JP2008297749A - Cofferdam construction method, cut-off structure, and cofferdam structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cofferdam construction method at a great application water depth, and to reduce a work burden on a worker, and to shorten a construction period, by reducing diving operation steps, in the cofferdam construction method. <P>SOLUTION: A cut-off structure 30 has a constitution in which first and second annular elastic bodies 32 and 33 are arranged in a bolt-connected state in a supporting frame 31 arranged at the lower end of a cut-off wall 11. The first and second annular elastic bodies 32 and 33 in the state of being pressed against an anchoring surface of a footing 51 are deformed in such a shape that lower ends are crushed, so as to be brought into close contact with the anchoring surface of the footing 51. An injection pipe 14 communicating with a section from an upper end of the cut-off wall 11 to a lower end thereof is provided inside the cut-off wall 11. A filler is injected into a space 34 between the first and second annular elastic bodies 32 and 33 of the cut-off structure 30 on the lower end side of the cut-off wall 11, from the upper end side of the cut-off wall 11 via the injection pipe 14. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a temporary closing method for forming a work space around an underwater structure by enclosing the underwater structure with a temporary closing structure and then draining the temporary closing structure, the temporary closing structure, and the temporary closing structure. The present invention relates to a waterproof structure of a structure.

As a method of maintenance, inspection, repair or seismic reinforcement work for existing underwater structures such as river piers constructed in the water of rivers, etc., after enclosing the underwater structure with a temporary closing structure, There is known a temporary deadline method for draining the deadline structure and forming a work space around the underwater structure (see, for example, Patent Documents 1 to 3). In such a temporary closing method, as a method for stopping the inside of the temporary closing structure, for example, a method of disposing a sealing material or a waterproof packing between the temporary closing structure and the footing (for example, Patent Document 1). And a method for stopping water by placing underwater concrete (for example, see Patent Document 2).
Japanese Patent Laid-Open No. 11-21908 JP 2004-316133 A JP-A-2005-299222

  However, the conventional techniques described in Patent Documents 1 and 3 described above have a limit in application water depth because it is difficult to obtain a high water-stopping effect only by water-stopping using a sealing material or water-stopping packing. Moreover, since the prior art described in the above-mentioned Patent Document 2 is forced to perform underwater diving work with a heavy work load such as placing underwater concrete, there is a problem that the burden on the operator is large. Since the work is inefficient and takes a long time, there is a problem that the work period of the repair work by the temporary closing method is prolonged.

  The present invention has been made in view of such a situation, and its problem is to realize a temporary closing method with a deep application water depth, to reduce the diving work process in the temporary closing method, and to reduce the work burden on the operator. It is to reduce the construction period and the construction period.

  To achieve the above object, according to a first aspect of the present invention, after an underwater structure is surrounded by a temporary closing structure, the temporary closing structure is drained to form a work space around the underwater structure. The water stop structure provided at the lower end of the water stop wall of the temporary stop structure has two or more annular elastic portions arranged in multiple rings along the lower end of the water stop wall. An abutting step of bringing the waterstop structure into contact with a footing of the underwater structure; a pressing step of pressing the two or more annular elastic portions against the footing; and the two or more annular elastic portions in a pressed state A temporary closing method characterized by having an injection step of injecting a filler between the annular elastic portions.

  Thus, the temporary closing method according to the first aspect of the present invention is such that the water blocking wall is pressed by pressing the two or more annular elastic portions arranged in multiple rings along the lower end of the water blocking wall against the footing. Since the water is stopped between the lower end and the footing, there is no need to perform underwater concrete placement and the like, and the diving work process, which has a large work load and causes a long construction period, can be greatly reduced. Moreover, water stop between the lower end of a water stop wall and a footing can be performed more reliably by making a water stop structure into the multiple ring water stop structure which has two or more cyclic | annular elastic parts.

  Furthermore, since the filler is injected between the annular elastic portions of the two or more annular elastic portions, the water stop between the lower end of the water stop wall and the footing can be further strengthened. Here, the filler is a liquid or paste material that can be injected through a pipe or the like, and is solidified into a rubber shape by reacting with water or the like. That is, since the filler after injection is solidified in a rubber shape in the shape of the unevenness of the footing surface between the annular elastic portions, it exhibits a water stopping effect integrally with the annular elastic portion, and has an extremely high water stopping effect. can get. Note that the two or more annular elastic portions may be integrally configured with one elastic body, or each of the two or more annular elastic portions may be configured with a separate annular elastic body.

  Therefore, according to the temporary closing method described in the first aspect of the present invention, it is a multi-ring water stop structure having two or more annular elastic portions, and the two or more annular elastic portions are annular. By injecting the filler between the elastic parts, the water stop between the lower end of the water stop wall and the footing can be performed more reliably and firmly, so that it is possible to realize a temporary closing method with a deep applied water depth. The effect is obtained.

  In addition, there is no need to perform underwater concrete placement, etc., and the work load is large, which can greatly reduce the diving work process that causes the construction period to be prolonged. The effect of being able to shorten is obtained.

A second aspect of the present invention is the temporary closing method according to the first aspect described above, wherein the pressing step applies a downward pressing force to the upper end of the water blocking wall to cause the two or more annular shapes. A temporary closing method characterized by pressing an elastic portion against the footing.
Since the upper end of the water blocking wall is on the water surface, a downward pressing force is applied to the upper end of the water blocking wall in this way, and the annular elastic part arranged at the lower end of the water blocking wall is pressed against the footing. By stopping the water in the water blocking wall, anchor installation work or the like to the footing in water becomes unnecessary. Accordingly, it is possible to reduce the submerged work process in water with a large work load, and thus the burden on the operator can be further reduced.

According to a third aspect of the present invention, in the temporary closing method according to the first aspect described above, the pressing step includes a step of installing a retrofit anchor bolt on the footing, and the water stop structure with the postfix anchor bolt. And a step of pressing the two or more annular elastic portions against the footing.
In this way, the annular elastic portion can be pressed against the footing by fixing the water stop structure to the footing with a retrofitting anchor bolt applied to the footing.

  According to a fourth aspect of the present invention, in the temporary closing method according to any one of the first to third aspects, the injection step is performed between the annular elastic portions of the two or more annular elastic portions in a pressed state. It is a temporary closing method characterized by having a step of replacing certain water with a filler.

  In a state where two or more annular elastic portions are pressed against the footing, water is present in a substantially sealed space between the annular elastic portions, so that there is a possibility that the filling material cannot be injected smoothly as it is. Therefore, the filler is injected into the space between the annular elastic portions by replacing the filler between the annular elastic portions of the two or more annular elastic portions while discharging the water to the outside. Thereby, a smoother and more reliable filling of the filler is possible.

According to a fifth aspect of the present invention, there is provided the temporary closing method in the temporary closing method in which an underwater structure is surrounded by a temporary closing structure, and then the temporary closing structure is drained to form a work space around the underwater structure. A water stop structure provided at a lower end of a water stop wall of a cutoff structure, wherein the two or more annular elastic portions are arranged in multiple rings along the lower end of the water stop wall, and the two or more annular elastic portions. The water-stopping structure is provided with a filler injection hole capable of injecting a filler between the annular elastic portions of the two or more annular elastic portions in a state where is pressed against the footing.
According to the water stop structure according to the fifth aspect of the present invention, after the underwater structure is surrounded by the temporary closing structure, the temporary closing structure is drained to form a work space around the underwater structure. In the temporary closing method, the same effect as the invention described in the first aspect can be obtained by providing the water stopping structure at the lower end of the water stopping wall of the temporary closing structure.

According to a sixth aspect of the present invention, in the waterstop structure according to the fifth aspect described above, in the state where the two or more annular elastic portions are pressed against the footing, the annular elasticity of the two or more annular elastic portions. It is a water stop structure characterized by having a water discharge hole capable of discharging water between the parts.
According to the water stop structure according to the sixth aspect of the present invention, after the underwater structure is surrounded by the temporary closing structure, the temporary closing structure is drained to form a work space around the underwater structure. In the temporary closing method, the same effect as the invention described in the fourth aspect described above can be obtained by providing the water stopping structure at the lower end of the water stopping wall of the temporary closing structure.

  According to a seventh aspect of the present invention, in the waterstop structure according to the sixth aspect described above, a space between the annular elastic portions of the two or more annular elastic portions is partitioned into a plurality of spaces adjacent in the circumferential direction. The water stop structure is characterized in that the filler injection hole and the water discharge hole are provided for each partitioned space.

  In the two or more annular elastic portions arranged in multiple rings along the lower end of the water blocking wall, the space between the annular elastic portion and the annular elastic portion is a series of annular spaces along the lower end of the water stopping wall. Become. That is, the space between the annular elastic portion and the annular elastic portion is an annular space having a substantially same circumferential length as the circumferential length of the water blocking wall. Therefore, if the work of injecting the filler into the space between the annular elastic portions is performed only with one filler injection hole and the water discharge hole, depending on the circumferential length of the water blocking wall, the unfilled portion of the filler may be There is a risk that it will occur or the filler will solidify before it is completely filled.

  In the waterstop structure according to the seventh aspect of the present invention, the space between the annular elastic portions is partitioned into a plurality of spaces, and a filler injection hole and a water discharge hole are provided for each partitioned space. Therefore, the operation of injecting the filler into the space between the annular elastic portions by replacing the filler while discharging the water between the annular elastic portions to the outside can be performed for each partitioned space. Therefore, if the space between the annular elastic portions is partitioned with an appropriate length according to the volume of the space between the annular elastic portions and the fluidity and solidification characteristics of the filler, an unfilled portion of the filler may occur. It is possible to reliably prevent the filler from solidifying before the filler is completely filled.

  Thereby, according to the water stop structure as described in the 7th aspect of this invention, the effect that the filling operation | work of a filler can be performed reliably is acquired. Moreover, since the filling operation | work of a filler can be performed for every divided space, the filling operation | work of each space can also be performed simultaneously. Therefore, the effect that the working time of the filling operation of the filler can be shortened is also obtained.

  According to an eighth aspect of the present invention, in the waterstop structure according to any one of the fifth to seventh aspects described above, the two or more annular elastic portions are formed of an open cell body having elasticity. This is a water stop structure characterized by that.

  By bringing the waterstop structure into contact with the footing of the underwater structure and pressing the annular elastic portion of the waterstop structure against the footing, the annular elastic portion is elastically deformed flexibly along the unevenness of the footing surface. A gap between the water blocking wall and the footing is blocked by this elastically deformed annular elastic portion to stop the water. However, the annular elastic portion formed of an elastic body is deformed so as to be crushed by water pressure in water. When the annular elastic portion is deformed so as to be crushed by water pressure, depending on the degree, when the annular elastic portion is pressed against the footing, the deformation of the annular elastic portion is sufficiently caused by unevenness of the footing surface. There is a possibility that the desired water stop effect cannot be obtained due to the failure to follow, thereby causing a water leak or the like in the water stop wall after dry-up.

  In order to reduce such a fear, the water stop structure according to the eighth aspect of the present invention is formed of an open cell body in which the annular elastic portion has elasticity. In the open cell body, there are bubbles inside and the bubbles are connected to each other, so that liquid or gas can pass through. Therefore, by forming the annular elastic portion with an open cell body having such properties, the annular elastic portion is prevented from being crushed by water pressure when the annular elastic portion is pressed against the footing in water. can do. As a result, it is possible to reduce the possibility of water leakage or the like in the water blocking wall after dry-up.

  According to a ninth aspect of the present invention, in the waterstop structure according to the eighth aspect described above, the two or more annular elastic portions are provided with a sealing material having elasticity on a part of the surface thereof. It is a water stop structure characterized by

  As described above, in the open cell body, the internal bubbles are connected to each other so that liquid or gas can pass through. Therefore, depending on the water pressure around the water stop structure and other environmental conditions, a small amount of water may leak in the water stop wall through the bubbles of the annular elastic part after dry-up. In order to prevent such a small amount of water leakage, the water stop structure according to the ninth aspect of the present invention is provided with a sealing material having elasticity on a part of the surface of the annular elastic portion.

  Here, the sealing material having elasticity means an elastic material that does not allow water to pass through, such as a rubber-based adhesive or a caulking material having elasticity. With this sealing material, it is possible to reduce the possibility of water entering the water blocking wall through bubbles inside the annular elastic portion formed of open cells after dry-up. Moreover, since the sealing material has elasticity, the elastic deformation of the annular elastic portion is not hindered.

  Since the seal material is provided on a part of the surface of the annular elastic portion formed of the open cell body, the state in which water can enter the bubbles inside the open cell body is maintained. The Therefore, when the annular elastic portion is pressed against the footing in water, the annular elastic portion is not crushed by water pressure.

According to a tenth aspect of the present invention, in the water stop structure according to any one of the fifth to ninth aspects described above, the two or more annular elastic portions are integrally formed of a single elastic body. This is a water stop structure characterized by that.
In this way, since the two or more annular elastic portions arranged in a multiple annular shape along the lower end of the water blocking wall are formed of one elastic body, the number of parts and the manufacturing process of the water blocking structure are reduced. be able to. Thereby, the effect that the water stop structure which concerns on this invention can be manufactured at low cost is acquired.

  An eleventh aspect of the present invention is the temporary closing structure provided with the water stop structure according to any one of the fifth to tenth aspects described above, wherein the two or more from the upper end of the water stop wall. A temporary closing structure comprising a filler injection path capable of injecting a filler between the annular elastic portions of the annular elastic portion.

  According to the temporary closing structure according to the eleventh aspect of the present invention, after the underwater structure is surrounded by the temporary closing structure, the temporary closing structure is drained to form a work space around the underwater structure. In the temporary closing method, the same effects as those of the first aspect described above can be obtained. In addition, since the upper end of the water blocking wall is on the water surface, the work of injecting the filler between the annular elastic portions of the two or more annular elastic portions can be performed from the water surface. The effect that it can be reduced is obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<First embodiment>
First, a first embodiment of the “temporary closing method” according to the present invention will be described with reference to FIGS.
FIG. 1 is a front view of a main part of a temporary closing structure 10 according to the present invention.

  An existing T-type pier 52 (hereinafter simply referred to as pier 52) as an “underwater structure” is installed on a footing 51 constructed on a bottom ground 50 such as a river or the sea. 54 is supported. A construction method used when performing maintenance, inspection, repair or seismic reinforcement work on such a pier 52 is a “temporary closing method”. In this “temporary closing method”, the pier 52 is surrounded by the temporary closing structure 10 as shown in the figure, and then the interior of the temporary closing structure 10 is drained to form a work space around the pier 52. This is a method of performing maintenance, inspection, repair or seismic reinforcement work for the pier 52. In addition, the code | symbol W is the position of water surfaces, such as a river, and the code | symbol Y is the direction of water flows, such as a river.

  The temporary closing structure 10 according to the present invention has a water blocking wall 11 that forms a work space around the pier 52. At the lower end of the water stop wall 11, a water stop structure 30 is provided for stopping the contact surface with the footing 51. The cross beam 12 is for positioning in the vicinity of the upper end of the water blocking wall 11 so that the position of the temporary closing structure 10 after installation with respect to the pier 52 is not displaced by a water flow or the like.

  In the “temporary closing method” according to the present invention, first, the ground 50 on the upper surface portion of the footing 51 is crushed by a known pump dredger or the like (not shown), and the footing 51 serving as the installation base surface of the temporary closing structure 10. Expose the top surface of. Subsequently, a plurality of brackets 21 are disposed around the leg head (portion above the water surface W of the pier 52) as shown in the figure. Subsequently, the temporary closing structure 10 is set so as to surround the pier 52, and the water stop structure 30 disposed at the lower end of the water stop wall 11 is brought into contact with the footing 51 (contact process). The water blocking wall 11 is equally divided (for example, divided into four equal parts) into a plurality of water blocking wall segments (not shown) in the circumferential direction. The water blocking wall 11 can be configured to surround the periphery of the pier 52 by arranging and connecting the water blocking wall segments around the pier 52.

  And by pushing down the upper end of the water stop wall 11 with the jack 22 arrange | positioned at the bracket 21, the water stop structure 30 is pressed on the fixing surface of the footing 51, and, thereby, the inside of the water stop wall 11 is carried out. Stop water (pressing process). Since the upper end of the water stop wall 11 is above the water surface W, pressing the upper end of the water stop wall 11 presses the water stop structure 30 against the fixing surface of the footing 51 to stop the inside of the water stop wall 11. By doing so, the water stop work can be performed above the water surface W. That is, the anchor installation work etc. to the footing 51 in water become unnecessary. Accordingly, it is possible to reduce the submerged work process in water with a large work load, and thus the burden on the operator can be further reduced.

FIG. 2 is a plan view of an essential part illustrating the water stop structure 30 according to the present invention.
The water stop structure 30 according to the present invention includes the first annular elastic body 32 and the first annular elastic body 32 as “two or more annular elastic portions arranged in multiple rings” along the lower end of the water stop wall 11. It has a double ring water stop structure provided with a second annular elastic body 33 disposed on the outside (FIG. 2A). The outlet of the injection tube 14 at the lower end of the water blocking wall 11 is provided between the first annular elastic body 32 and the second annular elastic body 33 (FIG. 2A). The first annular elastic body 32 and the second annular elastic body 33 are waterproof seals formed by annularly forming an elastic body such as a rubber material or a sponge material, and are pressed by the fixing surface of the footing 51 (pressing Step), while being deformed flexibly so as to be crushed, it closely adheres to the fixing surface, and its inside is sealed. Moreover, the 1st annular elastic body 32 and the 2nd annular elastic body 33 are divided | segmented into plurality according to the division | segmentation of the water blocking wall 11, The seam part is shown in FIG.2 (b) and FIG.2 (c). As shown in the drawing, the convex portion on the other end side is fitted and joined to the concave portion on the one end side.

  In this way, the water stop structure 30 composed of the elastic bodies (the first annular elastic body 32 and the second annular elastic body 33) is pressed against the fixing surface of the footing 51 to fix the bottom end of the water blocking wall 11 and the footing 51. Since the water is stopped between the surfaces, there is no need to perform underwater concrete placement and the like, and the diving work process, which has a large work load and causes a long construction period, can be greatly reduced. Therefore, it is possible to reduce the work burden on the operator and shorten the construction period. Further, the water stop structure 30 has a double ring water stop structure composed of the first annular elastic body 32 and the second annular elastic body 33, so that the space between the lower end of the water stop wall 11 and the fixing surface of the footing 51 is reduced. The water can be stopped more reliably. Examples of the rubber material and sponge material include natural rubber, urethane rubber, isoprene rubber, chlorobrene rubber, and the like.

FIG. 3 is a front view illustrating an injection process in which a filler is injected between the first annular elastic body 32 and the second annular elastic body 33 in a pressed state. FIG. 4 is an enlarged front view of a part of the water stop structure 30 according to the present invention.
As shown in FIG. 4, the water stop structure 30 is provided with a first annular elastic body 32 and a second annular elastic body 33 bolted to a support frame 31 provided at the lower end of the water stop wall 11. It has the structure which was made. The first annular elastic body 32 and the second annular elastic body 33 in a state of being pressed against the fixing surface of the footing 51 are deformed flexibly so that the lower ends are crushed as shown in the drawing, and are in close contact with the fixing surface of the footing 51. In addition, an injection pipe 14 that communicates from the upper end to the lower end of the water blocking wall 11 is provided inside the water blocking wall 11. The injection pipe 14 is connected to a filler injection hole 35 provided in the water stop structure 30. The filler injection hole 35 is a hole that communicates with the space 34 between the first annular elastic body 32 and the second annular elastic body 33.

  In a state where the water stop structure 30 is pressed against the fixing surface of the footing 51, the cut beam 12 is installed between the uppermost inner peripheral surface of the water stop wall 11 and the bridge pier 52, and the temporary closing after the installation to the pier 52 is performed. The structure 10 is positioned so that the position of the structure 10 is not displaced by a water flow or the like (FIG. 3). From this state, as indicated by symbol A, the first annular elastic body 32 and the first annular elastic body 32 of the water stop structure 30 on the lower end side of the water stop wall 11 from the upper end side of the water stop wall 11 through the injection pipe 14. A filler is injected into the space 34 between the two annular elastic bodies 33 (injection step).

  Here, the filler is a liquid or paste material that can be injected through a pipe or the like, and is solidified into a rubber shape by reacting with water or the like. Since the filler after injection is solidified into a rubber shape in a shape along the irregularities of the surface of the footing 51 in the space 34 between the first annular elastic body 32 and the second annular elastic body 33, the first annular elastic body The water stop effect is exhibited integrally with the body 32 and the second annular elastic body 33, and an extremely high water stop effect is obtained. Thereby, the water stop between the lower end of the water stop wall 11 and the fixing surface of the footing 51 can be performed more reliably and firmly, so that a temporary closing method with a deep applicable water depth can be realized.

  In addition, since water exists in the sealed space 34 between the first annular elastic body 32 and the second annular elastic body 33 during the injection process, the filling material can be injected smoothly as it is. There is no possibility. Therefore, the water between the first annular elastic body 32 and the second annular elastic body 33 is replaced with the filler while being discharged to the outside through the water discharge pipe 13 from the water discharge hole 36 communicating with the space 34. Thus, the filler is injected into the space 34 between the first annular elastic body 32 and the second annular elastic body 33. Thereby, a smoother and more reliable filling of the filler is possible.

  More specifically, by injecting the filler through the injection tube 14, water between the first annular elastic body 32 and the second annular elastic body 33 is pushed out from the water discharge hole 36. It is discharged to the outside through the water discharge pipe 13. Then, when the filler is discharged from the water discharge pipe 13, the filler is completely filled between the first annular elastic body 32 and the second annular elastic body 33. Can be confirmed. The water in the space 34 may be discharged using a part of the plurality of injection pipes 14 without providing the dedicated water discharge pipe 13.

FIG. 5 is a front view illustrating a dry-up process in the water blocking wall 11.
After injecting a filler into the space 34 between the first annular elastic body 32 and the second annular elastic body 33 of the water stop structure 30, the inside of the water stop wall 11 is drained (symbol B) and dried up. Thereby, a work space can be formed around the pier 52 in the water blocking wall 11.

<Second embodiment>
Next, a second embodiment of the “temporary closing method” according to the present invention will be described with reference to FIG.
FIG. 6 is an enlarged front view of a part of the water stop structure 30 in the second embodiment of the “temporary closing method” according to the present invention.

  Since the second embodiment of the “temporary closing method” according to the present invention is the same as the first embodiment except that the pressing process is different, the description of the common processes is omitted. In the pressing process in the second embodiment, instead of pressing the upper end of the water blocking wall 11 by the jack 22 in the first embodiment (FIG. 1), the post-installation anchor bolt 37 is applied to the footing 51, and the post-installation anchor bolt 37 is used. By fixing the water stop structure 30 to the footing 51, the first annular elastic body 32 and the second annular elastic body 33 are pressed against the fixing surface of the footing 51. Although there is a work process due to diving work, there is no need to install a pressing means such as the jack 22 on the upper end of the water blocking wall 11, so even if the pressing means such as the jack 22 cannot be installed due to some restrictions, the present invention is concerned. There is an advantage that the “provisional deadline method” can be used.

<Third embodiment>
Next, a third embodiment of the “temporary closing method” according to the present invention will be described with reference to FIG.
FIG. 7 is an enlarged front view of a part of the water stop structure 30 in the third embodiment of the “temporary closing method” according to the present invention.

  Since the third embodiment of the “temporary closing method” according to the present invention is the same as the first embodiment except that the structure of the water stop structure 30 is different, the description of the common steps is omitted. The water stop structure 30 in the third embodiment is different from the first embodiment in that the configuration of the second annular elastic body 33 is different. More specifically, the second annular elastic body 33 in the third embodiment is made of a thin plate-like elastic body as shown in the figure, and the thin plate-like elastic body is provided around the outer peripheral surface near the lower end of the water blocking wall 11. Has been configured. Moreover, the 2nd cyclic | annular elastic body 33 is divided | segmented into plurality according to the division | segmentation of the water blocking wall 11, and it joins so that it may overlap in the seam part.

  The water stop structure 30 in the first embodiment is suitable when the water pressure acting on the water stop structure 30 is relatively high, such as a river having a water depth of 5 m or more. On the other hand, since the water stop structure 30 in the third embodiment has a simpler configuration, the water depth is relatively shallow, such as a river having a water depth of less than 5 m, and acts on the water stop structure 30. Suitable when the water pressure is relatively low. And there exists a merit that construction cost can be reduced by the part which is a simpler structure.

<Fourth embodiment>
Next, a fourth embodiment of the “temporary closing method” according to the present invention will be described with reference to FIGS. 8 and 9.
FIG. 8 is an enlarged front view of a part of the water stop structure 30 in the fourth embodiment of the “temporary closing method” according to the present invention. FIG. 9 is a plan view illustrating the water stop structure 30 in the fourth embodiment from the bottom side.
Since the fourth embodiment of the “temporary closing method” according to the present invention is the same as the first embodiment except that the structure of the water stop structure 30 is different, the description of the common steps is omitted. The water stop structure 30 in the fourth embodiment includes a first elastic annular portion 381 and a second elastic annular portion 382 as “two or more annular elastic portions arranged in multiple rings” along the lower end of the water blocking wall 11. Is formed integrally with the annular elastic body 38. That is, the elastic body 38 corresponds to the first elastic annular body 32 and the second annular elastic body 33 in the first embodiment formed integrally with one elastic body. Thus, by integrally forming “two or more annular elastic portions arranged in multiple rings” with one elastic body 38, the number of parts and the manufacturing process of the water stop structure 30 can be reduced. . Thereby, the water stop structure 30 according to the present invention can be manufactured at a lower cost.

  In the fourth embodiment, the annular space formed between the first elastic annular portion 381 and the second elastic annular portion 382 is partitioned into a plurality of spaces 34 adjacent in the circumferential direction by the partition portion 341. Each of the partitioned spaces 34 is provided with a filler injection hole 35 and a water discharge hole 36 (FIG. 9). Accordingly, the water stop structure 30 in the fourth embodiment replaces the filler while discharging the water between the first elastic annular portion 381 and the second elastic annular portion 382 to the outside, and the first elastic annular portion 30 The operation of injecting the filler into the space between the portion 381 and the second elastic annular portion 382 can be performed for each partitioned space 34. The length of each space 34 is set so as to be a volume that allows the filling of each space 34 and the discharge of water from each space 34 to be completed before the filler is solidified. More specifically, the length of each space 34 depends on the volume of the annular space formed between the first elastic annular portion 381 and the second elastic annular portion 382 and the fluidity and solidification characteristics of the filler. What is necessary is just to determine suitably.

  As a result, it is possible to reliably prevent an unfilled portion of the filler from occurring or the filler to solidify before the filler is completely filled. Therefore, the filling operation of the filler can be reliably performed. In addition, since the filling work of the filler in each space 34 can be performed simultaneously in parallel, the work time of the filling work of the filling material can be shortened.

  As described above, the water blocking wall 11 is equally divided into a plurality of water blocking wall segments (not shown) in the circumferential direction for convenience of installation so as to surround the periphery of the pier 52 (for example, divided into four equal parts). Has been. And the water blocking wall 11 can be comprised so that the circumference | surroundings of the pier 52 may be enclosed by arrange | positioning and connecting each water blocking wall segment to the circumference | surroundings of the pier 52 now. Therefore, in the water stop structure 30, the elastic body 38 is divided into a plurality of elastic body segments 38 a, 38 b... In the circumferential direction at the dividing portion 39 according to the division of the water stop wall 11. Each of the water blocking wall segments of the water blocking wall 11 is disposed. Hereinafter, the elastic body segment 38a and the elastic body segment 38b will be described as an example.

  As shown in the figure, the dividing portion 39 is provided at an intermediate position of the partitioned space 34 (FIG. 9). In a state where the water blocking wall 11 is configured so as to connect the water blocking wall segments so as to surround the periphery of the pier 52, the joint portions (divided portions 39) of the elastic body segments 38a and 38b each have a cross-sectional surface. It will be in the state which contacted and contacted. Then, after the first elastic annular portion 381 and the second elastic annular portion 382 are pressed against the fixing surface of the footing 51 (pressing step), when a filler is injected into each space 34 (injecting step), the elastic body segment 38a and the elastic body 38a are elastic. The filler enters and solidifies even in a slight gap in the joint portion (divided portion 39) with the body segment 38b, and the slight gap is closed.

  That is, the filler injected into the space 34 plays a role of improving the water stop effect at the contact surface between the first elastic annular portion 381 and the second elastic annular portion 382 and the fixing surface of the footing 51, and the first It also serves to stop water at the joint portion (divided portion 39) between the elastic body segment 38a and the elastic body segment 38b constituting the elastic annular portion 381 and the second elastic annular portion 382. Accordingly, it is possible to reduce the possibility of water leakage or the like in the water blocking wall 11 at the joint portion (divided portion 39) between the elastic body segment 38a and the elastic body segment 38b after dry-up.

  Furthermore, the water stop structure 30 in the fourth embodiment is formed of a sponge material made of an open cell body in which the elastic body 38 has elasticity. Examples of the sponge material made of open cells include those made of thermoplastic polyurethane, polyethylene and the like. Hereinafter, the technical significance of the elastic body 38 formed of a sponge material made of an open cell body will be described with reference to FIGS. 10 and 11 as well.

FIG. 10 schematically shows and contrasts an elastic body 38 made of closed cells and an elastic body 38 made of open cells.
The elastic body 38 (FIG. 10A) made of closed cells has bubbles C therein, but the bubbles C are not connected to each other. That is, the bubbles C are partitioned by the wall. Accordingly, water is not sucked in the water, and generally, gas such as air exists in the bubbles C.

  As shown in FIG. 10B, the elastic body 38 made of such closed cells is in a state in which the internal bubbles C are compressed and crushed by water pressure, thereby causing shape deformation. At the same time, the apparent density becomes higher and harder. That is, when the first elastic annular portion 381 and the second elastic annular portion 382 are pressed against the footing 51, the first elastic annular portion 381 is hardened in a state of being crushed by the shape deformation caused by water pressure. The deformation of the portion 381 and the second elastic annular portion 382 cannot sufficiently follow, and there is a possibility that a desired water stop effect cannot be obtained, and there is a possibility that water leakage or the like may occur in the water stop wall 11 after dry-up. There is.

  On the other hand, the elastic body 38 (FIG. 10 (c)) according to the present invention, which is composed of open cells, similarly has bubbles C therein, but small holes (not shown) in the walls between the bubbles C. Is open, the bubbles C are connected to each other. Accordingly, in water, as indicated by the symbol D, water can be sucked into the internal bubbles C and the water can pass through the bubbles C.

  Since the elastic body 38 according to the present invention composed of such an open cell body allows water to pass through the inside thereof, the first elastic annular portion 381 and the second elastic annular portion are pressed when pressed against the footing 51 in water. It is possible to prevent 382 from being crushed by water pressure. That is, the elastic body 38 according to the present invention, which is formed of an open cell body, hardly becomes hard due to a shape deformation due to water pressure or an apparent density. Accordingly, the elastic body 38 according to the present invention, which is an open cell body, is in a state of being crushed by water pressure when the first elastic annular portion 381 and the second elastic annular portion 382 are pressed against the footing 51. 51, the deformation of the first elastic annular portion 381 and the second elastic annular portion 382 cannot sufficiently follow the irregularities on the surface of the surface 51, and a desired water-stopping effect cannot be obtained. It is possible to prevent leaks and the like from occurring.

FIG. 11 schematically illustrates a state where the elastic body 38 according to the present invention, which is an open cell body, is pressed and compressed.
In the water, the elastic body 38 according to the present invention, which is formed of an open cell body, allows water to pass through the bubble C as shown by the symbol D ((a) in FIG. 11). When the elastic body 38 is pressed against the footing 51 and the elastic body 38 made of an open cell body is compressed and deformed, the bubble C is compressed and crushed as shown in FIG. Therefore, it becomes difficult for water to pass through. And in the state which carried out compression deformation to the state where the bubble C hardly exists, since the bubble C which allows water to pass through collapses and hardly exists, it will be in the state which hardly passes water and will exhibit a water stop effect. Therefore, even if the elastic body 38 is formed of an open cell body, there is almost no risk of water leaking through the bubbles C in the water blocking wall 11 after dry-up.

  Furthermore, the water stop structure 30 in the fourth embodiment is provided with a sealing material 40 on the outer peripheral surface of the second elastic annular portion 382 facing the underwater side (FIG. 8). The sealing material 40 is formed of an elastic material that does not allow water to pass through. For example, the outer peripheral surface of the second elastic annular portion 382 may be coated with a rubber adhesive or an elastic caulking material. With this sealing material 40, it is possible to reduce the possibility of water entering the water blocking wall 11 through the bubbles inside the second elastic annular portion 382 formed of a sponge material made of open cells after dry-up.

  Moreover, the sealing material 40 has elasticity. Accordingly, it is possible to further reduce the possibility of water leakage in the water blocking wall 11 after dry-up without hindering elastic deformation of the second elastic annular portion 382. Since the sealing material 40 is provided only on the outer peripheral surface of the second elastic annular portion 382, when the first elastic annular portion 381 and the second elastic annular portion 382 are pressed against the footing 51, The state in which water can enter the bubbles inside the elastic annular portion 382 is maintained. Therefore, when the first elastic annular portion 381 and the second elastic annular portion 382 are pressed against the footing 51, the second elastic annular portion 382 is not crushed by water pressure.

  The sealing material 40 may be provided on the inner peripheral surface of the first elastic annular portion 381, or may be provided on both the inner peripheral surface of the first elastic annular portion 381 and the outer peripheral surface of the second elastic annular portion 382. good. Moreover, it is also possible to form the first annular elastic body 32 and the second annular elastic body 33 in the first to third embodiments with a sponge material made of an open cell body, and a seal material on a part of the surface thereof. Needless to say, 40 can be provided, and the above-described effects can be obtained. The elastic body 38 is preferably formed of a sponge material or the like made of open cell as described above. However, the present invention can be implemented even if formed of a rubber material or a sponge material or the like made of closed cell. is there.

<Fifth embodiment>
Next, a fifth embodiment of the “temporary closing method” according to the present invention will be described with reference to FIG.
Since the fifth embodiment of the “temporary closing method” according to the present invention is the same as the first embodiment except that the structure of the water stop structure 30 is different, the description of the common steps is omitted. The water stop structure 30 in the fifth embodiment includes a first elastic annular portion 381 and a second elastic annular portion 382 as “two or more annular elastic portions arranged in multiple rings” along the lower end of the water blocking wall 11. The third elastic annular portion 383 is integrally formed with the annular elastic body 38. That is, the water stop structure 30 in the fifth embodiment is a double ring structure water stop structure 30 in the fourth embodiment having a triple ring structure.

  Therefore, in the fifth embodiment, the space 34 between the first annular elastic portion 381 and the second annular elastic portion 382 and the space 34 between the second annular elastic portion 382 and the third annular elastic portion 383 are respectively provided. The filler will be filled. Thus, since it becomes possible to stop water still more firmly by making the water stop structure 30 into a triple ring structure, it is effective especially when constructing the temporary closing structure 10 in a deep water location. is there. Furthermore, as another embodiment, the water stop structure 30 can be a quadruple ring structure or a pentacycle structure.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say.

It is a principal part front view of the temporary closing structure which concerns on this invention. It is a principal part top view which illustrated the water stop structure which concerns on this invention. It is the front view which illustrated the injection | pouring process which inject | pours a filler. It is the front view which expanded and illustrated a part of water stop structure concerning the present invention. It is the front view which illustrated the dry-up process in a water stop wall. It is the front view which expanded and illustrated a part of water stop structure in 2nd Example. It is the front view which expanded and illustrated a part of water stop structure in 3rd Example. It is the front view which expanded and illustrated a part of water stop structure in 4th Example. It is the top view which illustrated the water stop structure in 4th Example from the bottom face side. A closed cell and an open cell are schematically illustrated and contrasted. The state which pressed and compressed the open-cell body is typically illustrated. It is the front view which expanded and illustrated a part of water stop structure in 5th Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Temporary cutoff structure, 11 Water stop wall, 13 Water discharge pipe, 14 Injection pipe, 21 Bracket, 22 Jack, 30 Water stop structure, 32 1st ring elastic body, 33 2nd ring elastic body, 35 Filler injection Hole, 36 Water discharge hole, 38 Elastic body, 40 Sealing material, 50 Ground, 51 Footing, 52 Bridge pier, 381-383 First to third annular elastic part, W water surface, Y Water flow direction

Claims (11)

After the underwater structure is surrounded by the temporary deadline structure, the temporary deadline structure is drained to form a work space around the underwater structure,
The water stop structure provided at the lower end of the water stop wall of the temporary closing structure includes two or more annular elastic portions arranged in multiple rings along the lower end of the water stop wall,
A contact step of bringing the water stop structure into contact with the footing of the underwater structure;
A pressing step of pressing the two or more annular elastic portions against the footing;
A temporary closing method characterized by comprising an injection step of injecting a filler between the annular elastic portions of the two or more annular elastic portions in a pressed state.   2. The temporary closing method according to claim 1, wherein in the pressing step, a downward pressing force is applied to an upper end of the water blocking wall to press the two or more annular elastic portions against the footing. Temporary deadline construction method.   2. The temporary closing method according to claim 1, wherein the pressing step includes a step of installing a retrofitting anchor bolt on the footing, and fixing the water stop structure to the footing with the retrofitting anchor bolt, and the two or more annular rings. And a step of pressing an elastic part against the footing.   The temporary closing method according to any one of claims 1 to 3, wherein the injection step includes a step of replacing water between the annular elastic portions of the two or more annular elastic portions in a pressed state with a filler. A temporary deadline construction method characterized by that. After the underwater structure is surrounded by the temporary closing structure, the lower end of the water stop wall of the temporary closing structure in the temporary closing method in which the temporary closing structure is drained to form a work space around the underwater structure. A water stop structure provided in
Two or more annular elastic portions arranged in a multiple annular shape along the lower end of the water blocking wall;
And a filler injection hole capable of injecting a filler between the annular elastic portions of the two or more annular elastic portions in a state where the two or more annular elastic portions are pressed against the footing. Water structure.   The water stop structure according to claim 5, wherein water that can drain water between the two or more annular elastic portions in a state where the two or more annular elastic portions are pressed against the footing. A water-stop structure having a discharge hole.   The water stop structure according to claim 6, wherein a space between the annular elastic portions of the two or more annular elastic portions is partitioned into a plurality of spaces adjacent in the circumferential direction, and the filling is performed for each partitioned space. A water-stop structure having a material injection hole and the water discharge hole.   The water stop structure according to any one of claims 5 to 7, wherein the two or more annular elastic portions are formed of an open cell body having elasticity.   The water stop structure according to claim 8, wherein the two or more annular elastic portions are provided with a sealing material having elasticity on a part of a surface thereof.   The water stop structure according to any one of claims 5 to 9, wherein the two or more annular elastic portions are integrally formed of one elastic body.   It is the said temporary closing structure provided with the water stop structure of any one of Claims 5-10, Comprising: It fills between the annular elastic parts of the said 2 or more annular elastic part from the upper end of the said water stop wall. A temporary closing structure characterized by comprising a filler injection path through which a material can be injected.

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