JP5307372B2 - Construction method of revetment retaining wall and shade concrete block and bottom formwork used for it - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a method for constructing a revetment retaining wall constructed by covering a cap concrete block on a sheet pile, and a cap concrete block and a bottom mold used therefor.

  A revetment retaining wall constructed by covering a sheet pile with a shaded concrete block is constructed by pouring the cast concrete between the side plate of the shaded concrete block and the side face of the sheet pile. Normally, a bottom plate is provided on the cap concrete block so that the cast concrete does not leak downward, and the edge of the bottom plate abuts against the side of the sheet pile, but in fact the edge of the bottom plate and the side of the sheet pile are in close contact. There was a gap. This is because it is difficult for the sheet pile to stand as designed, and the sheet piles are inevitably tilted. From now on, the bottom plate will be omitted, and a bottom mold will be used to block the space between the side of the cap concrete block and the side of the sheet pile from below, or the gap between the edge of the bottom plate and the side of the sheet pile will be provided on the cap concrete block. For example, a packing material member is used (Patent Document 1).

  Patent Document 1 proposes a method in which the bottom plate (bottom plate material) that matches the shape of the steel sheet pile on the water channel side is fixed to the bottom of the shade concrete block (the shade block main body) with a giant clam vise, omitting the bottom plate. (Patent Document 1 [Claim 1], [FIG. 1] and [FIG. 2]). This eliminates the need for a square member that supports the bottom mold frame used before disclosing the method of Patent Document 1, and eliminates the need for fixing the square member fixing pin and the bottom plate fixing pin by welding or the like. The construction work is extremely simplified (Patent Document 1, paragraph [0027]). Patent Document 1 proposes a method of providing a packing material on the front edge (protruding end) following the sheet pile of the bottom plate (protruding bottom) of the cap concrete block (Patent Document 1 [Claim 2], [Fig. 3] and [FIG. 4]). As a result, the bottom plate is provided integrally with the cap concrete block, and the packing material is provided at the front edge of the bottom plate, so that the advantage that the bottom mold form separate from the cap concrete block is unnecessary is obtained (patent) Literature 1 paragraph [0027]).

JP 09-003850 A

  The method using the bottom mold form disclosed in Patent Document 1 is preferable because it can reliably block the bottom of the concrete block. However, it is not easy to attach the bottom mold frame to the shade concrete block with a clam vise while keeping the front edge of the bottom mold frame in close contact with the side surface of the sheet pile. In addition, Patent Document 1 does not show whether the bottom formwork is collected after placing concrete or left as it is integrally with the shaded concrete block, but when the former collection is selected. If the bottom formwork that has been peeled off from the concrete placed as a recovery work cannot be supported well, the bottom formwork will be inadvertently dropped, resulting in danger to the operator. The problem of being submerged occurs. On the other hand, when the latter is selected, there is a problem that the cost for constructing the revetment retaining wall is increased only for the bottom mold.

  In the method using the packing material disclosed in Patent Document 1, since the size of the gap between the front edge of the bottom plate of the cap concrete block and the side face of the sheet pile is not constant, it is difficult to completely block any gap with the packing material. . In addition, a material having elasticity or flexibility is inevitably used for the packing material, but the packing material having such elasticity or flexibility cannot sufficiently support the placed concrete, and the concrete flows out. There is a risk that. Furthermore, if the packing material remains in the gap that should be filled with concrete, the portion where the packing material remains is evaluated as a cross-sectional defect, and repair work is required. In this case, it is conceivable to use a large shaded concrete block capable of placing a sufficient amount of concrete within the range excluding the cross-sectional defect, but there is a problem of an increase in cost associated with the enlargement of the shaded concrete block.

  From this, when pouring the cast concrete between the side plate of the cap concrete block and the side surface of the sheet pile, it is considered that the method using the bottom mold is preferable to the method using the packing material. In addition to considering the simplification and certainty of the installation work of the bottom formwork, and considering the cost of building a revetment retaining wall, we chose to collect the bottom formwork and Simplification and safety must also be considered. Therefore, paying attention to the installation work and the recovery work when using such a bottom formwork, the construction method of the revetment retaining wall was reviewed, and the improvement of the shaded concrete block and the bottom formwork necessary for that was examined.

  As a result of the study, what was developed is that when building a revetment retaining wall by covering a sheet pile with a cap concrete block consisting of a side plate that is lowered vertically and a bottom plate that projects from the lower edge of the side plate, A bottom formwork with buoyancy is used to pour the cast concrete between the side plate of the concrete block and the side of the sheet pile, and the bottom formwork is in close contact with the bottom of the bottom plate of the concrete block before pouring the cast concrete. After closing the gap between the front edge of the bottom plate of the cap concrete block and the side surface of the sheet pile from below with the bottom mold, and pouring concrete, the bottom mold is separated from the lower surface of the bottom plate of the cap concrete block. A method for constructing a revetment retaining wall that recovers the bottom formwork without submerging it. The present invention is directed to various conventionally known steel sheet piles, but there is no sheet pile limitation based on the construction method. The bottom mold frame has its front edge abutted against the side face of the sheet pile, and its upper surface is pressed against the front edge of the bottom plate of the cap concrete to close the gap between the front edge of the bottom plate of the cap concrete block and the side face of the sheet pile.

  The construction method of the revetment retaining wall of the present invention is characterized in that a bottom mold having buoyancy is used. This feature makes it possible to reduce the weight of the bottom mold for easy handling, and to recover the bottom mold without being submerged even if it falls into the sea. That is, according to the present invention, before pouring the cast concrete, the bottom mold is brought into close contact with the bottom surface of the bottom plate of the cap concrete block, and the gap between the front edge of the bottom plate of the cap concrete block and the side surface of the sheet pile is set to the bottom. Easy and reliable collection work to close the bottom formwork with the formwork or to separate the bottom formwork from the bottom surface of the bottom slab of the concrete block and to collect the bottom formwork without being submerged. It becomes.

Specific means for bringing the bottom mold into close contact with the bottom surface of the bottom plate of the cap concrete block is not limited to engagement between an engagement pin and a key groove as will be described later. When the bottom mold is brought into close contact with the bottom surface of the bottom plate, a part of the bottom mold is engaged with the bottom plate so that the bottom mold is brought into close contact with the bottom surface of the bottom plate, and the engagement portion between the bottom mold and the bottom plate Insert a wedge between the bottom plate bottom surface and the bottom mold frame from the side plate side that is more rearward, lift the front from the engagement part of the bottom mold frame, and press the top surface strongly against the front edge of the bottom plate of the cap concrete The concrete to be placed is prevented from leaking and the range in which the concrete to be placed adheres to the bottom mold is limited to the gap between the front edge of the bottom plate of the cap concrete block and the side face of the sheet pile. Make recovery work easier .

In the method for constructing a revetment retaining wall according to the present invention, the cap concrete block and the bottom mold are each configured exclusively. First, the cap concrete block used in the method for constructing a revetment retaining wall according to the present invention is provided with an engagement pin on the bottom plate and a fixing pin on the side plate, and the engagement pin is formed from the bottom surface of the bottom plate of the cap concrete block. In a state where the key groove of the bottom mold that is protruded and is in close contact with the bottom surface of the bottom plate is engaged, the bottom mold is restrained and moved toward and away from the side surface of the sheet pile, and the fixing pin is on the side of the cap concrete block The bottom mold is in close contact with the lower surface of the bottom plate of the cap concrete block in a state where the bottom flange protrudes from the back of the plate and the fixing flange of the bottom mold is connected. In this shaded concrete block, an engagement pin is engaged with a key groove of the bottom mold frame to support the bottom mold frame, and a fixing pin is connected to a fixing flange of the bottom mold frame to fix the position of the support frame. Then, the bottom mold is brought into close contact with the bottom plate. Since the engaging pin or the fixing pin may remain in the shaded concrete block after the bottom mold is recovered, it is preferable to configure the engaging pin or the fixing pin with a rust preventive material or perform a rust preventive treatment.

  Further, the bottom mold used in the method for constructing a revetment retaining wall according to the present invention is configured by providing a floating body with a mold frame portion, a connecting portion, and a fixing portion, and the floating body includes itself, the mold frame portion, the connecting portion, and It is a structure that generates buoyancy against the combined weight of the fixed part, and the mold part has a front edge that follows the side face of the sheet pile, and the front edge of the bottom plate of the cap concrete block and the side face of the sheet pile The connecting portion is provided on the upper surface of the floating body as a member having a plane larger than the gap with the gap, and the connecting portion is provided along the upper surface of the floating body as a member having a key groove extending in a direction in which the floating body approaches and separates on the side surface of the sheet pile With the engagement pin protruding from the bottom surface of the bottom plate of the cap concrete block engaged with the key groove, the floating body is moved toward and away from the side surface of the sheet pile while restraining the floating body, and the fixed portion is the cap concrete block Fixed flange standing on the back of the side plate As a member, the floating body is provided so as to protrude from the upper surface of the floating body, and the fixing pin protruding from the back surface of the side plate of the cap concrete block is connected to the fixing flange, and the floating body is brought into close contact with the lower surface of the bottom plate of the cap concrete block. The configuration. The formwork part, the coupling part, the fixing part and the additional reinforcing element provided on the floating body may be integrated so as not to be connected or separated, or may be freely connected and separated.

  The floating body is a structure that generates the buoyancy of the bottom mold, which is a feature of the present invention, and the configuration is not limited as long as the buoyancy can be generated. For example, a solid structure floating body made of a material such as styrene foam having a lighter specific gravity than water (seawater) or a metal plate with a higher specific gravity than water (seawater) is assembled to make the interior hollow, and the specific gravity is higher than that of water (seawater) as a whole. A floating body with a hollow structure with a lighter weight can be considered. Further, even when a metal rod having a higher specific gravity than water (seawater) is assembled, a floating body with a frame structure in which members (e.g. floats) equivalent to the solid structure or the hollow structure are attached. Good. Which one is selected may be appropriately determined according to the required size and shape of the bottom mold, attachment work, and collection work.

  The formwork part is a member that is in direct contact with the concrete to be placed and has the original function of the bottom formwork to prevent the concrete from flowing out. What is necessary is just a member which has a bigger plane than the clearance gap between the front edge of this, and the side surface of the said sheet pile. However, it is preferable that the steel plate is composed of a steel plate in order to ensure rigidity to withstand the placed concrete and to take the peeling from the placed concrete in the recovery operation. In this case, the mold part made of a steel plate is attached to the upper surface of the solid structure or the hollow structure floating body in a contact state, and is mounted across the frame of the frame structure floating body. Become.

  The connecting portion is a member having a key groove that is paired with the engaging pin of the cap concrete block. As will be described later, when the reinforcing frame is integrated with the floating body, the key frame may be provided in the reinforcing frame. Here, when the engagement pin of the cap concrete block is configured with a bolt, for example, the “key groove” of the present invention includes a front end through-hole into which the bolt head of the engagement pin is inserted, and the engagement pin from the through-hole. It means a long hole composed of a guide groove extending rearward with the width of the bolt body. The bottom mold is formed by inserting the bolt head of the engaging pin of the cap concrete block into the key groove from the through hole constituting the key groove of the connecting portion, and moving forward while engaging the bolt head with the peripheral edge of the guide groove. Then, the floating body is moved toward and away from the side face of the sheet pile while being restrained by the engaging pin.

  A fixing | fixed part is a member which makes a floating body approach the side surface of a sheet pile, and fixes the position of the said floating body in the state which faced the front edge of the formwork part to the side surface of the sheet pile. For example, when the fixing pin of the cap concrete block is configured with a bolt, the fixing pin is pressed against the side plate by tightening the fixing pin into the nut hole embedded in the side plate through the bolt hole provided in the fixing flange, and the connecting portion is pressed. A fixed flange is restrained with respect to the bottom slab of the shade concrete block, and the floating body is fixed in position via the fixed flange. At this time, if the engagement of the floating body with the bottom plate of the shade concrete block by the connecting portion is such that the upper surface of the floating body is in contact with the lower surface of the bottom plate, the floating body is fixed by fixing the position of the floating body by the fixing portion. Can be brought into close contact with the bottom surface of the bottom plate of the cap concrete block.

  As a concrete bottom mold frame, a foamed polystyrene block having a front edge that closely contacts the side face of the sheet pile, a mold frame portion having a front edge closely contacting the side face of the sheet pile, and the front edge of the bottom plate of the cap concrete block The steel plate is larger than the gap between the side face of the sheet pile, and a configuration in which the front edge of the mold frame part is aligned with the front edge of the floating body and the mold frame part is fixed to the upper surface of the floating body can be exemplified. The foamed polystyrene block serving as the floating body and the steel plate serving as the mold part may be integrated so as not to be connected or separated, or may be freely connected and separated. If the front edge of the formwork part is in close contact with the side surface of the sheet pile, the front edge of the floating body and the front edge of the formwork part are matched, and the formwork part is brought into contact with the upper surface of the floating body and fixed. It becomes a composition. However, if the front edge of the formwork part is not in close contact with the side face of the sheet pile (for example, a shape withdrawn from the side face of the sheet pile), it floats from the formwork part so that the front edge of the floating body can be in close contact with the side face of the sheet pile The body is slightly protruded, and the mold part is brought into contact with and fixed to the upper surface of the floating body.

  In addition, as a concrete bottom mold frame, a styrofoam block with a leading edge where the floating body is in close contact with the side surface of the sheet pile, a reinforcing frame assembled with steel is integrated, and the connecting part approaches the side surface of the sheet pile A configuration in which a key groove is provided in the portion of the reinforcing frame extending in the direction of separating and the fixing portion protrudes from the portion of the reinforcing frame protruding from the back surface of the side plate of the cap concrete block can be exemplified. . The foamed polystyrene block and the reinforcing frame that are the floating body may be integrated so as not to be connected or separated, or may be connected and separated. The reinforcing frame is a reinforcing member that provides sufficient rigidity to a floating body made of a foamed polystyrene block that cannot stand alone against the placed concrete, and provides a foundation for providing a connecting portion and a fixing portion. Further, when the wedge described above is inserted between the bottom surface of the bottom plate and the bottom mold frame, if the rigid reinforcing frame is integrated with the floating body, the wedge is connected to the bottom surface of the bottom plate and the reinforcing frame. Inserting between them, it is easy to lift the front of the bottom formwork and press the upper surface strongly against the front edge of the cap slab.

  The method for constructing a revetment retaining wall according to the present invention uses a bottom formwork having buoyancy to facilitate and reliably attach and collect the bottom formwork. Has the effect of reducing the cost and cost. Usually, the revetment retaining wall is constructed continuously from several tens of meters to several hundreds of meters in the horizontal direction, so the number of bottom molds required for the construction of the revetment retaining wall is very large. The construction method of the revetment retaining wall according to the present invention that brings about the above-described effect greatly improves the conventional construction work. Further, in the construction method, when a wedge is inserted between the bottom surface of the bottom plate of the shaded concrete block and the bottom mold, there is no possibility that the concrete to be placed will leak from the front edge of the bottom plate, and the recovery work is further facilitated. And the effect of ensuring is obtained.

  The shaded concrete block and the bottom mold of the present invention have an effect of realizing the construction method of the revetment retaining wall. In particular, the bottom mold frame that characterizes the method for constructing a revetment retaining wall according to the present invention makes it easy and reliable for a floating body that generates buoyancy, a mold frame part that exhibits a function as a mold frame, and mounting and recovery operations. By adopting a configuration in which the connecting portion and the fixing portion are provided, an effect of realizing a simple and rational configuration as a whole is obtained while optimizing the functions of the floating body, the formwork portion, the connecting portion, and the fixing portion. When a foamed polystyrene block is used for the floating body as a concrete bottom mold, the mold part can be easily made of steel, and the reinforcement frame is integrated with the floating body to improve the rigidity of the floating body. If it is illustrated, the effect that it becomes easy to provide the connection part which consists of a keyway, and the fixed part which consists of a fixed flange further to a floating body will be acquired.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a partial perspective view showing an example of a combination of a cap concrete block 1, a sheet pile 2 and a bottom mold 3 to which the method of constructing a revetment retaining wall of the present invention is applied. FIG. 3 is an enlarged front view showing the bottom mold 3, FIG. 4 is an enlarged plan view showing the bottom mold 3, FIG. 5 is an enlarged side view of the bottom mold 3, and FIG. 6 is another example of the bottom mold 3. FIG. 3 is an enlarged perspective view corresponding to FIG. 2. The construction method of the revetment retaining wall according to the present invention is not limited by the configuration or structure of the cap concrete block 1 or the sheet pile 2, and appropriately determines the configuration or structure of the bottom formwork 3, thereby the cap concrete block 1 and the sheet pile. 2 can be combined. In this example, as shown in FIG. 1, the sheet pile 2 is composed of a round pipe, and the fixing pin 111 and the engaging pin 121 provided on the cap concrete block 1 are respectively bolts and nuts embedded in the side plate 11. The fixing pin 111 is detachably attached to the hole, the fixing flange 333 of the bottom mold 3 is fixed, and the engaging pin 121 is screwed into the nut hole embedded in the bottom plate 12 so as to protrude downward from the bottom plate 12. The key groove 331 of the bottom mold 3 is engaged with the bolt head of the engagement pin 121.

  As shown in FIGS. 2 to 5, the bottom mold frame 3 of this example embeds a reinforcing frame 33 along the upper surface of the foamed polystyrene block 31 to be a floating body, and covers the foamed polystyrene block 31 and the reinforcing frame 33 integrally. Covered with 311 and is configured by fixing a steel plate 32 as a mold part so as to sandwich the cover 311 together with the upper surface of the polystyrene block 31, and provided with a keyway 331 at a portion of the reinforcing frame 33 viewed through the slit of the steel plate 32, A fixed flange 333 is provided on a frame protrusion 332 that protrudes rearward from the reinforcing frame 33. The expanded polystyrene block 31 and the reinforcing frame 33 in this example are integrated so that they cannot be connected and separated and are covered with a cover 311. However, the expanded polystyrene block 31 and the reinforcing frame 33 may be connected and separated. The bottom mold 3 may have a configuration in which one sheet is assigned to each sheet pile 2 (a structure in which left and right protrusions are provided across a semicircular arc-shaped front edge), but in this example, one sheet is disposed between adjacent sheet piles 2. Is assigned. In this case, it is possible to easily determine and maintain the posture of the bottom mold 3 by pressing the front edge of the bottom mold 3 against each side surface of each sheet pile 2 while inserting a protruding portion between adjacent sheet piles 2. There is.

  The foamed polystyrene block 31 as a floating body has a home base shape in a plan view in which a front edge is formed from a symmetrical arc-shaped edge that is in close contact with the side surface of an adjacent sheet pile 2 and a central projecting portion where the arc-shaped edge intersects. is there. The reason why the central protruding portion where the arc-shaped edges intersect is a straight edge is that the connecting portion of the sheet pile 2 is a flat plate. In the range of the steel plate 32, the reinforcing frame 33 is assembled with steel materials symmetrically with respect to the central steel material extending in the front-rear direction, and is embedded so that the upper surface of each steel material follows the upper surface of the expanded polystyrene block 31. As a result, the reinforcing frame 33 can support the steel plate 32 receiving the weight of the cast concrete 5 (see FIG. 11 and subsequent figures) as a whole, and can supplement the rigidity of the steel plate 32. The cover 311 covers and protects the expanded polystyrene block 31, and has a function of concealing the joint portion between the expanded polystyrene block 31 and the reinforcing frame 33 from the outside.

  The reinforcing frame 33 of this example is provided with a key groove 331 that constitutes a connecting portion in a central steel material. The bottom mold 3 is suspended from the bottom plate 12 of the cap concrete block 1 with the key groove 331 engaged with the engagement pin 121. In this example, the reinforcing frame 33 is suspended. Only by hanging from the reinforcing frame 33 and applying buoyancy to the reinforcing frame 33 from below, a load due to the engagement is not applied. Further, the reinforcing frame 33 is provided with a frame protruding portion 332 by causing the central steel material to protrude rearward from the expanded polystyrene block 31. The frame protruding portion 332 provides a gripping portion that is held by the operator's hand during the mounting and collecting operations of the bottom mold 3, and a mounting portion of the fixing flange 333 that constitutes the fixing portion as described above.

  The steel plate 32 has a home base shape in plan view in which a front edge is formed from a symmetrical arc-shaped edge that follows the side surface of the adjacent sheet pile 2 and a central projecting portion where the arc-shaped edge intersects, and the front edge is a polystyrene block. It is slightly smaller than the front edge of 31, and the overall size is shorter in the front-rear direction than the expanded polystyrene block 31. The reason why the front edge is slightly less than the front edge of the expanded polystyrene block 31 is that the front edge of the elastic expanded polystyrene block 31 is placed on the side surface of the sheet pile 2 rather than abutting the front edge of the inelastic steel plate 32 against the side surface of the sheet pile 2. This is due to the fact that the abutted surface is easy to adhere to the side surface of the sheet pile 2. In this case, for example, as shown in FIG. 6, a sponge 35 as a packing material may be attached to the front edge of the expanded polystyrene block 31. Since the sponge 35 does not originally close a gap to be filled with concrete, there is no possibility that a portion where the packing material remains is evaluated as a cross-sectional defect compared to the use of a conventional packing material. Of course, there is no need to use a large shade concrete block that can be used to place sufficient concrete within the range excluding the cross-sectional defect. The reason why the length is shorter in the front-rear direction than the expanded polystyrene block 31 is to reduce the weight of the bottom mold 3 and the material saving, and the steel plate 32 is formed from the front edge of the bottom slab 12 of the cap concrete block 1 and the sheet pile 2. It is preferable to make it slightly larger than the gap with the side surface.

  The steel plate 32 of this example is provided with a slit in the center, and the key groove 331 provided in the reinforcing frame 33 is seen through the slit. The slit is an element that lowers the rigidity of the steel plate 32 of this example. As described above, the slit is sufficiently close to the reinforcing frame 33 so as to support the cast concrete 5 by supporting it uniformly. Secures sufficient rigidity. In other words, it is necessary to attach the steel plate 32 to the upper surface of the expanded polystyrene block 31 so as to be in close contact with the reinforcing frame 33. Therefore, for example, the mounting rod protrudes from the back surface of the steel plate 32, and the mounting rod is screwed to the reinforcing frame 33, or screwed to the reinforcing plate or the like that penetrates the reinforcing frame 33 and is directed to the lower surface of the polystyrene block 31. It is better to improve the integrity of the steel plate 32 and the reinforcing frame 33.

  The keyway 331 of this example extends rearward by the width of the bolt body of the engaging pin 121 from the through hole at the front end into which the bolt head of the engaging pin 121 protruding from the bottom plate 12 of the cap concrete block 1 is inserted. It consists of a guide groove. The fixing flange 333 of this example is formed by bending a plate material having a width equal to that of the steel material constituting the reinforcing frame 33 at a right angle, bolting one plate surface to the frame protruding portion 332, and fixing the other plate surface to the frame protruding portion 332. The bolt hole which consists of a long hole extended in the protrusion direction is provided in the other board surface by the structure made to protrude from. The reason why the bolt hole of the fixing flange 333 is a long hole is to absorb the misalignment between the nut hole of the side plate 11 into which the fixing pin 111 is screwed and the fixing flange, and to form a bottom mold by inserting a wedge 34 described later. This is to cope with a change in posture in the vertical direction 3.

  A procedure for constructing a revetment retaining wall according to the present invention will be described. 7 to 14 are sectional views (FIGS. 7 and 8, FIGS. 11 to 14) and partially enlarged perspective views (FIGS. 9 and 10) showing the procedure for constructing the revetment retaining wall, and FIG. FIG. 8 shows the step of attaching the mold 3 to the bottom plate 12 of the cap concrete block 1, FIG. 8 shows the step of pushing the bottom mold 3 attached to the bottom plate 12 of the cap concrete block 1 toward the sheet pile 2, and FIG. Fig. 10 shows a stage between the bottom mold 3 fixed to the side plate 11 of the cap concrete block 1 and the bottom plate of the cap concrete block 1. FIG. 11 shows the stage where the wedge 34 is driven, and the gap between the front edge of the bottom slab 12 of the cap concrete block 1 and the side surface of the sheet pile 2 is closed by the bottom mold 3 and the side plate 11 of the cap concrete block 1 and the side surface of the sheet pile 2 are The pouring concrete 5 is poured in between. Fig. 12 shows the pouring concrete. FIG. 13 shows the stage in which the bottom mold 3 is left in the free state and away from the sheet pile 2, and FIG. 14 shows the bottom mold 3 Represents the stage of removing the cap from the bottom plate 12 of the cap concrete block 1.

  In order to construct the revetment retaining wall, the sheet pile 2 was driven into the boundary between the land and the sea and fixed to the upper end of the sheet pile 2 as shown in FIG. The cap concrete block 1 is attached to the sea side of the block receiving member 21, and the cap concrete block 4 is attached to the land side of the block receiving member 21. Although the cap concrete block 1 and the cap concrete block 4 are the same type, it is not necessary to attach the fixing pin 111 to the side plate 41 and the engagement pin 121 to the bottom plate 42. The sheet pile 2 is subjected to necessary and sufficient rust prevention treatment up to the height where it is always submerged, but from the viewpoint of cost reduction, the rust prevention treatment is not applied above the range where the sea level height fluctuates due to tides. . For this reason, the range where the said rust prevention process is not performed is covered with the shade concrete block 1, the appearance is prepared, and the rust prevention of the sheet pile 2 is aimed at.

  Here, if the side surface of the sheet pile 2 and the front edge of the bottom slab 12 exactly match, a gap is not generated. However, in reality, a gap is generated, and the bottom mold 3 needs to be attached. Therefore, the cap concrete block 1 of this example is provided with a nut hole in each of the side plate 11 and the bottom plate 12, and a fixing pin 111 (see FIG. 8 described later) as a bolt is later inserted into the nut hole of the side plate 11. The engaging pin 121, which is a bolt, is screwed into the nut hole of the bottom plate 12 in advance and protruded. The cap concrete block 4 places the bottom slab 42 on the excavated ground. The cast concrete 5 is poured between the sheet pile 2 and the shaded concrete block 1 and between the sheet pile 2 and the shaded concrete block 4 (see FIG. 11 and subsequent figures).

  The feature of the present invention is first in the work of attaching the bottom mold 3. Since the bottom mold frame 3 of this example has buoyancy due to the foamed polystyrene block 31, when it is brought down to the bottom slab 12 of the cap concrete block 1, it can be pushed and moved by an underwater worker while floating on the sea surface, for example. Then, when the underwater worker lifts the bottom mold 3 and passes the bolt head of the engagement pin 121 through the through hole provided at the front end of the keyway 331 (see FIG. 2 and others) and advances it slightly, The bolt head of the mating pin 121 is engaged with the guide groove, and the bottom mold 3 is engaged with the bottom slab 12 and is suspended as seen in FIG. At this time, since the bottom mold 3 is suspended only by the engagement pin 121, it can freely rotate in the horizontal direction, and moves forward (towards the sheet pile 2) within a range where the engagement pin 121 does not reach the through hole. (Moving) or retreating (moving away from the sheet pile 2) is free. From this, the bottom mold 3 is moved, for example, by an underwater worker holding the frame protrusion 332 in his / her hand in the horizontal direction or moving forward as seen in FIG.

  The bottom mold 3 suspended from the bottom plate 12 is advanced until the front edge of the expanded polystyrene block 31 is brought into close contact with the side surface of the sheet pile 2, and is fixed to the nut hole of the side plate 11 through the long hole of the fixing flange 333. Is fixed in a state where the bottom mold 3 is in close contact with the bottom plate 12. At this time, if there is a gap between the front edge of the bottom slab 12 of the cap concrete block 1 and the side surface of the sheet pile 2 (see FIG. 9 and subsequent figures), as shown in FIG. The gap is closed by the steel plate 32. At this time, the upper surface of the steel plate 32 is preferably in close contact with the front edge of the bottom plate 12. For this reason, the bottom mold 3 of this example hangs the wedge 34 via a string on the fixing flange 333. After the position of the bottom mold 3 is fixed, the wedge 34 is attached to the bottom plate 12 as shown in FIG. Is inserted between the lower surface of the steel plate and the reinforcing frame 33, and the front of the bottom mold 3 is lifted so that the upper surface of the steel plate 32 is strongly pressed against the front edge of the bottom plate 21 of the cap concrete block 1 (wedge 34). (It is not shown in the figure at the stage where the is not used.) The reason why the wedge 34 is hung from the fixed flange 333 with a string is to prevent the removed wedge 34 from being lost in the recovery operation of the bottom mold 3 described later.

  If the position of the bottom mold 3 is fixed and the gap between the front edge of the bottom slab 12 of the cap concrete block 1 and the side surface of the sheet pile 2 is closed, the sheet pile 2 and the cap concrete block 1 can be seen as shown in FIG. The casting concrete 5 starts to be poured between the sheet pile 2 and the cap concrete block 4. The cast concrete 5 poured between the sheet pile 2 and the cap concrete block 1 is supported by the steel plate 32 of the bottom mold 3. As described above, since the steel plate 32 is supported by the reinforcing frame 33 (see FIG. 2), it can be sufficiently supported even when the cast concrete 5 is increased by pouring. When the cast concrete 5 is poured over the block receiving material 21 in this way, as shown in FIG. 12, the top concrete block 13 which is flush with the buried ground is placed on the land side, and the concrete block 1 Construction of the revetment retaining wall is completed by placing a dam concrete block 14 continuously extending on the side plate 11 on the sea side.

  The feature of the present invention also appears in the recovery work of the bottom mold 3 after the construction of the revetment retaining wall. After the construction of the revetment retaining wall, as shown in FIG. 13, the bottom mold 3 first removes the wedge 34 to loosen the tightness of the bottom mold 3 with respect to the bottom plate 12, and then loosens the fixing pin 111 to fix the fixing flange. In a state where 333 is released, for example, by hitting the frame protrusion 332 with a hammer, the steel plate 32 is peeled off from the cast concrete 5 which is solidified by applying an impact to the reinforcing frame 33. As a result, the bottom mold 3 recovers the free state suspended only by the engaging pins 121, so that the underwater worker now holds the frame protrusion 332 in his hand and moves the bottom mold 3 backward. At this time, since the underwater worker is on the sea surface on the side where the frame protrusion 332 is pulled out and is not directly under the bottom mold 3, even if the bottom mold 3 is unexpectedly released from the engagement pin 121 and dropped, Underwater workers are safe.

  When the bottom mold 3 is sufficiently retracted and the through hole provided at the front end of the keyway 331 (see FIG. 2) reaches the engagement pin 121, the bottom mold 3 can be suspended by the engagement pin 121. As can be seen in FIG. 14, the bottom mold 3 falls toward the sea surface. Here, if it is a conventional bottom mold (see Patent Document 1 and others), it has been submerged as it is, but the bottom mold 3 of the present invention has buoyancy due to the expanded polystyrene block 31, You can float on the sea without being submerged. At this time, the frame protruding portion 332 protrudes, and the underwater worker can easily collect the bottom mold 3 by holding each frame protruding portion 332 of each bottom mold 3 in his / her hand. Further, since the bottom mold 3 is not submerged, after separating all the bottom molds 3 from the bottom plate 12 of the shade concrete block 1 in advance, the bottom mold 3 drifting on the sea surface may be collected, or a large number of bottom molds 3 may be recovered. The mold 3 may be separated from the bottom plate 12 in order and recovered for each separated bottom mold 3.

  Thus, the bottom mold 3 is easily and reliably collected. In this example, the fixing pin 111 and the engaging pin 121 can also be removed from the respective nut holes and recovered. From this, it is preferable that each nut hole remaining in the cap concrete block 1 is subjected to rust prevention treatment, but the fixing pin 111 and the engagement pin 121 do not particularly require rust prevention treatment. However, for example, if the engagement pin 121 is left as it is after the bottom mold 3 is collected, the engagement pin 121 needs to be subjected to a rust prevention treatment. Actually, it is often the case that the fixed pin 111 is submerged due to tides, so that it is preferable that the fixed pin 111 and the engaging pin 121 are all subjected to rust prevention treatment including the nut hole. Similarly, the reinforcing frame 33 and the steel plate 32 of the bottom mold 3 are preferably subjected to rust prevention treatment.

It is a fragmentary perspective view which shows an example of the combination of the cap concrete block which applies the construction method of the revetment retaining wall of this invention, a sheet pile, and a bottom formwork. It is a partial fracture expansion perspective view which shows a bottom mold. It is an enlarged front view which shows a bottom mold. It is an enlarged plan view which shows a bottom mold. It is an enlarged side view of a bottom mold. It is an expansion perspective view equivalent to FIG. 2 which shows the bottom mold frame of another example. It is sectional drawing showing the step which attaches a bottom formwork to the bottom slab of a cap concrete block. It is sectional drawing showing the step which is pushing in toward the sheet pile the bottom form frame attached to the bottom slab of the cap concrete block. It is a partial expansion perspective view showing the step which fixes the bottom formwork pushed in toward the sheet pile to the side plate of a cap concrete block. It is a partial expansion perspective view showing the stage which struck a wedge between the bottom form frame fixed to the side plate of the cap concrete block, and the base plate of the cap concrete block. FIG. 5 is a cross-sectional view showing a stage in which cast concrete is poured between the side plate of the cap concrete block and the side surface of the sheet pile by closing the gap between the front edge of the bottom plate of the cap concrete block and the side surface of the sheet pile with a bottom mold. It is sectional drawing showing the stage which finished casting pouring concrete and has arrange | positioned the top plate concrete block and the dam concrete block. It is sectional drawing showing the step which is making the bottom mold frame into a free state and keeping away from a sheet pile. It is sectional drawing showing the stage which removed the bottom formwork from the bottom plate of the cap concrete block.

Explanation of symbols

1 concrete block
11 side version
111 Fixing pin
12 Bottom plate
121 engagement pin 2 sheet pile 3 bottom mold
31 Styrofoam block
32 Steel plate (formwork part)
33 Reinforcement frame
331 keyway
332 Frame protrusion
333 fixed flange 4 concrete block 5 cast concrete

Claims (6)

When building a revetment retaining wall by covering a sheet pile with a cap concrete block composed of a side plate that is lowered vertically and a bottom plate that protrudes from the lower edge of the side plate, the side plate of the cap concrete block and the sheet pile A bottom mold having buoyancy is used to pour the cast concrete between the sides, and before pouring the cast concrete, the bottom mold is brought into close contact with the bottom surface of the cap concrete block bottom plate, The gap between the front edge of the sheet pile and the side face of the sheet pile is closed from below by the bottom mold, and after pouring concrete is poured, the bottom mold is separated from the bottom surface of the bottom plate of the cap concrete block, and the bottom mold is submerged. How to build a revetment retaining wall that can be recovered without any problems. When the bottom mold is in close contact with the bottom surface of the bottom plate of the concrete block, the bottom mold is in close contact with the bottom surface of the bottom plate by engaging a part of the bottom mold with the bottom plate, and between the bottom mold and the bottom plate. Insert a wedge between the bottom plate bottom surface and the bottom mold frame from the side plate side behind the engagement site, lift the front from the engagement site of the bottom mold frame, and the upper surface to the front edge of the bottom plate of the cap concrete The concrete to be placed by pressing firmly is prevented from leaking, and the area where the concrete to be placed adheres to the bottom mold is limited to the gap between the front edge of the bottom plate of the cap concrete block and the side face of the sheet pile. The construction method of the revetment retaining wall of Claim 1 which makes collection | recovery work of a mold easy. A cap concrete block used in the method for constructing a revetment retaining wall according to claim 1, wherein an engagement pin is provided on the bottom plate and a fixing pin is provided on the side plate, and the engagement pin is a cap concrete block. The bottom pin is protruded from the bottom surface of the bottom plate, and in the state where the key groove of the bottom mold frame is brought into close contact with the bottom plate, the bottom mold frame is restrained to approach and separate from the side surface of the sheet pile, A shaded concrete block that protrudes from the back side of the side plate of the shaded concrete block and in which the bottom mold is in close contact with the bottom surface of the shaded block of the shaded concrete block in a state where the fixing flange of the bottomed mold is connected. It is a bottom formwork used for the construction method of the revetment retaining wall of any one of Claim 1 or 2, Comprising: A floating body is provided with a formwork part, a connection part, and a fixing | fixed part, and a floating body is self and formwork Part, connecting part and fixed part is a structure that generates buoyancy against the combined weight, and the mold part has a front edge that follows the side of the sheet pile, and the front edge of the bottom plate of the cap concrete block As a member having a plane larger than the gap between the sheet pile and the side surface of the sheet pile, and the connecting portion is arranged on the side surface of the sheet pile as a member having a keyway extending in a direction in which the floating body approaches and separates. With the engaging pin provided along the upper surface of the body and protruding from the lower surface of the bottom plate of the cap concrete block engaged with the key groove, the floating body is held close to and away from the side surface of the sheet pile while restraining the floating body. On the back of the side plate of the shade concrete block As a member consisting of one fixed flange, it protrudes from the upper surface of the floating body, and with the fixing pin protruding from the back surface of the side plate of the cap concrete block connected to the fixed flange, the float body is attached to the bottom plate of the cap concrete block. A bottom mold that is in close contact with the bottom surface. The floating body is a styrofoam block having a front edge closely contacting the side face of the sheet pile, and the mold part has a front edge imitating the side face of the sheet pile, and the front edge of the bottom plate of the cap concrete block and the side face of the sheet pile The bottom mold according to claim 4, wherein the bottom mold is a steel plate larger than the gap, and the mold frame is fixed to the upper surface of the float by aligning the front edge of the mold with the front edge of the float. The floating body is a styrofoam block having a leading edge that is in close contact with the side surface of the sheet pile, and is integrally formed with a reinforcing frame assembled with a steel material, and the connecting portion extends in a direction in which the floating body approaches and separates from the side surface of the sheet pile. The bottom mold according to claim 4, wherein a key groove is provided in a portion of the reinforcing frame, and the fixing portion protrudes from the portion of the reinforcing frame protruding from the back surface of the side plate of the cap concrete block.

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