JP6751694B2 - Insertor for forming sheath connection port, molding method of sheath connection port and installation method of concrete segment - Google Patents

Description

The present invention relates to an inserter for forming a sheath connection port, a method for forming a sheath connection port, and a method for installing a concrete segment.

Conventionally, as a precast method, a concrete segment is manufactured in advance at a factory, and the concrete segment is assembled and joined at the site. Especially in the case of a bridge, a PC cable is inserted into a plurality of concrete segments assembled at the site and joined in a stressed state by pulling.

At this time, a sheath for inserting a PC cable is embedded in each concrete segment. Since the PC cable penetrates the concrete segment, the sheath is embedded so that the open end faces the end face of the concrete segment. Then, the pair of concrete segments are arranged so that the sheath opening ends of the respective end faces are continuous with each other, and the PC cable is inserted into the connected sheath to fill the grout and integrate them.

A method for forming a sheath connection port provided on a block girder joint surface when forming a post-tension block girder in a space area on both sides or one side of the partition surface using an end surface of a partition plate or a ready-made block as a partition surface is described. ing.

In the conventional method, a columnar solid rubber member is inserted into the opening end of the sheath connection pipe piped in the block girder molding space area of the conduction hole that opens in the partition surface, and concrete is poured in this state. I have to. Due to the design of block girder molding, it is necessary to install the sheath diagonally, and when the block girder is separated from the partition surface after the concrete is hardened, the weight of each concrete segment is heavy and the concrete segment is separated in the horizontal direction. Then, the solid rubber member that is tilted and fixed to the formwork interferes with the peripheral edge of the conductive hole of concrete that moves horizontally, and an excessive force is applied to the peripheral edge of the conductive hole, causing peeling damage and labor for repair. There is a problem that occurs.

Therefore, for example, as in Patent Document 1, a wide mouth having a diameter larger than the outer diameter of the sheath is provided at the opening end of the sheath connecting pipe to be piped in the block girder forming space area of the conduction hole opened in the partition surface, via the connecting sheath. A connecting pipe having a portion is connected, and an annular crimping member made of an elastic body whose inner peripheral surface is reinforced by a ring is inserted into the wide mouth portion of the connecting pipe to form a guide pipe having a predetermined length at one end. It is inserted into the sheath through the inside of the crimping member, and the other end is inserted and piped so as to protrude to the outside of the conduction hole on the partition surface, and the connecting pipe is moved toward the partition surface to partition the open end of the annular crimping member. A method is known in which concrete is placed in the block girder forming space area on both sides or one side of the partition surface while being crimped and held on the surface. As a result, when the block girder is separated from the partition surface after the concrete is hardened, the partition surface can be smoothly separated from the opening end of the annular crimping member and the ring, and the block girder end surface is subjected to the conventional method of this type. It is possible to form a beautiful sheath connection conduction port without peeling damage of concrete such as.

Japanese Patent No. 3784923

However, in the above-mentioned Patent Document 1, the tubular crimping member is not sufficiently fixed only by being pressed against the partition surface, and is easily displaced when a force is applied such as when placing concrete. In particular, when the guide pipe is not passed through the inside of the sheath, there is a problem that the path of the sheath is interrupted, a part of the sheath is blocked with concrete after the concrete is placed, and the PC steel wire cannot be inserted as it is.

The present invention has been made in view of the above points, and an object of the present invention is to form a sheath connection port that is surely free from peeling and damage of concrete with a simple structure without deviation.

In order to achieve the above object, in the present invention, an insertion tool for forming a sheath connection port is inserted into the end face of the concrete segment so as to be easily disengaged from the opening end of the desired sheath connection pipe.

Specifically, in the first invention, it is inserted inside the open ends of a pair of sheath connecting pipes embedded in opposite positions on the end faces of a pair of concrete segments formed in a state of being butted with each other via a formwork. For inserters for forming sheath connection ports
The inserter for forming the sheath connection port is
A core material having an outer diameter smaller than the inner diameter of the opening end of the pair of sheath connecting pipes and being inserted with an elastic member wound around the opening ends of the pair of sheath connecting pipes.
It is connected to the core material, has an outer diameter larger than the outer diameter of the opening ends of the pair of sheath connecting pipes, and is provided with an enlarged diameter flange that abuts on the mold.

According to the above configuration, the inner diameter of the periphery of the sheath connection port can be expanded, and the inserter for forming the sheath connection port does not get caught in the periphery of the sheath connection port and easily comes off after placing the concrete. It does not come off. Further, by expanding the inner diameter of the periphery of the sheath connection port, it becomes easier to attach the core to connect the sheath connection pipe when the concrete segments are butted. Further, if the enlarged diameter flange is obliquely processed, the sheath connecting pipe side can be configured so as not to be obliquely processed.

In the second invention, at the end face of the concrete segment abutted against the end face of the ready-mixed concrete segment, the open end of the ready-made sheath connecting pipe embedded in the ready-made concrete segment and the sheath connection embedded at a position facing the open end. Targeting an inserter for forming a sheath connection port, which is inserted inside the opening end of the ready-made sheath connecting pipe and the opening end of the sheath connecting pipe so as to straddle the opening end of the pipe.
The inserter for forming the sheath connection port is
A cylindrical core material around which an elastic member is wound, which has an outer diameter smaller than the inner diameter of the open end and is inserted so as to straddle the open end of the ready-made sheath connecting pipe and the open end of the sheath connecting pipe.
An enlarged diameter connected to the core material, having an outer diameter larger than the outer diameter of the open end of the sheath connecting pipe, and abutting on the peripheral edge of the open end of the ready-made sheath connecting pipe on the end face of the ready-made concrete segment. It has a flange.

According to the above configuration, the inner diameter of the periphery of the sheath connection port can be expanded, and the inserter for forming the sheath connection port does not get caught in the periphery of the sheath connection port and easily comes off after placing the concrete. It does not come off. Further, by expanding the inner diameter of the periphery of the sheath connection port, it becomes easier to attach the core to connect the sheath connection pipe when the concrete segments are butted. Further, if the enlarged diameter flange is obliquely processed, the sheath connecting pipe side can be configured so as not to be obliquely processed.

In the third invention, in the end faces of a pair of concrete segments formed in a state of being abutted with each other via a formwork, a sheath connection port inserted inside the opening ends of a pair of sheath connection pipes embedded at opposite positions. For molding inserts, the above sheath connection port molding inserts are
A core material having an outer diameter smaller than the inner diameter of the opening end of the pair of sheath connecting pipes and being inserted with an elastic member wound around the opening ends of the pair of sheath connecting pipes.
It is equipped with a fixing member that fixes the core material to the mold.
Between the core material and the elastic member, a friction reducing means for reducing the frictional resistance between the two is provided.

According to the above configuration, when the concrete segment is removed from the formwork after the concrete is cast, the elastic member is easily removed from the core material, so that the concrete around the sheath connection port is not peeled off. Further, since the insertion tool for forming the sheath connection port is fixed to the mold by the fixing member, it does not shift from the mold.

In the fourth invention, in the third invention,
The core material is a cylindrical member, and a flange portion is formed on the end surface of the cylindrical member.
The flange portion is configured to come into contact with the mold.

According to the above configuration, since the flange portion can be used to fix the concrete to the formwork, the gap between the formwork and the formwork can be closed, and the concrete is less likely to flow into the formwork when the concrete is placed.

In the fifth invention, in the third invention,
The core material is a pair of bottomed cylindrical members.
The pair of bottomed cylindrical members are configured to be able to be fastened to the formwork.

According to the above configuration, the core material can be more firmly fixed to the formwork, so that the concrete is less likely to flow into the sheath connecting pipe when the concrete is placed.

In the sixth invention, at the end face of the concrete segment abutted against the end face of the ready-mixed concrete segment, the open end of the ready-made sheath connecting pipe embedded in the ready-made concrete segment and the sheath connection embedded at a position facing the open end. Targeting an inserter for forming a sheath connection port, which is inserted inside the opening end of the ready-made sheath connecting pipe and the opening end of the sheath connecting pipe so as to straddle the opening end of the pipe.
The inserter for forming the sheath connection port is
A cylindrical core material around which an elastic member is wound, which has an outer diameter smaller than the inner diameter of the open end and is inserted so as to straddle the open end of the ready-made sheath connecting pipe and the open end of the sheath connecting pipe.
It is provided with a flange that comes into contact with the peripheral edge of the open end of the prefabricated sheath connecting pipe on the end face of the prefabricated concrete segment.
Between the core material and the elastic member, a friction reducing means for reducing the frictional resistance between the two is provided.

According to the above configuration, when the concrete segment is removed from the ready-made concrete segment after the concrete is cast, the elastic member is easily removed from the core material, so that the concrete around the sheath connection port is not peeled off. Further, since the core material is inserted in a press-fitted state so as to straddle the open end of the ready-made sheath connecting pipe and the open end of the sheath connecting pipe, the sheath connecting port forming insert does not shift from the mold.

In the seventh invention, the core material inserted with the elastic member wound around and the core material connected to the core material have an outer diameter larger than the outer diameter of the open ends of the pair of sheath connecting pipes, and the formwork The process of preparing an inserter for forming a sheath connection port provided with an enlarged diameter flange that comes into contact with the
The process of piping the sheath at the position corresponding to the sheath connection port,
The step of fixing the insertion tool for forming the sheath connection port at the position corresponding to the sheath connection port of the mold, and
The process of inserting the sheath connection port forming insert into the open ends of the sheath connection tubes on both sides of the mold, and
The process of placing concrete on both sides of the formwork to form a pair of concrete segments,
The process of removing a pair of concrete segments from both sides of the formwork,
The process of removing the sheath connection port forming insert from the concrete segment and
A step of inserting a core into the sheath connection port of the concrete segment on one side obtained by removing the sheath connection port forming insert, and
The configuration includes a step of abutting the pair of concrete segments so that the core is inserted into the sheath connection port of the other concrete segment.

According to the above configuration, the inner diameter of the periphery of the sheath connection port can be expanded, and the inserter for forming the sheath connection port does not get caught in the periphery of the sheath connection port and easily comes off after placing the concrete. It does not come off. Further, by expanding the inner diameter of the periphery of the sheath connection port, it becomes easier to attach the core to connect the sheath connection pipe when the concrete segments are butted. Further, if the enlarged diameter flange is obliquely processed, the sheath connecting pipe side can be configured so as not to be obliquely processed. When the pair of concrete segments are removed from both sides of the formwork, the sheath connection port forming insert may be removed from the concrete segments at the same time.

In the eighth invention, the core material inserted with the elastic member wound around and the core material connected to the core material have an outer diameter larger than the outer diameter of the open end of the sheath connecting pipe, and hit the mold. The process of preparing an inserter for forming a sheath connection port having an enlarged diameter flange in contact with it,
The process of piping the sheath at the position corresponding to the sheath connection port of the ready-made concrete segment,
A step of inserting the ready-made sheath connecting pipe embedded in the ready-made concrete segment and the insertion tool for forming the sheath connecting port so as to straddle the open end of the sheath connecting pipe.
The process of placing concrete in the above formwork and
The process of removing the concrete segment from the formwork above
The process of removing the sheath connection port forming insert from the concrete segment and
The process of inserting the core into the sheath connection port in the concrete segment formed by removing the sheath connection port forming insert, and
The configuration includes a step of abutting the concrete segment against the ready-made concrete segment so that the core is inserted into the sheath connection port of the ready-made concrete segment.

According to the above configuration, if the enlarged diameter flange is obliquely processed, the sheath connecting pipe side does not need to be obliquely processed. Further, the inner diameter of the periphery of the sheath connection port can be expanded, and the elastic member easily comes off from the core material when the concrete segment is removed from the formwork after placing the concrete, so that the concrete around the sheath connection port does not peel off. Further, by expanding the inner diameter of the periphery of the sheath connection port, it becomes easier to attach the core to connect the sheath connection pipe when the concrete segment is abutted against the ready-made concrete segment. When the concrete segment is removed from the ready-made concrete segment, the sheath connection port forming insert may be removed from the concrete segment at the same time.

The ninth invention is premised on a method of forming a sheath connection port for forming a sheath connection port on the concrete segment when forming a concrete segment on both sides of the formwork.

The molding method of the sheath connection port is
The process of preparing an inserter for forming a sheath connection port in which an elastic member is wound around a core material, and
The process of piping the sheath at the position corresponding to the sheath connection port and
The step of fixing the insertion tool for forming the sheath connection port at the position corresponding to the sheath connection port of the mold, and
The process of inserting the sheath connection port forming insert into the open ends of the sheath connection tubes on both sides of the mold, and
The process of placing concrete in the above formwork and
Including the step of removing the concrete segment from the formwork
In the step of removing the concrete segment, the elastic member is configured to be detached from the core material.

According to the above configuration, when the concrete segment is removed from the formwork after the concrete is cast, the elastic member is removed from the core material, so that the concrete around the sheath connection port is not peeled off. Further, since the insertion tool for forming the sheath connection port is fixed to the mold, it does not shift from the mold.

The tenth invention is premised on a method for forming a sheath connection port for forming a sheath connection port on the concrete segment when the concrete segment is formed at a position facing the end face of the ready-made concrete segment.

The molding method of the sheath connection port is
The process of preparing an inserter for forming a sheath connection port in which an elastic member is wound around a core material, and
The process of piping the sheath at the position corresponding to the sheath connection port and
A step of inserting the ready-made sheath connecting pipe embedded in the ready-made concrete segment and the insertion tool for forming the sheath connecting port so as to straddle the open end of the sheath connecting pipe.
The process of placing concrete in the formwork and
Including the step of removing the concrete segment from the formwork
In the step of removing the concrete segment, the elastic member is configured to be detached from the core material.

According to the above configuration, when the concrete segment is removed from the ready-made concrete segment after the concrete is cast, the elastic member is easily removed from the core material, so that the concrete around the sheath connection port is not peeled off. Further, since the core material is inserted in a press-fitted state so as to straddle the open end of the ready-made sheath connecting pipe and the open end of the sheath connecting pipe, the sheath connecting port forming insert does not shift from the mold.

As described above, according to the present invention, the inner diameter of the sheath connection port is expanded by using a diameter-expanding flange having an outer diameter larger than the outer diameter of the open end of the sheath connection pipe. Further, when the concrete segment is removed, the elastic member of the insert for forming the sheath connection port is separated from the core material. According to these inventions, it is possible to surely form a sheath connection port without peeling and damage of concrete with a simple structure.

It is sectional drawing which shows the state which concrete was placed with the insertion tool for forming a sheath connection port which concerns on Embodiment 1 of this invention inserted. It is a perspective view which shows the outline of the state in which the insertion tool for forming a sheath connection port which concerns on Embodiment 1 of this invention is fixed to a mold. It is sectional drawing which shows the state which concrete was placed with the insertion tool for forming a sheath connection port which concerns on the modification of Embodiment 1 of this invention inserted. It is a perspective view which shows the outline of the state which the insertion tool for forming a sheath connection port which concerns on the modification of Embodiment 1 of this invention is fixed to a mold. It is sectional drawing which shows the state which concrete was placed with the insertion tool for forming a sheath connection port which concerns on Embodiment 2 of this invention inserted. It is sectional drawing which shows the state which concrete was placed with the insertion tool for forming a sheath connection port which concerns on Embodiment 3 of this invention inserted. It is a perspective view which shows the outline of the state in which the insertion tool for forming a sheath connection port which concerns on Embodiment 3 of this invention is fixed to a mold. It is sectional drawing which shows the state which concrete was placed with the insertion tool for forming a sheath connection port which concerns on Embodiment 4 of this invention inserted. It is sectional drawing which shows the state which concrete was placed with the insertion tool for forming a sheath connection port which concerns on Embodiment 5 of this invention inserted. It is sectional drawing which shows the state which a core is inserted into one sheath connection port, and is attracted to the other concrete segment. It is sectional drawing which shows the state which a pair of concrete segments are butted with the core inserted in the sheath connection port. It is sectional drawing which shows the state which concrete was placed with the insertion tool for forming a sheath connection port which concerns on the modification of Embodiment 5 of this invention inserted.

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

(Embodiment 1)
-Structure of inserter for forming sheath connection port-
FIG. 1A shows a state in which concrete is cast with the insertion tool 10 for forming a sheath connection port according to the first embodiment of the present invention inserted. The sheath connecting pipe 3 is embedded so that the open end 3a faces the end surface 2a of the concrete segment 2. That is, in the end faces 2a of the pair of concrete segments 2 formed in a state of being butted with each other via the formwork 1, the pair of sheath connecting pipes 3 are embedded in the formwork 1 at positions facing each other with the for example circular opening 1a interposed therebetween. Is done. On the side opposite to the end surface 2a of the sheath connecting pipe 3, a spiral portion 3b having a spiral unevenness for inserting a long connected sheath (not shown) similarly embedded in the concrete segment 2 is formed. It is formed. The sheath connecting pipe 3 is made of, for example, a resin molded product such as polyvinyl chloride, but may be a metal molded product or the like. As shown in FIG. 1A, in the sheath connecting pipe 3 before concrete placement, a long connected sheath is fixed to the reinforcing bar frame with a gradient as needed, so that the sheath connecting pipe 3 is perpendicular to the end surface 2a of the concrete segment 2. It is often embedded at an angle.

Then, before placing concrete, the sheath connection port forming insert 10 is provided inside the opening end 3a of the pair of sheath connection pipes 3.

As also shown in FIG. 1B, the sheath connection port forming insert 10 includes a core material 11 having an outer diameter smaller than the inner diameter of the opening end 3a of the pair of sheath connection pipes 3. The core material 11 is made of a cylindrical member, for example, a metal pipe having a thin plate thickness. A flange portion 11a is formed at the open end of the end surface of the cylindrical member. The flange portion 11a has, for example, a rectangular plate-like outer shape, and is fixed to the end face of the core material 11 by welding. Then, the flange portion 11a is fixed by the wood screw 12 as a fixing member in a state of being in contact with the formwork 1. In the present embodiment, the fixing member is composed of wood screws 12, but may be nails, bolts, adhesives, or the like, and the shape of the flange portion 11a may be ring-shaped.

The sheath connection port forming insert 10 is inserted in a state where a rubber sheet 13 as an elastic member is wound around an opening end 3a of a pair of sheath connection tubes 3. The rubber sheet 13 is made of, for example, a rubber member having a width and thickness that is easy to wind, and reduces the frictional resistance between the core material 11 and the rubber sheet 13 to reduce friction between detergent, oil, grease, and the like. It is desirable that a lubricant is applied as a means. As a friction reducing means, a device other than the lubricant may be added to make the rubber sheet 13 easily come off from the core material 11. For example, the diameter of the rubber sheet 13 may be set larger than the diameter of the core material 11 in order to reduce the contact area. Further, the rubber sheet 13 or the core material 11 having a low coefficient of friction may be used, or the rubber sheet 13 or the core material 11 may be surface-modified such as a coating for reducing friction. If the outer diameter of the sheath connection port forming insert 10 with the rubber sheet 13 wound is slightly smaller than the inner diameter of the sheath connection tube 3, it is easy to insert the sheath connection tube 3.

-How to mold the sheath connection port-
Next, a method of forming the sheath connection port 20 in which the sheath connection port 20 is formed in the concrete segment 2 when the concrete segment 2 is formed on both sides of the formwork 1 will be described.

First, in the preparatory step, an inserter 10 for forming a sheath connection port in which the rubber sheet 13 is wound around the core material 11 is prepared. When winding the rubber sheet 13 around the core material 11, it is desirable to wind the rubber sheet 13 so that there is no gap between it and the flange portion 11a. Before winding the rubber sheet 13 around the core material 11, a lubricant for reducing the frictional resistance between the core material 11 and the rubber sheet 13 is applied between the core material 11 and the rubber sheet 13.

Next, although not shown in detail, the formwork 1 in which the reinforcing bars are arranged at predetermined intervals is installed. At this time, the sheath connection port forming inserts 10 are fixed to both sides of the opening 1a of the mold 1. For example, the sheath connection port forming insert 10 is fixed to the peripheral edge of the opening 1a with a fixing member such as a wood screw 12 or a nail.

Next, the sheath is piped at a position corresponding to the sheath connection port 20.

Next, the sheath connecting pipe 3 is connected to the end of the sheath. Alternatively, the sheath connecting pipe 3 is connected to the end of the sheath before piping.

Next, the open end 3a of the sheath connection tube 3 is connected to the corresponding sheath connection port forming insert 10. Since the rubber sheet 13 has appropriate elasticity, it is easy to press-fit the sheath connection port forming insert 10 into the opening end 3a.

Next, a guide pipe 4 for securing a space for the PC steel wire is inserted inside the sheath. The guide pipe 4 is made of, for example, a cross-linked polyethylene pipe, and when the outer diameter thereof is close to the inner diameter of the sheath connecting pipe 3, the thickness of the rubber sheet 13 may be made as thin as possible to facilitate the passage of the guide pipe 4. ..

Next, concrete is placed in the formwork 1.

Then, after the concrete has hardened, the concrete segment 2 is removed from the formwork 1. In the step of removing the concrete segment 2, the rubber sheet 13 comes off from the core material 11.

As described above, in the present embodiment, when the concrete segment 2 is removed from the formwork 1 after the concrete is cast, the rubber sheet 13 is easily removed from the core material 11 due to the action of the lubricant, so that the concrete around the sheath connection port 20 is formed. It does not come off.

Further, in the present embodiment, since the flange portion 11a can be used to fix the mold to the mold 1, the space between the flange portion 11a and the mold 1 can be closed, and the sheath connection port forming insert 10 can be attached to the mold 1. The sheath connection pipe 3 makes it difficult for the concrete to flow in when the concrete is placed.

As described above, according to the present embodiment, in the step of removing the concrete segment 2, the rubber sheet 13 of the sheath connection port forming insert 10 is detached from the core material 11, so that the concrete segment 2 is displaced by a simple configuration. It is possible to reliably form the sheath connection port 20 without peeling and damaging the concrete.

-Modification example-
2A and 2B show an inserter 10'for forming a sheath connection port according to a modified example of the embodiment of the present invention, and are different from the above embodiment in that the shape of the core material 11'and the method of fixing to the mold 1 are different. different. In the following modifications and embodiments, the same parts as those in FIGS. 1A and 1B are designated by the same reference numerals, and detailed description thereof will be omitted.

In this modification, as shown in FIG. 2A, the mold 1 is not provided with an opening 1a having the same size as the inner diameter of the sheath connecting pipe 3, but is provided with only a small first bolt insertion hole 1a'. ..

The sheath connection port forming insert 10'of this modified example has a plate shape in which the flange portion 11a'is opened only by the second bolt insertion hole 11b', which is similar to the first bolt insertion hole 1a'. There is. That is, in the present embodiment, the flange portion 11a'is composed of a rectangular plate rather than a flange, and is used when concrete is cast without passing the guide pipe 4 inside. Also in this modified example, a lubricant for reducing the frictional resistance between the core material 11'and the rubber sheet 13 is applied.

By inserting the fixing bolts 12'into the first and second bolt insertion holes 1a'and 11b' and tightening them with nuts, the pair of core members 11'are firmly fixed to the mold 1.

In the present embodiment, since the fixing bolt 12'is firmly fixed at the center, it is not necessary to fix the wood screw 12.

At the time of die-cutting after placing concrete, the inserter 10'for forming the sheath connection port remains in the formwork 1 and the rubber sheet 13 falls off, so that the concrete segment 2 is not damaged.

As described above, even in this modification, the rubber sheet 13 can be more easily detached from the core material 11, so that the rubber sheet 13 is surely detached from the core material 11 at the time of die cutting after concrete placement, and the sheath connection port is formed. Insertion tool 10'can be easily removed.

(Embodiment 2)
FIG. 3 shows an insertion tool 110 for forming a sheath connection port according to a second embodiment of the present invention, which is different from the first embodiment in that the shape of the core material 111 is different.

That is, in the present embodiment, the core material 111 is a cylindrical shape having a length longer than that of the first embodiment and a length straddling the opening 1a, and one flange portion 111a is provided on the outer periphery thereof. The core material 111 does not have the formwork 1 sandwiched between the two flange portions 111a as in the first embodiment. The flange portion 111a is fixed to the peripheral edge of the opening 1a by a wood screw 12 or the like. Also in this embodiment, a lubricant for reducing the frictional resistance between the core material 111 and the rubber sheet 13 is applied between the core material 111 and the rubber sheet 13.

Since only one flange portion 111a is provided in the sheath connection port forming insert 110 according to the present embodiment, it is easy to attach the sheath connection port forming insert 110 to the opening 1a.

Therefore, also in the present embodiment, in the step of removing the concrete segment 2, the rubber sheet 13 of the sheath connection port forming insert 110 can be easily removed from the core material 111, so that the rubber sheet 13 can be easily removed from the core material 111, so that the concrete segment 2 can be reliably configured without deviation. It is possible to form a sheath connection port 20 in which the concrete is not peeled off and damaged.

(Embodiment 3)
4A and 4B show the sheath connection port forming insert 210 according to the third embodiment of the present invention, and are different in that concrete is placed using the end face 2a'of the ready-mixed concrete segment 2'instead of the formwork. Is different from the first embodiment.

Although not shown in detail, the formwork 1 having reinforcing bars arranged on the opposite side of the ready-made concrete segment 2'is installed. In the present embodiment, the formwork 1 is partitioned from the ready-made concrete segment 2'. It does not have a board. A release agent is applied to the end face 2a'of the ready-made concrete segment 2'so that it can be easily peeled off. In the present embodiment, the sheath connection port forming insert 210 is press-fitted into the opening end 3a'of the ready-made sheath connecting pipe 3'instead of the opening 1a of the partition plate. In the present embodiment, the concrete segment 2 is formed so as to abut against the end face 2a'of the ready-made concrete segment 2'.

In the space serving as the end surface 2a of the concrete segment 2, the sheath connection port forming insert 210 is embedded at a position facing the opening end 3a'of the ready-made sheath connection pipe 3'embedded in the ready-made concrete segment 2'. That is, the insertion tool 210 for forming the sheath connection port straddles the end face 2a'inside the opening end 3a'of the ready-made sheath connection pipe 3'and the opening end 3a of the sheath connection pipe 3 embedded in the concrete segment 2 to be created. Will be inserted.

The sheath connection port forming insert 210 has a cylindrical core material 211 around which a rubber sheet 13 is wound, which has an outer diameter smaller than the inner diameter of the opening end 3a. The core material 211 is provided with a flange portion 211a that comes into contact with the peripheral edge of the open end 3a of the ready-made sheath connecting pipe 3'on the end surface 2a'of the ready-made concrete segment 2'. Also in this embodiment, a lubricant for reducing the frictional resistance between the core material 211 and the rubber sheet 13 is applied.

The rubber sheet 13'embedded on the opening end 3a' side of the ready-made sheath connecting pipe 3'does not need to oppose the placing pressure in order to make it easy to come off at the time of pulling, so it has high elasticity and is soft. It is desirable to use the rubber sheet 13'of. At this time, it is desirable that the outer diameter of the portion around which the rubber sheet 13'is wound is slightly larger than the outer diameter of the connecting pipe 3 in order to prevent the rubber sheet 13'from falling off and concrete inflow.

The other rubber sheet 13 is the same as in each of the above embodiments, and it is desirable that the rubber sheet 13 has a certain degree of hardness in order to withstand the driving pressure. In the case of this rigid rubber sheet 13, the outer diameter of the portion around which the rubber sheet 13 of the sheath connection port forming insert 210 including the rubber sheet 13 is wound is larger than the inner diameter of the sheath connection tube 3 so that the rubber sheet 13 can be easily inserted. It is desirable that it is slightly smaller.

Next, a method of forming the sheath connection port 20 for forming the sheath connection port 20 in the concrete segment 2 when the concrete segment 2 is formed at a position facing the end face of the ready-made concrete segment 2'will be described.

First, in the preparatory step, the sheath connection port forming insert 210 in which the rubber sheet 13 is wound around the core material 211 is prepared for the required portion or more of the mold 1. When winding the rubber sheet 13 around the core material 211, it is desirable to wind it so that there is no gap between it and the flange portion 211a. Also in this embodiment, before winding the rubber sheet 13 around the core material 211, a lubricant for reducing the frictional resistance between the core material 211 and the rubber sheet 13 is applied between the core material 211 and the rubber sheet 13.

Next, the sheath connection port forming insert 210 is inserted into the opening end 3a'of the ready-made sheath connection pipe 3'on the ready-made concrete segment 2'side. At this time, it is desirable to press-fit the flange portion 211a until it comes into contact with the end surface 2a'.

Next, the sheath is piped at a position corresponding to the sheath connection port 20 of the mold 1.

Next, the spiral portion 3b of the sheath connecting pipe 3 is connected to the end portion of the sheath. Alternatively, the sheath connecting pipe 3 is connected to the end of the sheath before piping.

Then, the open end 3a of the sheath connection tube 3 is connected to the sheath connection port forming insert 210. Since the rubber sheet 13 has appropriate elasticity, the opening end 3a is press-fitted into the sheath connection port forming insert 210.

Next, concrete is placed in the formwork 1.

Then, after the concrete has hardened, the concrete segment 2 is removed from the ready-made concrete segment 2'. In the step of removing the concrete segment 2, the rubber sheet 13 comes off from the core material 211.

As described above, in the present embodiment, when the concrete segment 2 is removed from the ready-made concrete segment 2'after the concrete is cast, the rubber sheet 13 is easily removed from the core material 211, so that the concrete around the sheath connection port 20 is not peeled off.

Further, in the present embodiment, the gap between the flange portion 211a and the end face 2a'can be closed, and the concrete is less likely to flow from the sheath connecting pipe 3 or the ready-made sheath connecting pipe 3'when the concrete is placed.

Therefore, also in the present embodiment, in the step of removing the concrete segment 2 from the ready-made concrete segment 2', the rubber sheet 13 of the insertion tool 210 for forming the sheath connection port is easily removed from the core material 211, which is simple. It is possible to surely form the sheath connection port 20 without peeling damage of concrete without shifting in the configuration.

(Embodiment 4)
FIG. 5 shows the sheath connection port forming insert 310 according to the fourth embodiment of the present invention, which is different from the modified example of the first embodiment in that the shape and the like of the core material 311 are different.

In the present embodiment, the partition plate of the mold 1 is formed through the first bolt insertion hole 1a'as in the modified example of the first embodiment. The core material 311 is a pair of bottomed cylindrical members, and the pair of bottomed cylindrical members can be fastened to the formwork 1. Specifically, a second bolt insertion hole 311a is opened in the center of the bottom surface of the cup-shaped core material 311. Also in this embodiment, a lubricant for reducing the frictional resistance between the core material 311 and the rubber sheet 13 is applied between the core material 311 and the rubber sheet 13.

In the present embodiment, the fixing bolt 312a of the fixing member 312 is inserted into the first bolt insertion hole 1a'and the second bolt insertion hole 311a, and the tightening nuts 312b and 312c are brought into contact with the taper washer 312d to the partition plate. Fasten in the state. As a result, the core material 311 can be more firmly fixed to the mold 1. Therefore, the core material 311 does not shift with respect to the formwork 1 when the concrete is placed, and the concrete is more difficult to flow into the sheath connecting pipe 3.

Therefore, also in the present embodiment, in the step of removing the concrete segment 2, the rubber sheet 13 of the sheath connection port forming insert 310 is easily removed from the core material 311. Therefore, the concrete can be reliably peeled off without being displaced by a simple configuration. An undamaged sheath connection port 20 can be formed.

(Embodiment 5)
FIG. 6A shows the insertion tool 410 for forming the sheath connection port of the fifth embodiment of the present invention, which is different from the first to fourth embodiments mainly in that the shape around the flange portion is different.

That is, the insertion tool 410 for forming the sheath connection port of the present embodiment has an outer diameter smaller than the inner diameter of the opening end 3a of the pair of sheath connection tubes 3 made of polyvinyl chloride or the like, and these pair of sheath connection tubes 3 It has a core material 411 inserted in a state where an elastic member is wound around the opening end 3a of the above. The core material 411 may be a resin molded product or a metal product.

The core material 411 has a second bolt insertion hole 411b as in the fourth embodiment, and is fixed by inserting the fixing bolt 312a of the fixing member 312 into the first bolt insertion hole 1a'of the formwork 1. , Can be fixed to the mold 1.

Further, the sheath connection port forming insert 410 is connected to the core material 411, has an outer diameter larger than the outer diameter of the opening end 3a of the pair of sheath connection pipes 3, and has an enlarged diameter flange that abuts on the mold 1. It is equipped with 411a. As shown in FIG. 6A, if the diameter-expanding flange 411a is diagonally machined at a preset angle, the sheath connecting pipe 3 side can be configured so as not to be diagonally machined.

Next, a method of molding the concrete segment 2 using the sheath connection port forming insert 410 and then installing the concrete segment 2 at the installation location will be described.

First, the above-mentioned insertion tool 410 for forming the sheath connection port is prepared.

Next, after the formwork 1 is installed and the reinforcement is arranged, the sheath is piped at a position corresponding to the sheath connection port.

Next, the insertion tool 410 for forming the sheath connection port is fixed at a position corresponding to the sheath connection port of the mold 1. Specifically, the core material 411 is fixed to the first bolt insertion hole 1a'using the fixing member 312 as in the fourth embodiment.

Next, the sheath connection port forming insert 410 is inserted into the opening ends 3a of the sheath connection pipes 3 on both sides of the mold 1.

Next, as shown in FIG. 6A, concrete is cast on both sides of the formwork 1 to form a pair of concrete segments 2.

Next, the pair of concrete segments 2 are removed from both sides of the formwork 1. In the present embodiment, since the core material 411 is fixed to the mold 1, at that time, the inserter 410 for forming the sheath connection port is detached from the constant segment 2. Since the inner diameter of the sheath connection port peripheral edge is expanded in a trumpet shape by the action of the diameter-expanding flange 411a, the sheath connection port forming insert 410 is easily removed without being caught on the sheath connection port peripheral edge. Moreover, since the rubber sheet 13 is easily removed, the concrete around the sheath connection port is not peeled off.

Next, the core 414 is inserted into the sheath connection port of the one concrete segment 2 formed by removing the sheath connection port forming insert 410. At this time, since the inner diameter of the periphery of the sheath connection port is widened, it is easy to insert the core 414.

Next, as shown in FIG. 6B, the adhesive 415 is applied to the end faces 2a of the pair of concrete segments 2. The type of the adhesive 415 is not particularly limited, and examples thereof include epoxy resin-based adhesives and mortars.

Then, as shown in FIG. 6C, the pair of concrete segments 2 are butted so as to insert the core 414 into the sheath connection port of the other concrete segment 2. At this time, since the outer diameter of the sheath connection port is expanded by the enlarged diameter flange 411a', the core 414 is not caught and the concrete is not damaged. The gaps such as the periphery of the sheath connection port when the pair of concrete segments 2 are abutted are filled with the adhesive 415.

-Modification example 1-
FIG. 6D shows an insertion tool 410'for forming a sheath connection port according to a modification 1 of the present embodiment, and the above embodiment is described only in that a pair of sheath connection pipes 3 embedded in the concrete segment 2 extend linearly. Different from form 5.

That is, in this modification, it is not necessary to incline the enlarged diameter flange 411a'. Even in this case, the increased diameter of the sheath connection port facilitates the removal of the sheath connection port forming insert 410'and the butting of the concrete segment 2 in which the core 414 is fitted.

-Modification example 2-
Although not shown, in the present modification, as in the third embodiment, the prefabricated sheath connection embedded in the prefabricated concrete segment 2'at the end face 2a of the concrete segment 2 abutting against the end face 2a'of the prefabricated concrete segment 2'. The opening end 3a'of the ready-made sheath connecting pipe 3'and the sheath connecting pipe so as to straddle the opening end 3a'of the pipe 3'and the opening end 3a of the sheath connecting pipe 3 embedded at a position facing the opening end 3a'. It may be an insertion tool for forming a sheath connection port that is inserted inside the opening end 3a of 3.

Although not specifically shown, the cylindrical core material 411 around which the rubber sheets 13 and 13'are wound and the enlarged diameter flange 411a are provided as in the fifth embodiment, but the fixing member 312 is not provided. , The ready-made concrete segment 2'may be fixed with a nail or the like using an enlarged diameter flange 411a.

Specifically, first, the sheath is piped at a position corresponding to the sheath connection port of the ready-made concrete segment 2'.

Next, the sheath connection port forming insert 410 is inserted so as to straddle the ready-made sheath connecting pipe 3'embedded in the ready-made concrete segment 2'and the opening ends 3a, 3a'of the sheath connecting pipe 3.

Next, concrete is placed in the formwork 1.

Next, the concrete segment 2 is removed from the formwork 1.

Then, or when the concrete segment 2 is removed, the sheath connection port forming insert 410 is removed from the concrete segment 2.

Next, the core 414 is inserted into the sheath connection port in the concrete segment 2 formed by removing the sheath connection port forming insert 410.

Next, the adhesive 415 is applied to the end faces 2a, 2a'of the pair of concrete segments 2, 2'.

Next, the concrete segment 2 is abutted against the ready-mixed concrete segment 2'so that the core 414 is inserted into the sheath connection port of the ready-mixed concrete segment 2'.

In this way, also in this modification, the diameter of the sheath connection port is increased, so that the insertion tool 410 for forming the sheath connection port can be easily removed, and the concrete segment 2 in which the core 414 is fitted can be easily butted.

(Other embodiments)
The present invention may have the following configuration with respect to the above embodiment.

That is, in the above embodiment, the inner diameter of the opening end 3a of the sheath connecting pipes 3 and 3'is not increased with respect to other portions, but for example, the outer diameter may be gradually increased in a trumpet shape. .. Then, when the concrete segment 2 is pulled apart, the insertion tool for forming the sheath connection port can be easily pulled out. Further, even when the concrete segment 2 is installed at the construction site, the fitting to be inserted into the sheath connecting pipe is easily fitted and the construction is facilitated.

In the fifth embodiment, the core material 411 is fixed to the mold 1 by using the fixing member 312, but it can also be applied to the embodiment in which the guide pipe 4 is inserted as in the first embodiment. In that case, the enlarged diameter flange 411a'may be fixed to the mold 1 by another method different from the fixing member 312, for example, a screw, a nail, or the like.

Further, although details are not shown, in all embodiments, by sandwiching a sheet made of an elastic member such as rubber between the formwork and the flange portion or the enlarged diameter flange, it becomes a cushion when the concrete segment is pulled apart and is damaged by peeling. Is less likely to occur.

It should be noted that the above embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its applications and applications.

1 formwork
1a opening
1a'First bolt insertion hole
2 concrete segment
2'ready-made concrete segment
2a, 2a'end face
2b recess 3 sheath connection pipe
3'ready-made sheath connection tube
3a, 3a'open end
3b spiral part
4 Guide pipe 10, 10', 110, 210, 310, 410, 410' Insertor for forming sheath connection port
11,11', 111,211,311,411 Core material 11a, 11a', 111a, 211a, 311a Flange portion
11b'2nd bolt insertion hole
12 Wood screw (fixing member)
12'Fixing bolt (fixing member)
13, 13'Rubber sheet (elastic member)
20 sheath connection port
312 Fixing member
312a Fixing bolt
312b, 312c tightening nuts
312d taper washer
411a, 411a'Expanded flange
414 core
415 adhesive

Claims (10)

An inserter for forming a sheath connection port that is inserted inside the opening ends of a pair of sheath connection pipes embedded in opposite positions on the end faces of a pair of concrete segments that are formed in a state of being butted through a formwork. hand,
A core material having an outer diameter smaller than the inner diameter of the opening end of the pair of sheath connecting pipes and being inserted with an elastic member wound around the opening ends of the pair of sheath connecting pipes.
A sheath connection port which is connected to the core material, has an outer diameter larger than the outer diameter of the opening ends of the pair of sheath connection pipes, and is provided with an enlarged diameter flange that abuts on the mold. Molding insert. At the end face of the concrete segment abutted against the end face of the ready-mixed concrete segment, the open end of the ready-made sheath connecting pipe embedded in the ready-made concrete segment and the open end of the sheath connecting pipe embedded at a position facing the open end. An inserter for forming a sheath connection port, which is inserted into the open end of the ready-made sheath connection pipe and the open end of the sheath connection pipe so as to straddle the sheath connection pipe.
A cylindrical core material around which an elastic member is wound, which has an outer diameter smaller than the inner diameter of the open end and is inserted so as to straddle the open end of the ready-made sheath connecting pipe and the open end of the sheath connecting pipe.
An enlarged diameter connected to the core material, having an outer diameter larger than the outer diameter of the open end of the sheath connecting pipe, and abutting on the peripheral edge of the open end of the ready-made sheath connecting pipe on the end face of the ready-made concrete segment. An inserter for forming a sheath connection port, which is characterized by having a flange. An inserter for forming a sheath connection port that is inserted inside the opening ends of a pair of sheath connection pipes embedded in opposite positions on the end faces of a pair of concrete segments that are formed in a state of being butted through a formwork. hand,
A core material having an outer diameter smaller than the inner diameter of the opening end of the pair of sheath connecting pipes and being inserted with an elastic member wound around the opening ends of the pair of sheath connecting pipes.
It is equipped with a fixing member that fixes the core material to the mold.
An inserter for forming a sheath connection port, characterized in that a friction reducing means for reducing the frictional resistance between the core material and the elastic member is provided. In the insertion tool for forming a sheath connection port according to claim 3,
The core material is a cylindrical member, and a flange portion is formed on the end surface of the cylindrical member.
An inserter for forming a sheath connection port, characterized in that the flange portion is configured to be in contact with the mold. In the insertion tool for forming a sheath connection port according to claim 3,
The core material is a pair of bottomed cylindrical members.
An inserter for forming a sheath connection port, characterized in that the pair of bottomed cylindrical members can be tightened to the mold. At the end face of the concrete segment abutted against the end face of the ready-mixed concrete segment, the open end of the ready-made sheath connecting pipe embedded in the ready-made concrete segment and the open end of the sheath connecting pipe embedded at a position facing the open end. An inserter for forming a sheath connection port, which is inserted into the open end of the ready-made sheath connection pipe and the open end of the sheath connection pipe so as to straddle the sheath connection pipe.
A cylindrical core material around which an elastic member is wound, which has an outer diameter smaller than the inner diameter of the open end and is inserted so as to straddle the open end of the ready-made sheath connecting pipe and the open end of the sheath connecting pipe.
It is provided with a flange that comes into contact with the peripheral edge of the open end of the prefabricated sheath connecting pipe on the end face of the prefabricated concrete segment.
An inserter for forming a sheath connection port, characterized in that a friction reducing means for reducing the frictional resistance between the core material and the elastic member is provided. A core material that is inserted with an elastic member wound around it, and a diameter-expanded flange that is connected to the core material and has an outer diameter larger than the outer diameter of the open ends of the pair of sheath connecting pipes and abuts on the mold. The process of preparing an inserter for forming a sheath connection port equipped with
The process of piping the sheath at the position corresponding to the sheath connection port,
The step of fixing the insertion tool for forming the sheath connection port at the position corresponding to the sheath connection port of the mold, and
The process of inserting the sheath connection port forming insert into the open ends of the sheath connection tubes on both sides of the mold, and
The process of placing concrete on both sides of the formwork to form a pair of concrete segments,
The process of removing a pair of concrete segments from both sides of the formwork,
The process of removing the sheath connection port forming insert from the concrete segment and
A step of inserting a core into the sheath connection port of the concrete segment on one side obtained by removing the sheath connection port forming insert, and
A method for installing a concrete segment, which comprises a step of abutting the pair of concrete segments so as to insert the core into the sheath connection port of the other concrete segment. A core material that is inserted with an elastic member wound around it, and an enlarged flange that is connected to the core material and has an outer diameter larger than the outer diameter of the open end of the sheath connecting pipe and abuts on the mold. The process of preparing the insert for forming the sheath connection port and
The process of piping the sheath at the position corresponding to the sheath connection port of the ready-made concrete segment,
A step of inserting the ready-made sheath connecting pipe embedded in the ready-made concrete segment and the insertion tool for forming the sheath connecting port so as to straddle the open end of the sheath connecting pipe.
The process of placing concrete in the above formwork and
The process of removing the concrete segment from the formwork above
The process of removing the sheath connection port forming insert from the concrete segment and
The process of inserting the core into the sheath connection port in the concrete segment formed by removing the sheath connection port forming insert, and
A method for installing a concrete segment, which comprises a step of abutting the concrete segment against the ready-made concrete segment so that the core is inserted into the sheath connection port of the ready-made concrete segment. A method of forming a sheath connection port in which a sheath connection port is formed in the concrete segment when forming a concrete segment on both sides of the formwork.
The process of preparing an inserter for forming a sheath connection port in which an elastic member is wound around a core material, and
The process of piping the sheath at the position corresponding to the sheath connection port and
The step of fixing the insertion tool for forming the sheath connection port at the position corresponding to the sheath connection port of the mold, and
The process of inserting the sheath connection port forming insert into the open ends of the sheath connection tubes on both sides of the mold, and
The process of placing concrete in the above formwork and
Including the step of removing the concrete segment from the formwork
A method for forming a sheath connection port, characterized in that, in a step of removing the concrete segment, a core material fixed to the formwork remains together with the formwork, and the elastic member is detached from the core material. A method for forming a sheath connection port in which a sheath connection port is formed in the concrete segment when the concrete segment is formed at a position facing the end face of the ready-made concrete segment.
The process of preparing an inserter for forming a sheath connection port in which an elastic member is wound around a core material, and
The process of piping the sheath at the position corresponding to the sheath connection port and
The step of inserting the sheath connection port forming insert so as to straddle the ready-made sheath connection pipe embedded in the ready-made concrete segment and the open end of the sheath connection pipe, and
The process of placing concrete in the formwork and
Including the step of removing the concrete segment from the formwork
A method for forming a sheath connection port, characterized in that the elastic member is detached from the core material in the step of removing the concrete segment.

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