforcing member 74 as a waterproof sheet attachment part is provided at a predetermined location of the assembly intermediate body 70, 70A , and a joint 78a is formed between the sheet end 78d of at least one waterproof sheet 78. a waterproof sheet attaching step of arranging at least one waterproof sheet 78 along the circumferential direction of the temporary cofferdam structure main body 7a, and attaching a lower part 78b of the at least one waterproof sheet 78 to the reinforcing member 74; a temporary fixing step of temporarily fixing the upper part 78e of the waterproof sheet 78 to the temporary fixing part 70b provided on the assembly intermediate body 70 disposed at the lower part of the temporary cofferdam structure main body 7a with the waterproof fastener 79 opened. ing. In addition, the said waterproof sheet attachment part installation process, the said waterproof sheet attachment process, and the said temporary fixing process are performed in parallel with the said assembly process in the air.

The construction method for the temporary cofferdam structure 7 will be described in more detail below with reference to FIGS. 15 to 26.

As shown in FIG. 15, in constructing the temporary cofferdam structure 7, a hanging scaffold SS is provided on the lower surface of the bridge girder 13 installed on the pier upper part 12, if necessary. This suspended scaffold SS secures a movement space for a worker (not shown, the same applies hereinafter) by fixing the periphery of the scaffold board to the lower surface of the bridge girder 13 with a hanging rod.

As shown in FIG. 16, on this suspended scaffold SS (not shown in FIG. 16), a total of two shoring structures 8 are installed, one on each side of the upper surface of the pier upper part 12. The shoring 8 is divided into three parts in the length direction. A clamping piece 80 is provided on each of the split supports 8a and 8b at both ends. The support 8 is fixed to the pier upper part 12 by applying the clamping piece 80 to the side surface of the pier upper part 12 and connecting the divided supports 8a, 8b, and 8c.

Hanging fittings 81 are provided at both ends of the shoring 8, and wires 82 are provided on the hanging fittings 81. An electric chain block (electric hoist) 83 is provided on the wire 82, and a pair of hanging hooks 84 are provided on the hanging cord (wire) of the electric chain block 83. However, the number of hanging hooks 84 is arbitrarily selected so that the temporary coffering structure 7 or its assembly intermediate bodies 70, 70A can be hung stably and safely. In addition, when the suspended scaffolding SS is not constructed, the shoring 8 etc. may be hoisted up with a crane, and the worker may also be moved up and down to the working position using the crane.

Next, as shown in FIG. 16, the worker installs the floating platform FP1 for work, and then assembles the assembly intermediate body 70 (first stage) of the temporary cofferdam structure 7. A working float platform FP1 is installed on the water around the pier 10 using a float division body 5, a slide mechanism 6, a passage float 3, and a positioning spacer 4. This float platform FP1 installation process corresponds to an example of the work platform installation process in the present invention. These members and necessary equipment will be transported to the construction location by an equipment barge (not shown). The float platform FP1 may be appropriately set to have a ring shape, an elliptical ring shape, an oval ring shape, or the like, depending on the annular shape of the temporary cofferdam structure 7. In this embodiment, since the cross section of the pier 10 is an oval annular shape, the temporary cofferdam structure 7 is also an oval annular shape, and accordingly, the float platform FP1 is also an oval annular shape. Before transporting the float division body 5 on an equipment barge, as shown in FIGS. 5(A) and 5(B), a rectangular float unit 50 and a curved float unit 50A of appropriate shapes are combined, and bolts 50c are assembled. , are assembled in advance using nuts 50d.

As shown in FIGS. 1, 2, and 16, in installing the float platform FP1, the positioning spacer 4 is fixed to the wall of the pier 10 with anchor bolts (not shown), and the four float segments 5 are attached to the pier 10. The working float 2 is assembled by arranging the slide mechanism 6 around the float and further fixing the slide mechanism 6 to the adjacent float segments 5 to form the connecting portion 20. Thereby, the work float 2 can relatively slide and move at the four connecting portions 20 without the float segments 5 being separated, and can take a contracted state and an enlarged state. This work float 2 serves as an actual work place for assembling the assembly intermediate bodies 70 and 70A of the temporary cofferdam structure 7. The installation of the float platform FP1 is completed by connecting the passage float 3 to the vicinity of the connecting portion 20 of the float segment 5 with a rope. The length of this rope is adjusted so that when the connecting portion 20 is opened, the passage float 3 approaches the work float 2 to the extent that a worker can get on it.

Next, an assembly step is performed to assemble the assembly intermediate body 70 (first stage) of the temporary cofferdam structure 7 on the float platform FP1 that has been completely installed. As shown in FIGS. 1, 2, and 16, an operator first moves each slide segment 5 using a work barge, for example, to move the float segment 5 in the directions indicated by arrows N1, N2 and arrows N5, N6. The work float 2 (and thus the float platform FP1) is brought into a contracted state by appropriately sliding the work float 2 (and eventually the float platform FP1) in the directions shown by the arrows N3 and N4 and the arrows N7 and N8. In the contracted state, the float platform FP1 can assemble and hold the assembly intermediate 70 in air.

As shown in FIGS. 11A and 16, the worker connects the liner plates 73 in the circumferential direction of the pier 10 from the inside using bolts 73c and nuts 73d, and assembles the first layer. As shown in FIGS. 13(A) to 13(D) and FIG. 16, a reinforcing member 74 is placed on the first layer and connected in the circumferential direction using bolts 73c and nuts 73d. At this time, the splint plate 77 is fixed to the circumferential joint with a dowel bolt 73c and a nut 73d. Thereafter, as shown in FIGS. 11(A) to 11(C) and FIG. 16, the assembly work is repeated to stack three layers of liner plates 73 to a height of 1.5 m. A reinforcing member 74A is placed on the top and connected in the circumferential direction in the same manner as the reinforcing member 74. The reinforcing member 74 corresponds to an example of the tarpaulin attaching part in the present invention, and the process of installing the tarpaulin attaching part is performed in air in parallel with the assembling process of the assembly intermediate body 70. Note that the reinforcing member 74 is not limited to being installed on the first-stage assembly intermediate body 70, but can be installed on the second-stage and subsequent assembly intermediate bodies 70A as long as it is placed at the lower part of the temporary cofferdam structure main body 7a. May be installed.

Next, as shown in FIGS. 17 and 18, the worker installs the waterproof cover 7b in the air around the assembly intermediate body 70 (first stage) so that the entire circumference becomes one piece. First, the worker fastens the lower part 78b of each waterproof sheet 78 to the reinforcing member 74 with bolts 73c and nuts 73d, winds up the upper part 78e of each waterproof sheet 78 into a roll, and attaches the wound body 78f to a fixed rope. 78g, it is fixed to the temporary fixing part 70b provided on the assembly intermediate body 70. Thereafter, the operator attaches the slider 79d to the pair of elements 79b, 79c between each waterproof sheet 78 and integrates them. In addition, the upper part 78e of each waterproof sheet 78 may be folded into a bellows shape. In this way, the waterproof sheet attachment process and temporary fixing process are also performed in air in parallel with the assembly process of the assembly intermediate body 70.

Next, the process moves to a lowering step in which the assembled intermediate body 70 is lowered into water. As shown in FIG. 19, the worker hooks the hook 84 of the electric chain hoist 83 onto the assembly intermediate body 70 (first stage), operates the switch, and moves from the float platform FP1 in the direction indicated by the arrow N17 (upward, (Same below). Thereafter, the worker uses the work barge to first relatively slide the adjacent float segments 5 in the directions indicated by arrows N9, N10 and arrows N13, N14, and then moves them in the directions indicated by arrows N11, N12 and arrow N15. , N16, the working float 2 (and eventually the float platform FP1) is brought into an enlarged state while maintaining its integrity. Then, the assembly intermediate body 70 (first stage) passes between the positioning spacer 4 and the work float 2, creating a gap 21 that can be lowered into the water. In this enlarged state, the connecting portions 20 of the adjacent float segments 5 are spread out, which is dangerous, so the passage float 3 is used when the worker moves on the float platform FP1.

Next, as shown in FIG. 20, the worker operates the switch on the electric chain hoist 83 and points the assembly intermediate body 70 (first stage) toward the foundation 11 of the pier 10 by arrow N18 (downward, the same applies hereafter). ) in the direction shown by the gap 21 and descend into the water. At that time, the worker follows instructions regarding the installation location via an underwater telephone from a diver (not shown, the same applies hereinafter).

Next, as shown in FIGS. 21 and 22, an installation process is performed in which the assembly intermediate body 70 (first stage) is installed at an appropriate position on the foundation 11 of the pier 10 . After the diver removes the hook 84 of the electric chain hoist 83 from the assembled intermediate body 70 (first stage), the worker raises the hook 84 to a predetermined position in the direction indicated by arrow N17. The diver fixes the assembly intermediate body 70 (first stage) to the foundation 11 of the pier 10 with the anchor bolts 73e, and attaches the liner plate 73 ( A concrete mixer truck (not shown) parked on the bridge girder 13 is used to feed underwater concrete for water-stopping purposes between the formwork and the assembly intermediate body 70. Set up The upper surface 75a of the underwater concrete 75 is located higher than the lower end of the waterproof sheet 78. This prevents water from entering through the gap formed between the foundation 11 of the pier 10 and the bottom of the temporary cofferdam structure 7. Note that the underwater concrete 75 may be placed after all of the assembly intermediate bodies 70 and 70A, which will be described later, are laminated.

Next, a stacking process is performed in which the assembly intermediate bodies 70, 70A are stacked on top of each other by repeating the assembly process and the lowering process as necessary until the temporary cofferdam structure main body 7a reaches a desired height. As shown in FIG. 23, after installing the assembly intermediate body 70 (first stage), the worker slides and moves each float segment 5 by pushing using a work barge in the same manner as described above. The work float 2 is brought into a reduced state, and the assembly work of the second-stage assembly intermediate body 70A is performed thereon. Thereafter, the worker temporarily lifts the assembly intermediate body 70A (second stage) in the direction shown by the arrow 17, and returns the work float 2 to the enlarged state. The diver instructs and guides the worker using the underwater telephone, places the assembly intermediate body 70A (second stage) on top of the assembly intermediate body 70 (first stage), and places the assembly intermediate body 70A (first stage) on top of the assembly intermediate body 70 (first stage). As shown in (D), connection work is performed using bolts 73c and nuts 73d.

Next, as shown in FIG. 24, the worker similarly reduces the work float 2, assembles the third stage assembly intermediate body 70A, and once lifts it in the direction shown by arrow N17, and enlarges the work float 2. The diver then lowers the assembly intermediate body 70A (third stage) onto the assembly intermediate body 70A (second stage) in the direction shown by arrow N18, and performs the connection work. In this embodiment, the upper surface of the assembly intermediate body 70A (third stage) is located above the water surface W and above the float platform FP1. The construction of the temporary cofferdam structure 7 can be completed here, or if necessary, the liner plate 73 may be further laminated directly on the upper surface of the assembly intermediate body 70A (third stage). The assembly intermediate bodies 70, 70A may be connected and fixed each time the assembly intermediate bodies 70, 70A are stacked, as in the present embodiment, or after the assembly intermediate bodies 70, 70A are stacked. You may do so.

Next, as shown in FIG. 25, once the installation of the temporary coffering structure 7 on the foundation 11 of the pier 10 is completed, the diver pulls each waterproof sheet up into the air as shown by arrow N22, The waterproof cover 7b is completed by fixing it to the upper part of the temporary coffering structure main body 7a, pulling up the slider 79d to the air part, and closing the waterproof fastener 79 (pulling up and closing the waterproof fastener 79 to the air part). Also. The diver appropriately installs supporting rods (straight beams 71 and longitudinal beams 72) inside the temporary cofferdam structure 7. Note that each waterproof sheet may be temporarily fixed to the upper part of the temporary coffering structure main body 7a.

Next, as shown in FIG. 26, the worker removes the float platform FP1 from around the pier 10. After that, the worker takes the tip 85a of the hose 85 out from above the temporary cofferdam structure 7, drains the water inside the temporary cofferdam structure 7 using a submersible drainage pump (not shown), and performs work in a dry environment. Reserve your space. Of course, the removal work of the float platform FP1 may be performed after the water draining work.

Inside the temporary cofferdam structure 7, workers carry out renovations such as repairing and reinforcing the bridge piers. After the repair is completed, the temporary cofferdam structure 7 will be removed.

According to this embodiment, the temporary cofferdam structure 7 includes a waterproof cover 7b on the outer surface 7c of the temporary cofferdam structure main body 7a. The waterproof cover 7b can cover the outer surface 7c of the temporary cofferdam structure main body 7a with a relatively simple operation, and prevents water from leaking into the interior of the temporary cofferdam structure 7. Therefore, when connecting the liner plates 73 in the assembly work of the temporary cofferdam structure body 7a on and under water, it is not necessary to carefully and strongly tighten the bolts 73c and nuts 73d with the interposition of water-stop packing. good. Thereby, it is possible to improve the efficiency of the construction work of the temporary cofferdam structure 7, thereby shortening the construction period and reducing costs.

In addition, the temporary coffering structure 7 can cover the outer surface 7c of the temporary coffering structure main body 7a with the waterproof cover 7b, so there is no need to interpose water-stop packing to strongly tighten the bolts 73c and nuts 73d. Deformation of the plate 73 can be prevented. This allows the liner plate 73 to be reused. From this point as well, it is possible to reduce the cost of constructing the temporary cofferdam structure 7.

In addition, when performing connection work underwater, divers must work in an unstable position, so when assembling the water-stop gasket, it is easy to damage the water-stop gasket, causing seal leaks. was there. According to this embodiment, water leakage caused by such damage to the water stop packing is prevented by a simple operation of covering the temporary cofferdam structure main body 7a with the waterproof cover 7b instead of the water stop packing. be able to.

Further, the waterproof cover 7b is provided with a waterproof fastener 79 at the joint 78a, and simply by closing the waterproof fastener 79, water can be prevented from leaking into the interior of the temporary cofferdam structure main body 7a. Therefore, when connecting the liner plates 73, there is no need to interpose water-stop packing and carefully and strongly tighten the bolts 73c and nuts 73d. Thereby, it is possible to improve the efficiency of the construction work of the temporary cofferdam structure 7, thereby shortening the construction period and reducing costs.

Further, the temporary cofferdam structure main body 7a has a reinforcing member 74 for attaching a waterproof sheet 78 at the lower part (assembly intermediate body 70) of the temporary cofferdam structure main body 7a, and the lower part 78b of the waterproof sheet 78 has a reinforcing member 74. 74. When covering the outer surface 7c of the temporary coffering structure main body 7a with the waterproof cover 7b, the upper part 78e of each waterproof sheet 78 is pulled upward, and the waterproof fastener 79 is pulled upward and closed. Ru. In this way, the temporary cofferdam structure main body 7a can be covered with the waterproof cover 7b by a simple operation. Thereby, it is possible to improve the efficiency of the construction work of the temporary cofferdam structure 7, thereby shortening the construction period and reducing costs.

Further, in the step of covering the waterproof cover 7b, the upper part 78e of the waterproof sheet 78 is temporarily fixed, so that the waterproof cover 7b can be quickly covered on the temporary coffering structure 7a. Therefore, the burden on the worker can be reduced and the construction work can be carried out efficiently. Thereby, it is possible to shorten the construction period and reduce costs for the construction work of the temporary cofferdam structure 7.

In addition, the upper part 78e of the waterproof sheet 78 is attached to the temporary fixing part 70b as a rolled body 78f wound up in a roll shape or as a folded body folded in a bellows shape when the waterproof fastener 79 is pulled down and opened. Fixed temporarily. In this way, when covering the outer surface 7c of the temporary cofferdam structure main body 7a with the waterproof cover 7b, the waterproof sheet 78 is compactly attached to the temporary cofferdam structure main body 7a. Thereby, the temporary coffering structure main body 7a can be easily covered with the waterproof cover 7b. Further, the work of lowering the assembly intermediate body 70 can be easily performed. Therefore, the work of covering the outer surface 7c of the temporary coffering structure main body 7a with the waterproof cover 7b can be efficiently carried out. Thereby, it is possible to shorten the construction period and reduce costs for the construction work of the temporary cofferdam structure 7.

Further, a resin coating layer is formed on the outer surface of the waterproof sheet 78. Therefore, the waterproof sheet 78 has improved waterproof properties. Thereby, water leakage prevention can be improved. Furthermore, the resin coating layer improves the impact resistance of the waterproof sheet 78. This allows the waterproof sheet 78 to last a long time, making it easy to reuse and reducing costs.

In addition, in constructing the temporary cofferdam structure 7, the assembly of the assembly intermediate bodies 70, 70A is performed on the float platform FP1, so the proportion of above-water work can be increased, while the proportion of underwater work by divers can be reduced. can. Therefore, the number of days required for underwater work can be reduced. In addition, while it is possible to increase the proportion of above-water work in ascertaining the assembly state, locating members, checking strain, etc., it is possible to reduce the proportion of underwater work by divers. In this respect as well, the number of days required for underwater work can be reduced. In addition, since the amount of work required to unload cargo from the surface to the water can be reduced, this is also a factor in reducing the number of days required for underwater work by divers. On the other hand, due to air supply issues, the number of divers who can work underwater is limited. On the other hand, work on water is less subject to such restrictions. Therefore, by reducing underwater work, the total number of work days can be reduced. Thereby, it is possible to shorten the construction period and reduce costs in constructing the temporary cofferdam structure 7. Additionally, underwater work has a high risk of accidents. According to this embodiment, it is possible to reduce the number of working days for underwater work, thereby reducing the dangers caused by underwater work.

Furthermore, the float platform FP1 can be easily assembled on water using members that can float on water. Furthermore, the float platform FP1 can easily and reliably convert between a contracted state in which the assembly intermediate bodies 70 and 70A can be assembled and an expanded state in which it can be lowered into water while maintaining its integrity by the slide mechanism 6. Therefore, the work of assembling the assembly intermediate bodies 70, 70A and the work of lowering them into the water can be carried out smoothly, and the work on the water and the work in the water can be appropriately distributed. Therefore, it is possible to efficiently construct a temporary cofferdam structure underwater. With these, the number of working days can be shortened. Therefore, it is possible to shorten the construction period and reduce costs for constructing the temporary cofferdam structure 7.

Furthermore, the float platform FP1 includes a positioning spacer 4. The positioning spacer 4 can suppress the rocking of the float platform FP1 when assembling the assembly intermediate bodies 70, 70A. Thereby, the assembly intermediate bodies 70, 70A of the temporary closing structure 7 can be assembled accurately, and the occurrence of problems such as seal leakage can be reduced.

Furthermore, the float platform FP1 includes a passage float 3. When the float platform FP1 is in the expanded state, the connecting portions 20 between the adjacent float segments 5 are in an open state. At that time, the worker transfers from the work float 2 to the passage float 3 and moves. This makes it possible to improve worker safety.

Furthermore, since the step of covering the waterproof cover 7b can be carried out in the air, it is possible to reduce the labor of the diving operator and improve work efficiency.

In addition, when a floating member is provided on the upper part 78e of the waterproof sheet 78, after removing the waterproof sheet 78 from the temporary fixing part 70b, the joints 78a of the waterproof sheets 78 can be joined while floating or floating in water. Therefore, it is possible to reduce the labor of diving workers and improve work efficiency.

<Second embodiment>
With reference to FIG. 27, a temporary closing structure 7A according to a second embodiment of the present invention will be described. In the temporary cofferdam structure 7A, components having the same or similar functions as those of the temporary cofferdam structure 7 according to the first embodiment are given the same reference numerals as those of the temporary cofferdam structure 7. Regarding these, detailed explanation will be omitted. As shown in FIG. 27, the temporary coffering structure 7A has no bolt mounting holes 78c formed in the lower part 78b of the waterproof sheet 78A, and is equipped with a clamp 9, a water stop packing 78k, and a holding plate 78l. This is different from the first embodiment. The second embodiment is also different from the first embodiment in that it includes an FRP board 78i and a coconut fiber mat 78j.

The clamp 9 is for attaching the waterproof cover 7b to the temporary cofferdam structure main body 7a. This installation work is done in air. The clamp 9 includes a main body portion 90, a bolt portion 91, and a handle 92. The main body portion 90 includes a jaw portion 90a. The bolt portion 91 includes a tip portion 91a. The object is sandwiched between the jaw portion 90a and the tip portion 91a. By rotating the handle 92, the object is tightened.

When attaching the waterproof cover 7b to the temporary cofferdam structure main body 7a, first, the waterproof packing 78k is attached to the surface of the outer flange 74d of the reinforcing member 74. Next, the lower part 78b of the waterproof sheet rolled up in advance is placed on the surface of the waterproof packing 78k. Further, on the surface of the lower portion 78b of the waterproof sheet, pressing plates 78l are arranged at predetermined intervals (for example, every approximately 20 cm). The holding plate 78l is, for example, a square with a side of 50 mm. Of course, it may also be rectangular, circular, oval, oval, or the like. A belt-like shape may be adopted as the shape of the pressing plate 78l. When the pressing plate 78l is strip-shaped, it presses the lower part 78b of the waterproof sheet along the circumferential direction. In this case, a space may or may not be provided between the pressing plates 78l. The flange 74 d of the reinforcing member 74 , the water-stop packing 78 k , the waterproof sheet 78 , and the presser plate 78 l are sandwiched between the jaw portion 90 a of the main body 90 of the clamp 9 and the tip portion 91 a of the bolt 91 . Fixed by rotation. The fixing is performed at a plurality of locations at the predetermined intervals around the temporary cofferdam structure main body 7a. Specifically, as the clamp 9, for example, a Bulman (registered trademark), a Liquiman (registered trademark), a Shaco vise, or the like is used. Further, as the holding plate 78l, for example, flat steel or the like is used. The water stop packing 78k and the pressing plate 78l of this embodiment are also applicable to the first embodiment.

The flanges 74d of the reinforcing members 74, 74A protrude from the outside of the liner plate 73. A space 78h (about 24 mm, for example) is generated between the waterproof sheet 78A attached to the outside of the flange 74d of the reinforcing members 74, 74A and the outside of the liner plate 73. To fill this space 78h, a coconut fiber mat 78j (about 30 mm thick) is filled between the upper and lower reinforcing members 74, 74A. The coconut fiber mat 78j corresponds to an example of a filler according to the present invention. Furthermore, in order to prevent the coconut fiber mat 78j from expanding into the uneven portion of the liner plate 73, strip-shaped FRP plates 78i are inserted at equal intervals between the liner plate 73 and the coconut fiber mat 78j. The coconut fiber mat 78j of this embodiment is also applicable to the first embodiment.

According to this embodiment, the same effects as the first embodiment are achieved.

Moreover, in this embodiment, the clamp 9 is used to attach the waterproof cover 7b to the temporary cofferdam structure main body 7a. The installation work using the clamp 9 has excellent workability. Thereby, it is possible to improve the efficiency and reliability of the work in constructing the temporary cofferdam structure 7. Furthermore, it is possible to shorten the construction period and reduce costs.

Furthermore, in this embodiment, a coconut fiber mat 78j is filled in the gap between the temporary cofferdam structure main body 7a and the waterproof cover 7b. Therefore, stretching of the waterproof sheet 78 due to water pressure can be alleviated. Thereby, the waterproof sheet 78A can be easily reused, and costs can be reduced.

<Third embodiment>
Float platforms FP2 and FP3 according to the third embodiment of the present invention will be described with reference to FIGS. 28 to 32. In the float platforms FP2 and FP3, components having the same or similar functions as the components of the float platform FP1 according to the first embodiment are given the same reference numerals as those of the float platform FP1. Regarding these, detailed explanation will be omitted.

First, as shown in FIG. 28, the float platform FP2 is adapted to fit the pier 10A and is configured to be able to assemble the assembly intermediate body 70B, and is equipped with a working float 2F including the float segment 5A. This is different from the first to second embodiments. The assembly intermediate body 70B is different from the assembly intermediate body 70 in the shape that it exhibits in plan view.

As shown in FIGS. 28 and 29, the working float 2A is manufactured by connecting four divided float bodies 5A. The float segment 5A includes a straight portion 55 and a curved portion 56A. The straight portion 55 is manufactured by connecting rectangular float units 50 having a rectangular parallelepiped shape, and its length can be adjusted depending on the number of rectangular float units 50 to be connected. The rectangular float unit 50 has a square shape in plan view. The curved portion 56A is manufactured by combining two rectangular parallelepiped-shaped rectangular float units 50 and two triangular prism-shaped curved shape generating spacers 50B. The curved shape generating spacer 50B has a triangular shape in plan view. One corner 57a of the curved shape generating spacer 50B is arranged inside the work float 2A, and the other two corners 57b and 57c are arranged outside. The angles of these corner portions 57a, 57b, and 57c are configured to be changeable. The curved shape portion 56A is formed to match the outer shape of the pier 10A by connecting the curved shape generating spacer 50A with the angles of the corners 57a, 57b, and 57c adjusted to the adjacent rectangular float unit 50. The rectangular float unit 50 is not limited to a square shape in plan view, but may have another rectangular shape such as a rectangular shape.

The number of curved shape generating spacers 50B used to manufacture the float segment 5A is not limited to two, but may be one, three, five, six, seven, etc. according to the outer shape of the pier 10A. The number may be eight, nine, or more. It is also possible to connect a plurality of curved shape generating spacers 50B adjacently. The curved shape generating spacer 50B is connected to the adjacent rectangular float unit 50 or the curved shape generating spacer 50B using, for example, bolts and nuts.

As shown in FIG. 30, the curved shape generating spacer 50B includes a wooden scaffolding board 58 as a working board and a frame portion 59. The wooden scaffold board 58 is used to make the upper surface of the curved shape generating spacer 50B flat and to facilitate work on the float platform FP2. The wooden scaffolding board 58 has bolt mounting holes 58a for fixing to the frame portion 59.

The work plate is not limited to wood, and may be made of metal, FRP, rubber, or resin, and is preferably grating. Examples of the metal include iron, stainless steel, and aluminum. Examples of the resin include vinyl chloride, polypropylene, and polyethylene.

The frame portion 59 includes frame members 59a and 59b, a hinge 59c, a sliding plate 59e, and a sliding portion spacer 59f. A hinge 59c is arranged at each corner 57a, 57b, 57c.

The frame material 59a is for forming both sides of the frame portion 59. The hinge 59c includes a blade 59i and a shaft 59j, and the blade 59i rotates about the shaft 59j, thereby making it possible to change the angles of the corners 57a, 57b, and 57c. On each side, two frame members 59a are fixed by bolts 59g and nuts 59h at the upper and lower ends of the blades 59i of hinges 59c disposed at each corner 57a, 57b, 57c, connecting the hinges 59c. ing.

The frame material 59b is for forming the front surface of the frame portion 59. Two frame members 59b are fixed at the corner 57b at the upper and lower ends of the blades 59i of the hinge 59c with bolts 59g and nuts 59h. The frame member 59b has a rail portion 59k on which a sliding portion 59l, which will be described later, slides. The frame members 59a and 59b form the sides of the triangle.

The frame portion 59 has a sliding portion 59l at a corner portion 57c. The sliding plate 59e is combined with the sliding part spacer 59f and the blade 59i of the hinge 59c to form a sliding part 59l that slides on the rail part 59k. The sliding plate 59e is fixed to the blade 59i of the hinge 59c with a bolt 59g and a nut 59h with a sliding part spacer 59f interposed therebetween. As a result, grooves are formed at the upper and lower ends of the sliding plate 59e, forming a sliding portion 59l. By fitting the sliding portion 59l into the rail portion 59k of the upper and lower frame members 59b, the sliding portion 59l can slide on the rail portion 59k in the directions shown by arrows N19 and N20. By sliding, the lengths of the sides of the triangular shape formed by the frame member 59b can be adjusted.

As shown in FIG. 31(A), when the sliding portion 59l is slid in the direction shown by the arrow N19, the angle of the corner portion 57a becomes larger, and the angle of the corner portions 57b and 57c becomes smaller. At the same time, the length of the triangular side formed by the frame material 59b increases. Conversely, as shown in FIG. 31(B), when the sliding portion 59l is slid in the direction shown by the arrow N20, the angle of the corner portion 57a becomes smaller than the state shown in FIG. 32(A), and the angle The angles of portions 57b and 57c become larger. At the same time, the length of the triangular side formed by the frame material 59b becomes smaller.

The sliding portion 59l may be provided at the corner 57b instead of the corner 57c. Alternatively, the sliding portions 59l may be provided at multiple locations. For example, the sliding portions 59l may be provided at the corners 57b and 57c.

Note that when the lengths of the two frame members 59a are equal, the triangular shape becomes an isosceles triangle. The frame material 59b corresponds to the base of an isosceles triangle. A corner 57a between the two frame members 59a is an apex angle, and the remaining two corners 57b and 57c are base angles.

The wooden scaffold board 58 is formed to match the shape of the curved shape generating spacer 50B in which the angles of the corners 57a, 57b, and 57c are adjusted. As shown in FIG. 30, the frame members 59a and 59b have bolt mounting holes 59d at positions that match the bolt mounting holes 58a of the wooden scaffolding board 58. The wooden scaffolding board 58 and the frame portion 59 are coupled with bolts 58b. A plurality of bolt mounting holes 59d are formed in the frame material 59b so as to correspond to different shapes of the wooden scaffolding board 58.

The curved shape generating spacer 50B may have a two-layer structure like the rectangular float unit 50. In this case, the lower layer of the two-layer structure contains, for example, styrene foam for imparting buoyancy to the curved shape generating spacer 50B . This foamed polystyrene is molded to match the shape of the curved shape generating spacer 50B . The upper layer accommodates, for example, the slide mechanism 6 described in the first embodiment.

Next, referring to FIG. 32, a float platform FP3 using the curved shape generating spacer 50B shown in FIG. 31(B) is shown. The pier 10B is larger than the pier 10A. The float platform FP3 is adapted to fit the pier 10B and is configured to be able to assemble the assembly intermediate body 70C, and includes a working float 2B including the float segment 5B. The assembly intermediate body 70C has a different shape in plan view from the assembly intermediate body 70 or the assembly intermediate body 70B.

As shown in FIG. 32, the float segment 5B includes a straight portion 55 and a curved portion 56B. Two rectangular float units 50 each having a rectangular parallelepiped shape are connected to the straight portion 55 . The length of the straight portion 55 can be adjusted depending on the number of rectangular float units 50 to be connected. The rectangular float unit 50 has a square shape in plan view. On the other hand, the curved portion 56B is manufactured by combining the rectangular parallelepiped-shaped rectangular float unit 50 and the curved shape generating spacer 50B. As described above, the curved shape generating spacer 50B has a smaller angle at the corner 57a, a larger angle at the corners 57b and 57c, and a longer length of the triangular side formed by the frame material 59b than the float platform FP2. is getting smaller. Four rectangular float units 50 and three curved shape generating spacers 50B are alternately connected. By changing the number of connections of the rectangular float unit 50 and the curved shape generating spacer 50B , the angles of the corners 57a, 57b, and 57c, and the lengths of the sides, the curved shape portion 56A can be transformed into a curved shape portion 56B with a different degree of curvature. Be changed.

According to this embodiment, the same effects as the first embodiment are achieved.

Furthermore, the float segments 5A and 5B of the float platforms FP2 and FP3 are formed to match the cross-sectional shape of the piers 10A and 10B by a combination of members having simple shapes such as the rectangular float unit 50 and the curved shape generating spacer 50B. can do. Therefore, the burden of preparing the float platforms FP2 and FP3 can be reduced. Thereby, it is possible to shorten the construction period and reduce costs for constructing the temporary cofferdam structure 7.

Further, the curved shape generating spacer 50B can change the angles of the corner portions 57a, 57b, and 57c and the length of the triangular side formed by the frame material 59b by sliding the sliding portion 59l. Therefore, the curved shape generating spacer 50B and the rectangular float unit 50, which are common members, can be used to construct the float platforms FP2 and FP3 that are compatible with the piers 10A and 10B having different cross-sectional shapes, and each float platform FP2 and FP3 can be The need for preparing new parts can be reduced. Thereby, in constructing the temporary cofferdam structure 7, it is possible to shorten the construction period and reduce costs.

<Fourth embodiment>
A fourth embodiment of the present invention will be described with reference to FIG. 33. The fourth embodiment corresponds to a modification of the third embodiment. The fourth embodiment differs from the third embodiment in that a curved shape generating spacer 50C is used instead of the curved shape generating spacer 50B. In the curved shape generating spacer 50C, components having the same or similar functions as the components of the curved shape generating spacer 50B are given the same reference numerals. Regarding these, detailed explanation will be omitted.

As shown in FIG. 33, the curved shape generating spacer 50C has a quadrangular prism shape and a trapezoidal shape in plan view. The longer base of the trapezoidal shape is arranged, for example, on the side corresponding to the outside of the work floats 2A, 2B in the third embodiment, and the shorter base is arranged on the side corresponding to the inside of the work floats 2A, 2B. will be placed in The curved shape generating spacer 50C includes a wooden scaffolding board 58A as a working board and a frame portion 59A.

The wooden scaffolding board 58A is used to make the upper surface of the curved shape generating spacer 50C flat and to facilitate work thereon. The work plate is not limited to wood, and may be made of metal, FRP, rubber, or resin, and is preferably grating. Examples of the metal include iron, stainless steel, and aluminum. Examples of the resin include vinyl chloride, polypropylene, and polyethylene.

The frame portion 59A includes frame members 59a, 59b, and 59m, a hinge 59c, a sliding plate 59e, and a sliding portion spacer 59f. A hinge 59c is arranged at each of the corners 57a, 57b, 57c, and 57d. The frame material 59a is for forming both sides of the frame portion 59A. The hinge 59c includes a blade 59i and a shaft 59j, and the blade 59i rotates about the shaft 59j, thereby making it possible to change the angles of the corners 57a, 57b, 57c, and 57d. On each side, two frame members 59a are fixed by bolts 59g and nuts 59h at the upper and lower ends of the blades 59i of the hinge 59c arranged at each corner 57a, 57b, 57c, and 57d, and the hinges 59c are fixed to each other by bolts 59g and nuts 59h. It is connected.

The frame material 59b is for forming the front surface of the frame portion 59A, and forms the longer base of the trapezoidal shape. Two frame members 59b are fixed at the corner 57b at the upper and lower ends of the blades 59i of the hinge 59c with bolts 59g and nuts 59h. The frame portion 59A, like the frame portion 59, has a sliding portion 59l at the corner portion 57c. By fitting the rail portions 59k of the upper and lower frame members 59b into the sliding portion 59l, the sliding portion 59l slides on the rail portion 59k in the directions shown by arrows N19 and N20. By sliding, the length of the longer side of the trapezoidal shape formed by the frame member 59b can be adjusted. The frame members 59a, 59b, and 59m form the sides of the trapezoidal shape.

When the sliding portion 59l is slid in the direction indicated by the arrow N19, the angles of the corners 57a and 57d become larger, and the angles of the corners 57b and 57c become smaller. At the same time, the length of the longer side formed by the frame material 59b increases. Conversely, when the sliding portion 59l is slid in the direction indicated by the arrow N20, the angles of the corners 57a and 57d become smaller, and the angles of the corners 57b and 57c become larger. At the same time, the length of the longer side formed by the frame material 59b becomes smaller.

The wooden scaffolding board 58A is formed to match the shape of the frame portion 59A in plan view, with the angles of the corners 57a, 57b, 57c, and 57d being adjusted. The frame members 59a, 59b, and 59m have bolt mounting holes 59d at positions that match the bolt mounting holes 58a of the wooden scaffolding board 58A. The wooden scaffolding board 58A and the frame portion 59A are coupled with bolts 58b. A plurality of bolt attachment holes 59d are formed in the frame material 59b so as to correspond to different shapes of the wooden scaffolding board 58A.

The sliding portion 59l may be provided at the corner 57a, the corner 57b, or the corner 57d instead of the corner 57c. Further, the sliding portion 59l may be provided at multiple locations. For example, the sliding portions 59l may be provided at the corners 57b and 57c. Alternatively, the sliding portions 59l may be provided at the corners 57c and 57a. Alternatively, the sliding portions 59l may be provided at the corners 57c and 57d. Alternatively, the sliding portions 59l may be provided at the corners 57b and 57a. Alternatively, the sliding portions 59l may be provided at the corners 57b and 57d. Alternatively, the sliding portions 59l may be provided at the corners 57a and 57d. Alternatively, the sliding portions 59l may be provided at the corners 57b, 57c, and 57a. Alternatively, the sliding portions 59l may be provided at the corners 57b, 57c, and 57d. Alternatively, the sliding portions 59l may be provided at the corners 57b, 57a, and 57d. Alternatively, the sliding portions 59l may be provided at the corners 57c, 57a, and 57d. Alternatively, the sliding portions 59l may be provided at the corners 57b, 57c, 57a, and 57d.

The curved shape generating spacer 50C is not limited to a trapezoidal shape in a plan view, but may be a rectangular shape. One side of the quadrangular shape is arranged, for example, on the side corresponding to the outside of the work floats 2A, 2B in the third embodiment, and the opposite side of the side of the quadrilateral shape is arranged on the side corresponding to the inside of the work floats 2A, 2B. It is located in The length of one side of the rectangular shape is set to be greater than the length of the opposite side.

According to this embodiment, the same effects as the third embodiment are achieved.

<Fifth embodiment>
A method for constructing a temporary cofferdam structure according to a fifth embodiment of the present invention will be described with reference to FIGS. 34 and 35. The method for constructing a temporary cofferdam structure according to this embodiment is suitable for constructing the temporary cofferdam structure 7 according to the first embodiment. Components having the same or similar functions as the components of the temporary cofferdam structure 7 and the float platform FP1 used for its construction according to the first embodiment have the same reference numerals as those of the temporary cofferdam structure 7 and the float platform FP1. is attached. Regarding these, detailed explanation will be omitted. In the construction method of the temporary cofferdam structure 7 according to this embodiment, the construction process of the temporary cofferdam structure main body 7a is performed in the same manner as in the first embodiment. The process of covering the waterproof cover 7 has a difference from the first embodiment. Therefore, the process of covering the waterproof cover 7b will be mainly described below.

As shown in FIG. 34, the waterproof cover 7b connects a joint 78a formed between at least one waterproof sheet 78 and a sheet end 78d of the at least one waterproof sheet 78 to prevent water leakage from the joint 78a . It includes a waterproof fastener 79 that is openably and closably joined to the zipper. The waterproof fastener 79 corresponds to an example of a water leakage prevention joining means in the present invention.

In the process of covering the waterproof cover 7b, when the assembly intermediate body 70 is disposed at the lower part of the temporary cofferdam structure main body 7a, the covering process of the waterproof cover 7b is carried out at a predetermined location of the assembly intermediate body 70 disposed at the lower part of the temporary cofferdam structure main body 7a. At least one tarpaulin sheet 78 is installed so as to form a seam 78a between the sheet end portions 78d of at least one tarpaulin sheet 78. along the circumferential direction of the temporary cofferdam structure main body 7a, and attaching the lower part 78b of at least one waterproof sheet 78 to the reinforcing member 74, and attaching the upper part 78e of at least one waterproof sheet 78 to the waterproof fastener 79. and a temporary fixing step of temporarily fixing the assembly intermediate body 70 in an open state to a temporary fixing part 70b provided on the assembly intermediate body 70 disposed at the lower part of the temporary cofferdam structure main body 7a. In addition, the said waterproof sheet attachment part installation process, the said waterproof sheet attachment process, and the said temporary fixation process are performed in the air in parallel with the assembly process of the assembly intermediate body 70. In the temporary fixing step, the upper part 78e of at least one waterproof sheet 78 is temporarily fixed as a rolled body 78f wound into a roll shape or a folded body folded into a bellows shape with the waterproof fastener 79 opened. It is preferable to temporarily fix it to 70b.

As shown in FIG. 34, the float platform FP1 is in the second state, the upper part 78e of the waterproof sheet 78 is temporarily fixed, and the lowermost assembly intermediate body 70 (first stage) is installed on the foundation 11 of the pier 10. Then, the assembly intermediate body 70A (second stage) is stacked.

In the covering step, as shown in FIG. 35, the upper part 78e of at least one waterproof sheet 78 is temporarily fixed to an additional temporary fixing part 70Ab provided above the temporary fixing part 70b in the temporary coffering structure main body 7a. In an additional temporary fixing step, the upper part 78e of the temporarily fixed at least one waterproof sheet 78 is removed from the temporary fixing part 70b or the additional temporary fixing part 70Ab, and while closing the waterproof fastener 79, the upper part 78e of the at least one temporarily fixed waterproof sheet 78 is removed upward and the joint 78a The method further includes a joining step of joining. When repeating the stacking of the assembly intermediate bodies 70, 70A in the stacking process, the additional temporary fixing process and the bonding process are repeated as necessary to bond the joints 78a in stages. On the other hand, the float platform FP1 is in the first state, and the assembly intermediate 70A to be next stacked thereon is assembled in the air.

According to this embodiment, the same effects as the first embodiment are achieved.

Further, since the seams 78a of the waterproof sheet 78 are joined in stages, it is possible to reduce the labor of the diving operator and improve work efficiency.

<Sixth embodiment>
A method for constructing a temporary cofferdam structure according to a sixth embodiment of the present invention will be described with reference to FIGS. 36 to 38. The method for constructing a temporary cofferdam structure according to this embodiment is suitable for constructing the temporary cofferdam structure 7 described in the first embodiment. Similar to the first embodiment, the temporary cofferdam structure 7 includes a temporary cofferdam structure body 7a and a waterproof cover 7b for preventing water leakage into the interior of the temporary cofferdam structure body 7a. Further, the temporary cofferdam structure main body 7a includes assembly intermediate bodies 70 and 70A assembled around the pier 10. Components having the same or similar functions as the components of the temporary cofferdam structure 7 and the float platform FP1 used for its construction according to the first embodiment have the same reference numerals as those of the temporary cofferdam structure 7 and the float platform FP1. is attached. Regarding these, detailed explanation will be omitted. The construction method of the temporary cofferdam structure 7 according to the present embodiment includes a construction step of constructing the temporary cofferdam structure main body 7a around the pier 10, and a covering step in which the outer surface 7c of the temporary cofferdam structure main body 7a is covered with a waterproof cover 7b. It has a construction process. Also in the construction method of the temporary cofferdam structure 7 according to this embodiment, the construction process of the temporary cofferdam structure main body 7a is performed in the same manner as in the first embodiment. On the other hand, the process of covering the waterproof cover 7b has a difference from the first embodiment. Therefore, in this embodiment as well, the process of covering the waterproof cover 7b will be mainly described.

As shown in FIG. 38, the waterproof cover 7b connects a seam 78a formed between at least one waterproof sheet 78 and a sheet end 78d of the at least one waterproof sheet 78. It includes a waterproof fastener 79 that can be opened and closed to prevent water leakage from 78a . The waterproof fastener 79 corresponds to an example of a water leakage prevention joining means in the present invention.

As shown in FIG. 36, the float platform FP1 is in the first state, and the lowermost assembly intermediate body 70 (first stage ) is assembled in the air. In the case where the assembly intermediate body 70 is the assembly intermediate body 70 disposed at the lower part of the temporary cofferdam structure main body 7a, the covering step includes a predetermined covering process of the assembly intermediate body 70 disposed at the lower part of the temporary cofferdam structure main body 7a. At least one waterproof sheet 78 is installed so that a seam 78a is formed between the sheet end portions 78d of at least one waterproof sheet 78. 78 along the circumferential direction of the temporary cofferdam structure main body 7b, and attaching the lower part 78b of at least one waterproof sheet 78 to the reinforcing member 74, and attaching the upper part 78e of at least one waterproof sheet 78 to the waterproof fastener. 79 is opened and temporarily fixed to a temporary fixing part 70Bb provided at a predetermined location of the float platform FP1 so as to be extendable from the float platform FP1. The upper part 78e of at least one waterproof sheet 78 is wound around a shaft 78Bg rotatably attached to the temporary fixing part 70Bb, and is formed into a roll shape. In this way, in the temporary fixing process, the upper part 78e of at least one waterproof sheet 78 is temporarily fixed to the temporary fixing part 70Bb as a rolled body 78f wound up in a roll shape or as a folded body folded in a bellows shape. is preferred. In addition, the said waterproof sheet attachment part installation process, the said waterproof sheet attachment process, and the said temporary fixation process are performed in the air in parallel with the assembly process of the assembly intermediate body 70. Further, the reinforcing member 74 is not limited to being installed on the first stage assembly intermediate body 70, but as long as it is placed at the lower part of the temporary cofferdam structure main body 7a, it can be installed on the second stage and subsequent assembly intermediate bodies 70A. It may be installed.

As shown in FIG. 37, in the process of lowering the assembly intermediate bodies 70, 70A into the water, when lowering the assembly intermediate body 70 (first stage ) located at the lower part of the temporary cofferdam structure main body 7a, the float The platform FP1 is brought into the second state, and the upper part 78e of at least one waterproof sheet 78 is lowered into the water while being let out from the float platform FP1 . The covering step includes a joining step of joining the joint 78a upward while closing the waterproof zipper 79 underwater.

As shown in FIG. 38 , the float platform FP1 is in the second state, and the assembly intermediate bodies 70A (second stage, 3 th ) is laminated.

According to this embodiment, the same effects as the first embodiment are achieved.

Furthermore, when lowering the assembly intermediate bodies 70, 70A arranged at the lower part of the temporary cofferdam structure main body 7a, the waterproof sheet 78 is lowered while being let out from the float platform FP1 , so that the labor of the worker can be reduced. It is possible to improve work efficiency.

<Seventh embodiment>
A method for constructing a temporary cofferdam structure according to a seventh embodiment of the present invention will be described with reference to FIGS. 39 and 40. The method for constructing a temporary cofferdam structure according to this embodiment is also suitable for constructing the temporary cofferdam structure 7 according to the first embodiment. Components having the same or similar functions as the components of the temporary cofferdam structure 7 and the float platform FP1 used for its construction according to the first embodiment have the same reference numerals as those of the temporary cofferdam structure 7 and the float platform FP1. is attached. Regarding these, detailed explanation will be omitted. In the method for constructing the temporary cofferdam structure 7 according to the present embodiment, the step of covering the waterproof cover 7b is performed in the same manner as in the first embodiment . On the other hand, the construction process of the temporary cofferdam structure main body 7a has differences from the first embodiment. Therefore, in this embodiment, the construction process of the temporary cofferdam structure main body 7a will be mainly described.

As shown in FIGS. 39 and 40, similar to the first embodiment, the temporary cofferdam structure 7 includes a temporary cofferdam structure main body 7a and a waterproof structure for preventing water leakage into the interior of the temporary cofferdam structure main body 7a. A cover 7b is provided. The construction method of the temporary cofferdam structure 7 according to the present embodiment includes a construction step of constructing the temporary cofferdam structure main body 7a around the pier 10, and a covering step in which the outer surface 7c of the temporary cofferdam structure main body 7a is covered with a waterproof cover 7b. It has a construction process. The temporary cofferdam structure main body 7a includes assembly intermediate bodies 70 and 70A assembled around the pier 10.

The construction process includes a work platform installation process of installing the float platform FP1 at a predetermined height so as to surround the pier 10, as in the first embodiment. Float platform FP1 corresponds to an example of a work platform in the present invention. The float platform FP1 can changeably assume a contracted state and an expanded state around the pier 10, and based on this, the first floating platform FP1 can assemble and hold the assembly intermediate bodies 70, 70A thereon in the air. and a second state in which the assembly intermediate bodies 70, 70A can be passed through and lowered into water. Further, similarly to the first embodiment, the construction step sets the float platform FP1 in the first state, and when the assembly intermediate bodies 70 and 70A are the lowest assembly intermediate bodies 70, The assembly process includes an assembly step of assembling the lower assembly intermediate body 70.

The construction process of the temporary cofferdam structure main body 7a in this embodiment differs from the first embodiment in the following points, and these will be explained. That is, as shown in FIG. 39, in the construction step, the lowermost assembly intermediate 70 assembled in the assembly step is placed on the floating platform FP1 in the second state, and the assembly intermediate 70 is placed thereon in the air. , 70A, a lowering process in which the additional assembly intermediate 70A is lowered in the direction indicated by arrow N18 to a height where it can be assembled, and an additional assembly in which the additional assembly intermediate 70A is directly assembled on top of the lowermost assembly intermediate 70. It has a process. Note that this additional assembly step includes a step of directly assembling the additional assembly intermediate 70A on the laminate of the assembly intermediate 70 and the additional assembly intermediate 70A. In the assembly process and the additional assembly process, the liner plates 73 are connected without intervening a band-shaped waterproof packing.

Further, as shown in FIG. 40, while the float platform FP1 is in the second state, the construction process is continued with the additional assembly process until the lowermost assembly intermediate body 70 bottoms out on the foundation 11 of the pier 10. The process includes a stacking process in which the assembly intermediate bodies 70 and 70A are stacked by repeating the lowering process, and an installation process in which the lowermost assembly intermediate body 70 that has landed on the bottom is installed on the foundation 11 of the pier 10 .

In this embodiment, the waterproof cover 7b connects the seam 78a formed between the at least one waterproof sheet 78 and the sheet end 78d of the at least one waterproof sheet 78 from the seam 78a. a waterproof fastener 79 that can be opened and closed to prevent water leakage. Further, in this embodiment, the waterproof cover 7b covering step is performed in the same manner as in the first embodiment from the state shown in FIG. 40 after the step of laminating the assembly intermediate body 70 and the additional assembly intermediate body 70A.

According to this embodiment, the same effects as the first embodiment are achieved. The construction method of this embodiment is particularly excellent when the height of the temporary cofferdam structure 7 is low, and can be constructed in a short time.

<Eighth embodiment>
A method for constructing a temporary cofferdam structure according to the eighth embodiment of the present invention will be described with reference to FIGS. 41 and 42. The method for constructing a temporary cofferdam structure according to this embodiment is also suitable for constructing the temporary cofferdam structure 7 according to the first embodiment. Components having the same or similar functions as the components of the temporary cofferdam structure 7 and the float platform FP1 used for its construction according to the first embodiment have the same reference numerals as those of the temporary cofferdam structure 7 and the float platform FP1. is attached. Regarding these, detailed explanation will be omitted.

The construction method of the temporary cofferdam structure 7 according to this embodiment has differences from the first embodiment in the construction process of the temporary cofferdam structure main body 7a and the covering process of the waterproof cover 7b. On the other hand, the construction process of the temporary cofferdam structure main body 7a of this embodiment is performed in the same manner as in the seventh embodiment. That is, the assembly process includes assembling the lowermost assembly intermediate body 70 (first stage ) on the float platform FP1 in the first state. Additional assembly in which an additional assembly intermediate 70A (second stage ) is directly assembled in the air on top of the suspended lowermost assembly intermediate 70 (first stage) with the float platform FP1 in the second state. It has a process. Therefore, a detailed explanation of the construction process of the temporary cofferdam structure main body 7a will be omitted.

As shown in FIG. 41, in this embodiment, the waterproof cover 7b connects a seam 78a formed between at least one waterproof sheet 78 and a sheet end 78d of the at least one waterproof sheet 78 from the seam 78a. It includes a waterproof fastener 79 that can be opened and closed to prevent water leakage. The waterproof fastener 79 corresponds to an example of a water leakage prevention joining means in the present invention.

In this embodiment, the process of covering the waterproof cover 7b is carried out when the assembly intermediate bodies 70, 70A are the assembly intermediate bodies 70, 70A disposed at the lower part of the temporary cofferdam structure body 7a. A waterproof sheet attachment part installation step in which a reinforcing member 74 serving as a waterproof sheet attachment part is provided at a predetermined location of the assembly intermediate body 70, 70A disposed at the lower part of the assembly, and between the sheet ends 78d of at least one waterproof sheet 78. At least one waterproof sheet 78 is arranged along the circumferential direction of the temporary cofferdam structure main body 7a so as to form a seam 78a, and the lower part 78b of the at least one waterproof sheet 78 is attached to the reinforcing member 74. and a temporary fixing step of temporarily fixing the upper part 78e of at least one waterproof sheet 78 to the temporary fixing part 70b provided on the assembly intermediate body 70, 70A with the waterproof fastener 79 opened. In addition, the said waterproof sheet attachment part installation process, the said waterproof sheet attachment process, and the said temporary fixing process are performed in the air in parallel with the said assembly process or the said additional assembly process.

As shown in FIG. 41, in the covering step of this embodiment, the upper part 78e of at least one waterproof sheet 78 is attached to an additional temporary fixing part 70Ab provided above the temporary fixing part 70b in the temporary cofferdam structure main body 7a. It has an additional temporary fixing step. This point is different from the first embodiment, and will be explained below. That is, with the float platform FP1 in the second state, the upper part 78e of at least one waterproof sheet 78 temporarily fixed to the lowermost assembly intermediate body 70 (first stage) is released, and then the adjacent A joining process of joining the seams 78a while extending the waterproof sheet 78 upward as shown by the arrow N22, and adding temporary fixing to the additional temporary fixing part 70Ab provided on the additional assembly intermediate body 70A (second stage). and an additional temporary fixing step. The additional temporary fixing part 70Ab is provided above the temporary fixing part 70b in the temporary closing structure main body 7a. As shown in FIG. 41, additional temporary fixation can also be performed in air. In the temporary fixing process or the additional temporary fixing process, the upper part 78e of at least one waterproof sheet 78 is temporarily fixed to the temporary fixing part 70b as a rolled body 78f wound into a roll shape or a folded body folded into a bellows shape. It is preferable to do so.

As shown in FIG. 42, an additional assembly intermediate 70A (third stage ) is stacked on the additional assembly intermediate 70A (second stage), which is further lowered, and the lowest assembly intermediate 70 (first stage) is stacked on the additional assembly intermediate 70A (second stage). ) is installed on the foundation 11 of the pier 10. Release the temporary fixation of the upper part 78e of the waterproof sheet 78 temporarily fixed to the additional temporary fixing part 70Ab to the additional assembly intermediate body 70A (second stage), and move it upward in the direction shown by arrow N22 while closing the waterproof fastener 79. The joints 78a are joined in stages by performing a joining process in which the joints 78a are joined toward the end. As shown in FIG. 42, the stepwise bonding process can also be performed in air.

According to this embodiment, the same effects as the first embodiment are achieved.

Further, since the seams 78a of the waterproof sheet 78 are joined in stages, it is possible to reduce the labor of the diving operator and improve work efficiency.

<Ninth embodiment>
A method for constructing a temporary cofferdam structure according to a ninth embodiment of the present invention will be described with reference to FIGS. 43 and 44. The method for constructing a temporary cofferdam structure according to this embodiment is also suitable for constructing the temporary cofferdam structure 7 according to the first embodiment. Components having the same or similar functions as the components of the temporary cofferdam structure 7 and the float platform FP1 used for its construction according to the first embodiment have the same reference numerals as those of the temporary cofferdam structure 7 and the float platform FP1. is attached. Regarding these, detailed explanation will be omitted. The construction method of the temporary cofferdam structure 7 according to this embodiment has differences from the first embodiment in the construction process of the temporary cofferdam structure main body 7a and the covering process of the waterproof cover 7b.

As shown in FIGS. 43 and 44, similarly to the first embodiment, the temporary cofferdam structure 7 includes a temporary cofferdam structure main body 7a and a waterproof structure for preventing water leakage into the interior of the temporary cofferdam structure main body 7a. A cover 7b is provided. The construction method of the temporary cofferdam structure 7 according to the present embodiment includes a construction step of constructing the temporary cofferdam structure main body 7a around the pier 10, and a covering step in which the outer surface 7c of the temporary cofferdam structure main body 7a is covered with a waterproof cover 7b. It has a construction process. The temporary cofferdam structure main body 7a includes assembly intermediate bodies 70 and 70A assembled around the pier 10.

The construction process includes a work platform installation process of installing the float platform FP1 at a predetermined height so as to surround the pier 10, as in the first embodiment. Float platform FP1 corresponds to an example of a work platform in the present invention. The float platform FP1 can changeably assume a contracted state and an expanded state around the pier 10, and based on this, the first floating platform FP1 can assemble and hold the assembly intermediate bodies 70, 70A thereon in the air. and a second state in which the assembly intermediate bodies 70, 70A can be passed through and lowered into water.

Further, in the construction step, when the float platform FP1 is in the first state and the assembly intermediates 70 and 70A are the lowermost assembly intermediates 70, the lowermost assembly intermediate 70 is assembled on the float platform FP1. It has an assembly process. Further, as shown in FIG. 43, in the construction step, the float platform FP1 is brought into the second state, and an additional intermediate assembly 70A of the assembly intermediates 70, 70A can be assembled in the air on top of the float platform FP1. It has a lowering step of lowering it to a height into the water in the direction shown by arrow N18, and an additional assembly step of directly assembling an additional assembly intermediate 70A on top of the lowermost assembly intermediate 70. These steps are different from the first embodiment.

Further, as shown in FIG. 44, in the construction process, the assembly intermediate body 70 is repeated by repeating the additional assembly process and the lowering process until the lowest assembly intermediate body 70 touches the foundation 11 of the pier 10. , 70A, and an installation step of installing the lowermost assembly intermediate body 70 that has reached the bottom on the foundation 11 of the pier 10. These steps are different from the first embodiment.

As shown in FIG. 43, the waterproof cover 7b connects a seam 78a formed between at least one waterproof sheet 78 and a sheet end 78d of the at least one waterproof sheet 78. It includes a waterproof fastener 79 that can be opened and closed to prevent water from leaking from 78a . The waterproof fastener 79 corresponds to an example of a water leakage prevention joining means in the present invention.

In the case where the assembly intermediate bodies 70, 70A are assembly intermediate bodies 70, 70A disposed at the lower part of the temporary cofferdam structure main body 7a, the covering step is performed by A waterproof sheet attachment part installation step in which a reinforcing member 74 serving as a waterproof sheet attachment part is provided at a predetermined location of the body 70, 70A, and a joint 78a is formed between the sheet end 78d of at least one waterproof sheet 78. a waterproof sheet attaching step of arranging at least one waterproof sheet 78 along the circumferential direction of the temporary cofferdam structure main body 7a and attaching a lower part 78b of the at least one waterproof sheet 78 to the reinforcing member 74; 78 is temporarily fixed to a temporary fixing part 70Bb provided at a predetermined location of the float platform FP1 with the waterproof fastener 79 opened so as to be extendable from the float platform FP1. These steps are different from the first embodiment. The upper part 78e of at least one waterproof sheet 78 is wound around a shaft 78Bg rotatably attached to the temporary fixing part 70Bb, and is formed into a roll shape. In addition, the said waterproof sheet attachment part installation process, the said waterproof sheet attachment process, and the said temporary fixation process are performed in the air in parallel with the assembly process of the assembly intermediate bodies 70 and 70A.

In the lamination process, when lowering the assembly intermediate bodies 70, 70A arranged at the lower part of the temporary cofferdam structure main body 7a, the upper part 78e of at least one waterproof sheet 78 is lowered while being let out from the float platform FP1. This step is different from the first embodiment. The covering step includes a joining step of joining the joint 78a upward while closing the waterproof zipper 79 underwater.

Note that the installation location of the temporary fixing portion 70Bb is not limited to the float platform FP1. The temporary fixing part 70Bb may be provided on the underwater structure side. Specifically, it can be provided, for example, on the pier 10, the pier upper part 12, and the bridge girder 13 of the bridge 1.

According to this embodiment, the same effects as the first embodiment are achieved.

Furthermore, when lowering the assembly intermediate body 70 disposed at the lower part of the temporary cofferdam structure main body 7a, the waterproof sheet 78 is lowered while being paid out from the float platform FP1 , so that the labor of the worker can be reduced. It is possible to improve work efficiency.

The present invention is not limited to the content of the embodiments described above. The design of the temporary cofferdam structure, the method of constructing the temporary cofferdam structure, and the specific configuration of the platform used therein according to the present invention can be changed in various ways. Further, the features shown in each embodiment described above can be applied to other embodiments as long as they do not contradict each other.

In the above embodiment, construction of a temporary cofferdam structure when repairing a bridge pier in a river has been described. The present invention is also applicable to underwater structures other than bridge piers. Specific examples of underwater structures include water gates and the like. It goes without saying that the present invention can be applied not only to underwater structures such as bridge piers in rivers, but also to the construction of temporary cofferdam structures during the repair of underwater structures including bridge piers in the sea, lakes, etc.

The number of layers of assembly intermediate bodies of the temporary cofferdam structure can be set as appropriate. Furthermore, the number of laminated liner plates of the assembly intermediate can also be arbitrarily set to one layer, two layers, three layers, four layers, five layers, etc. Further, the number of liner plates used in the circumferential direction can also be set arbitrarily.

The waterproof sheet attachment part may be provided at the upper part of the temporary cofferdam structure body instead of at the lower part of the temporary cofferdam structure body. In this case, the waterproof cover is in a state in which the upper part of at least one waterproof sheet is attached to the waterproof sheet attachment part, the lower part of the at least one waterproof sheet is pulled down, and the waterproof zipper is pulled down and closed. , covering the outer surface of the temporary cofferdam structure body.

The water leakage prevention joining means is not limited to a waterproof fastener, and can be modified in various ways as long as it can join the joints between the sheet ends of the waterproof sheet so as to prevent water leakage. Another example of the water leakage prevention joining means is, for example, using bolts to fasten the sheet ends of the waterproof sheet to the temporary cofferdam structure body.

The working platform may be provided all around the pier at a predetermined height. Preferably, the predetermined height is a position higher than the water surface. The outer peripheral part of this platform can be cut off to a required length or bent, and based on this, the assembly intermediate body of the temporary cofferdam structure can be assembled in an enlarged state and the assembly intermediate body can be assembled on it. It can be in a reduced state where it can be passed through or lowered.

The shape of the curved shape generating spacer described in the above third and fourth embodiments in plan view is not limited to a triangular shape or a quadrangular shape like the curved shape generating spacers 50B and 50C . It may be pentagonal, hexagonal, heptagonal, octagonal, or more polygonal. This polygonal shape has at least three corners and at least three sides connecting each corner of the at least three corners in a plan view. Each of the corners is configured to be able to change an angle, at least two of the at least three corners are located outside the work float, and at least one corner is located inside the work float. The side that connects the at least two corners arranged on the outside of the work float is configured to be changeable in length, and connects the angle of each corner and the at least two corners. By changing the length of the side, the degree of curvature of the curved portion is adjusted.

A shaped steel such as L-shaped steel can also be used as the curved shape generating spacer. For example, an L-shaped steel cut to an appropriate length may be directly fixed to the rectangular float unit 50 using bolts or the like so that the curved portion has a desired degree of curvature.

FP1, FP2, FP3 Float platform (work platform)
10, 10A, 10B Pier (underwater structure)
7 Temporary coffering structure 7a Temporary coffering structure main body 7b Waterproof cover 7c Outer surface 70, 70A, 70B, 70C Assembly intermediate bodies 70b, 70Bb Temporary fixing section 70Ab Additional temporary fixing section 73 Liner plate 73c Bolt 74 Reinforcing member (waterproof sheet mounting part)
74d Flange (flange part of H-beam steel)
75 Underwater concrete 75a Upper surface 78, 78A of underwater concrete Waterproof sheet 78a Joint 78b Lower part 78e of waterproof sheet Upper part 78f of waterproof sheet Rolling body 79 Waterproof fastener (leakage prevention joining means)
9 Clamp

Claims (13)

A construction method for a temporary cofferdam structure constructed around an underwater structure, the method comprising:
The temporary cofferdam structure includes a temporary cofferdam structure body and a waterproof cover for preventing water leakage into the interior of the temporary cofferdam structure body,
a construction step of constructing the temporary cofferdam structure body around the underwater structure;
a covering step of covering the outer surface of the temporary cofferdam structure body with the waterproof cover,
The temporary cofferdam structure body includes an assembly intermediate assembled around the underwater structure ,
The construction step can changeably take a contracted state and an expanded state around the underwater structure , and based on this, the first assembly is capable of assembling and holding the assembly intermediate thereon in air. and a second state in which the assembly intermediate can be passed through and lowered into the water. A work platform is installed at a predetermined height so as to surround the underwater structure. a platform installation step; an assembly step in which the work platform is in the first state and the assembly intermediate is assembled; a lowering step in which the work platform is in the second state and the assembly intermediate is lowered into water; an installation step of installing the assembly intermediate body on the foundation of the underwater structure when the assembly intermediate body lowered into the water is placed at the lowest level of the temporary cofferdam structure body ; and the assembly step; a stacking step of stacking the assembly intermediate bodies until the temporary cofferdam structure body reaches a desired height by repeating the lowering step as necessary;
The waterproof cover includes at least one waterproof sheet and a water leak prevention joining means that connects the joint formed between the sheet end portion of the at least one waterproof sheet in an openable and closable manner so as to prevent water leakage from the joint. and,
In the case where the assembly intermediate body is an assembly intermediate body disposed at a lower part of the temporary cofferdam structure body, the covering step includes covering a predetermined location of the assembly intermediate body disposed at the lower part of the temporary cofferdam structure body. a waterproof sheet attaching part installation step of providing a tarpaulin attaching part to the temporary cofferdam structure body, and the at least one tarpaulin sheet is attached to the temporary cofferdam structure body so as to form the seam between the sheet ends of the at least one tarpaulin sheet. a step of attaching a lower part of the at least one tarpaulin sheet to the tarpaulin attachment part; a temporary fixing step of temporarily fixing to a temporary fixing part provided on an assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body,
In the covering step, the upper part of the at least one waterproof sheet temporarily fixed to the temporary fixing part is removed from the temporary fixing part underwater, and the joint is opened upward while closing the water leakage prevention joint means. A method for constructing a temporary cofferdam structure, further comprising a joining step of joining. 2. The method for constructing a temporary cofferdam structure according to claim 1, wherein the waterproof sheet attaching part installation step, the waterproof sheet attaching step, and the temporary fixing step are performed in parallel with the assembling step in air. The at least one waterproof sheet is configured to float or float in water,
The method for constructing a temporary cofferdam structure according to claim 1 or 2, wherein in the joining step, after removing the at least one waterproof sheet from the temporary fixing part, the joint is joined while floating or floating in water. . In the temporary fixing step, with the leakage prevention joining means open, the upper part of the at least one waterproof sheet is rolled up into a roll or a folded body into a bellows shape. The method for constructing a temporary cofferdam structure according to any one of claims 1 to 3, wherein the temporary cofferdam structure is temporarily fixed to a fixed part. The water leakage prevention joining means is a waterproof fastener provided at the joint,
The method for constructing a temporary cofferdam structure according to any one of claims 1 to 4, wherein in the joining step, the joint is joined by closing the waterproof fastener. In the assembly process, the wall part of the pre-assembly intermediate body is formed by connecting the liner plates in the circumferential direction and the vertical direction, and in the waterproof sheet attachment part installation process, the liner plates are arranged at the lower part of the temporary cofferdam structure main body. The waterproof sheet attachment part is installed at the predetermined location on the wall of the assembly intermediate body using H-shaped steel, and in the waterproof sheet attachment step, bolts or clamps are attached to the flange part of the H-shaped steel. The method for constructing a temporary cofferdam structure according to any one of claims 1 to 5, wherein the lower part of the at least one waterproof sheet is attached using a method. 7. The method for constructing a temporary cofferdam structure according to claim 6, wherein in the assembling step, the liner plate is connected to the portion covered with the waterproof cover without intervening a band-shaped waterproof packing. further comprising an underwater concrete placing step of placing underwater concrete for water-stopping inside the assembly intermediate installed on the foundation of the underwater structure ,
The temporary cofferdam structure according to claim 7, wherein in the underwater concrete placing step, the underwater concrete is placed so that the upper surface of the underwater concrete is at a position that is the same as or higher than the height of the waterproof sheet attachment part. construction method. A construction method for a temporary cofferdam structure constructed around an underwater structure, the method comprising:
The temporary cofferdam structure includes a temporary cofferdam structure body and a waterproof cover for preventing water leakage into the interior of the temporary cofferdam structure body,
a construction step of constructing the temporary cofferdam structure body around the underwater structure;
a covering step of covering the outer surface of the temporary cofferdam structure body with the waterproof cover,
The temporary cofferdam structure body includes an assembly intermediate assembled around the underwater structure ,
The construction step can changeably take a contracted state and an expanded state around the underwater structure , and based on this, the first assembly is capable of assembling and holding the assembly intermediate thereon in air. and a second state in which the assembly intermediate can be passed through and lowered into the water. A work platform is installed at a predetermined height so as to surround the underwater structure. a platform installation step; an assembly step in which the work platform is in the first state and the assembly intermediate is assembled; a lowering step in which the work platform is in the second state and the assembly intermediate is lowered into water; an installation step of installing the assembly intermediate body on the foundation of the underwater structure when the assembly intermediate body lowered into the water is placed at the lowest level of the temporary cofferdam structure body ; and the assembly step; a stacking step of stacking the assembly intermediate bodies until the temporary cofferdam structure body reaches a desired height by repeating the lowering step as necessary;
The waterproof cover includes at least one waterproof sheet and a water leak prevention joining means that connects the joint formed between the sheet end portion of the at least one waterproof sheet in an openable and closable manner so as to prevent water leakage from the joint. and,
In the case where the assembly intermediate body is an assembly intermediate body disposed at a lower part of the temporary cofferdam structure body, the covering step includes covering a predetermined location of the assembly intermediate body disposed at the lower part of the temporary cofferdam structure body. a waterproof sheet attaching part installation step of providing a tarpaulin attaching part to the temporary cofferdam structure body, and the at least one tarpaulin sheet is attached to the temporary cofferdam structure body so as to form the seam between the sheet ends of the at least one tarpaulin sheet. a step of attaching a lower part of the at least one tarpaulin sheet to the tarpaulin attachment part; a temporary fixing step of temporarily fixing to a temporary fixing part provided on an assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body,
The covering step includes an additional temporary fixing step of temporarily fixing the upper part of the at least one waterproof sheet to an additional temporary fixing part provided above the temporary fixing part in the temporary cofferdam structure body; a joining step of releasing the temporary fixing of the upper part of at least one waterproof sheet, and joining the joint toward the additional temporary fixing part while closing the water leakage prevention joining means; A method for constructing a temporary cofferdam structure, further comprising a repeating step of joining the joints in stages by repeating the fixing step and the joining step. A construction method for a temporary cofferdam structure constructed around an underwater structure, the method comprising:
The temporary cofferdam structure includes a temporary cofferdam structure body and a waterproof cover for preventing water leakage into the interior of the temporary cofferdam structure body,
a construction step of constructing the temporary cofferdam structure body around the underwater structure;
a covering step of covering the outer surface of the temporary cofferdam structure body with the waterproof cover,
The temporary cofferdam structure body includes an assembly intermediate assembled around the underwater structure ,
The construction step can changeably take a contracted state and an expanded state around the underwater structure , and based on this, the first assembly is capable of assembling and holding the assembly intermediate thereon in air. and a second state in which the assembly intermediate can be passed through and lowered into the water. A work platform is installed at a predetermined height so as to surround the underwater structure. a platform installation step; an assembly step in which the work platform is in the first state and the assembly intermediate is assembled; a lowering step in which the work platform is in the second state and the assembly intermediate is lowered into water; an installation step of installing the assembly intermediate body on the foundation of the underwater structure when the assembly intermediate body lowered into the water is placed at the lowest level of the temporary cofferdam structure body ; and the assembly step; a stacking step of stacking the assembly intermediate bodies until the temporary cofferdam structure body reaches a desired height by repeating the lowering step as necessary;
The waterproof cover includes at least one waterproof sheet and a water leak prevention joining means that connects the joint formed between the sheet end portion of the at least one waterproof sheet in an openable and closable manner so as to prevent water leakage from the joint. and,
In the case where the assembly intermediate body is an assembly intermediate body disposed at a lower part of the temporary cofferdam structure body, the covering step includes covering a predetermined location of the assembly intermediate body disposed at the lower part of the temporary cofferdam structure body. a waterproof sheet attaching part installation step of providing a tarpaulin attaching part to the temporary cofferdam structure body, and the at least one tarpaulin sheet is attached to the temporary cofferdam structure body so as to form the seam between the sheet ends of the at least one tarpaulin sheet. a step of attaching a lower part of the at least one tarpaulin sheet to the tarpaulin attachment part; a temporary fixing step of temporarily fixing the work platform to a temporary fixing part provided at a predetermined location of the work platform so as to be removable from the work platform;
In the lowering step, when lowering the assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body, lowering the upper part of the at least one waterproof sheet while letting it out from the work platform,
The method for constructing a temporary cofferdam structure, wherein the covering step further includes a joining step of joining the joint upwardly while closing the leakage prevention joining means underwater. A construction method for a temporary cofferdam structure constructed around an underwater structure, the method comprising:
The temporary cofferdam structure includes a temporary cofferdam structure body and a waterproof cover for preventing water leakage into the interior of the temporary cofferdam structure body,
a construction step of constructing the temporary cofferdam structure body around the underwater structure;
a covering step of covering the outer surface of the temporary cofferdam structure body with the waterproof cover,
The temporary cofferdam structure body includes an assembly intermediate assembled around the underwater structure ,
The construction step can changeably take a contracted state and an expanded state around the underwater structure , and based on this, the first assembly is capable of assembling and holding the assembly intermediate thereon in air. and a second state in which the assembly intermediate can be passed through and lowered into the water. A work platform is installed at a predetermined height so as to surround the underwater structure. a platform installation step; an assembly step of setting the work platform in the first state and assembling the lowermost assembly intermediate on the work platform when the assembly intermediate is the lowermost assembly intermediate; a lowering step of bringing the work platform into the second state and using the lowermost assembly intermediate as a support to lower an additional assembly intermediate among the assembly intermediates onto it to a height at which it can be assembled in the air; an additional assembly step of assembling the additional assembly intermediate on the lowermost assembly intermediate using the lowermost assembly intermediate as the support; and an additional assembly step necessary until the lowermost assembly intermediate reaches the bottom of the underwater structure. a stacking step of stacking the assembly intermediates by repeating the lowering step and the additional assembly step accordingly; and an installation step of installing the lowermost assembly intermediate that has landed on the bottom on the foundation of the underwater structure. and,
The waterproof cover includes at least one waterproof sheet and a water leak prevention joining means that connects the joint formed between the sheet end portion of the at least one waterproof sheet in an openable and closable manner so as to prevent water leakage from the joint. and,
The covering step includes a step of installing a waterproof sheet attachment portion at a predetermined location of the assembly intermediate body that is disposed below the temporary cofferdam structure main body among the assembly intermediate bodies, and a step of installing a waterproof sheet attachment portion in the at least one waterproofing structure. The at least one waterproof sheet is arranged along the circumferential direction of the temporary cofferdam structure body so as to form the seam between the sheet ends of the sheets, and the lower part of the at least one waterproof sheet is connected to the waterproof sheet. a step of attaching a tarpaulin sheet to a sheet attachment part; and a step of attaching a tarpaulin sheet to the assembly intermediate body disposed at the lower part of the temporary cofferdam structure body with the upper part of the at least one tarpaulin sheet opened at the leakage prevention joining means. A temporary fixing step of temporarily fixing it to the fixing part,
The covering step includes releasing the temporary fixation of the upper part of the at least one waterproof sheet temporarily fixed to the temporary fixing part underwater, and joining the joints upward while closing the leakage prevention joining means. A method for constructing a temporary cofferdam structure, further comprising a joining step. A construction method for a temporary cofferdam structure constructed around an underwater structure, the method comprising:
The temporary cofferdam structure includes a temporary cofferdam structure body and a waterproof cover for preventing water leakage into the interior of the temporary cofferdam structure body,
a construction step of constructing the temporary cofferdam structure body around the underwater structure;
a covering step of covering the outer surface of the temporary cofferdam structure body with the waterproof cover,
The temporary cofferdam structure body includes an assembly intermediate assembled around the underwater structure ,
The construction step can changeably take a contracted state and an expanded state around the underwater structure , and based on this, the first assembly is capable of assembling and holding the assembly intermediate thereon in air. and a second state in which the assembly intermediate can be passed through and lowered into the water. A work platform is installed at a predetermined height so as to surround the underwater structure. a platform installation step; an assembly step of setting the work platform in the first state and assembling the lowermost assembly intermediate on the work platform when the assembly intermediate is the lowermost assembly intermediate; a lowering step of bringing the work platform into the second state and using the lowermost assembly intermediate as a support to lower an additional assembly intermediate among the assembly intermediates onto it to a height at which it can be assembled in the air; an additional assembly step of assembling the additional assembly intermediate on the lowermost assembly intermediate using the lowermost assembly intermediate as the support; and an additional assembly step necessary until the lowermost assembly intermediate reaches the bottom of the underwater structure. a stacking step of stacking the assembly intermediates by repeating the lowering step and the additional assembly step accordingly; and an installation step of installing the lowermost assembly intermediate that has landed on the bottom on the foundation of the underwater structure. and,
The waterproof cover includes at least one waterproof sheet and a water leak prevention joining means that connects the joint formed between the sheet end portion of the at least one waterproof sheet in an openable and closable manner so as to prevent water leakage from the joint. and,
The covering step includes a step of installing a waterproof sheet attachment portion at a predetermined location of the assembly intermediate body that is disposed below the temporary cofferdam structure main body among the assembly intermediate bodies, and a step of installing a waterproof sheet attachment portion in the at least one waterproofing structure. The at least one waterproof sheet is arranged along the circumferential direction of the temporary cofferdam structure body so as to form the seam between the sheet ends of the sheets, and the lower part of the at least one waterproof sheet is connected to the waterproof sheet. a step of attaching a tarpaulin sheet to a sheet attachment part; and a step of attaching a tarpaulin sheet to the assembly intermediate body disposed at the lower part of the temporary cofferdam structure body with the upper part of the at least one tarpaulin sheet opened at the leakage prevention joining means. A temporary fixing step of temporarily fixing it to the fixing part,
The covering step includes an additional temporary fixing step of temporarily fixing the upper part of the at least one waterproof sheet to an additional temporary fixing part provided above the temporary fixing part in the temporary cofferdam structure body; a joining step of releasing the temporary fixing of the upper part of at least one waterproof sheet, and joining the joint toward the additional temporary fixing part while closing the water leakage prevention joining means; A method for constructing a temporary cofferdam structure, further comprising a repeating step of joining the joints in stages by repeating the fixing step and the joining step. A construction method for a temporary cofferdam structure constructed around an underwater structure, the method comprising:
The temporary cofferdam structure includes a temporary cofferdam structure body and a waterproof cover for preventing water leakage into the interior of the temporary cofferdam structure body,
a construction step of constructing the temporary cofferdam structure body around the underwater structure;
a covering step of covering the outer surface of the temporary cofferdam structure body with the waterproof cover,
The temporary cofferdam structure body includes an assembly intermediate assembled around the underwater structure ,
The construction step can changeably take a contracted state and an expanded state around the underwater structure , and based on this, the first assembly is capable of assembling and holding the assembly intermediate thereon in air. and a second state in which the assembly intermediate can be passed through and lowered into the water. A work platform is installed at a predetermined height so as to surround the underwater structure. a platform installation step; an assembly step of setting the work platform in the first state and assembling the lowermost assembly intermediate on the work platform when the assembly intermediate is the lowermost assembly intermediate; a lowering step of bringing the work platform into the second state and using the lowermost assembly intermediate as a support to lower an additional assembly intermediate among the assembly intermediates onto it to a height at which it can be assembled in the air; an additional assembly step of assembling the additional assembly intermediate on the lowermost assembly intermediate using the lowermost assembly intermediate as the support; and an additional assembly step necessary until the lowermost assembly intermediate reaches the bottom of the underwater structure. a stacking step of stacking the assembly intermediates by repeating the lowering step and the additional assembly step accordingly; and an installation step of installing the lowermost assembly intermediate that has landed on the bottom on the foundation of the underwater structure. and,
The waterproof cover includes at least one waterproof sheet and a water leak prevention joining means that connects the joint formed between the sheet end portion of the at least one waterproof sheet in an openable and closable manner so as to prevent water leakage from the joint. and,
The covering step includes a step of installing a waterproof sheet attachment portion at a predetermined location of the assembly intermediate body that is disposed below the temporary cofferdam structure main body among the assembly intermediate bodies, and a step of installing a waterproof sheet attachment portion in the at least one waterproofing structure. The at least one waterproof sheet is arranged along the circumferential direction of the temporary cofferdam structure body so as to form the seam between the sheet ends of the sheets, and the lower part of the at least one waterproof sheet is connected to the waterproof sheet. a step of attaching a tarpaulin sheet to a sheet attachment part, and allowing the upper part of the at least one tarpaulin sheet to be fed out from the work platform to a temporary fixing part provided at a predetermined location of the work platform with the water leakage prevention joining means open. a temporary fixing step of temporarily fixing;
In the lowering step, when lowering the assembly intermediate body disposed at the lower part of the temporary cofferdam structure main body, lowering the upper part of the at least one waterproof sheet while letting it out from the work platform,
The method for constructing a temporary cofferdam structure, wherein the covering step further includes a joining step of joining the joint upwardly while closing the leakage prevention joining means underwater.

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