JP7366732B2 - Inspection method, inspection structure forming jig, and inspection structure manufacturing method - Google Patents

Description

The present invention relates to an inspection structure for inspecting a connection state when connecting concrete structures with a joint member, and a jig for forming the inspection structure.

For example, as shown in FIG. 1 of Patent Document 1 below, a concrete structure 500 such as a deck slab of a bridge or an expressway viaduct is connected to a concrete structure 510, 520 in which sheaths 210, 220 are buried using a filling sheath joint. (Joint member) 100 and are integrated by filling a gap 530 between both concrete structures 510 and 520 with filler concrete 531. After this integration, a tension material (PC steel material) 600 is passed through the sheath and tension is applied to the tension material 600, thereby introducing prestress into the concrete structure 500. After the prestress is introduced, the grout 700 is filled inside the sheaths 210 and 220 and the filling sheath joint 100.

At both ends of the filling sheath joint 100, water stop portions 310, 320 are formed with sealing materials 311, 321 wrapped around them. The water stop portions 310 and 320 prevent the filling concrete 531 filled in the gap portion 530 from flowing into the sheaths 210 and 220.

Japanese Patent Application Publication No. 2018-123672

In the water stop parts 310 and 320 according to Patent Document 1, after inserting the filling sheath joint 100 into the sheaths 210 and 220, it is necessary to check the insertion state of the water stop parts 310 and 320 into the sheaths 210 and 220. is difficult. If the water stop parts 310, 320 are not inserted securely into the sheaths 210, 220, the water stop parts 310, 320 may suddenly fall off from the sheaths 210, 220 during work, and the water stop effect will be impaired. There is a possibility that the filling concrete 531 may flow into the sheaths 210 and 220. Although the insertion state of the sealing materials 311 and 321 can be estimated to some extent from the width of the gap portion 530, it is possible to estimate the insertion state of the sealing materials 311 and 321 to some extent from the size of the width of the gap portion 530. It is difficult to easily grasp the inserted state of the sealing materials 311 and 321 because the sealing materials 311 and 321 are biased toward the sheaths 210 and 220.

Therefore, it is an object of the present invention to easily grasp the insertion state of the joint member into the sheath.

In order to solve the above problems, the present invention includes a main body made of hardened concrete, a hollow cylindrical sheath embedded in the main body, the insertion part opening to the outside of the main body, and a hollow cylindrical sheath embedded in the main body. The inspection structure includes an inspection hole for inspecting the presence or absence of a joint member inserted into the insertion portion.

In this manner, by inspecting the presence or absence of the joint member inserted into the sheath (insertion portion) through the inspection hole, it is possible to easily grasp the state of insertion of the joint member into the sheath. If the inserted state is insufficient, appropriate measures such as pushing the joint member deeper can be quickly taken. Thereby, liquid tightness between the sheath and the joint member can be ensured.

In the configuration, at least a portion of the sheath is made of a transparent material that can transmit visible light, the inspection hole penetrates from the outer surface of the main body to the outer surface of the transparent material, and the transparent material It may be configured such that the presence or absence of the joint member is inspected through.

In this way, the state of insertion of the coupling member into the sheath can be directly observed through the inspection hole and the transparent material. Therefore, it is possible to reliably prevent the liquid tightness between the sheath and the joint member from being impaired due to the joint member being insufficiently inserted.

In the configuration including the transparent material, the axial length of the transparent material that is visually recognized through the inspection hole corresponds to the allowable axial insertion depth when the joint member is inserted into the insertion portion. It is possible to adopt a configuration that corresponds to the width of the range.

In this way, it is possible to quickly determine whether the insertion depth of the joint member is within the permissible range, depending on whether the joint member is visible through the transparent material. Based on the above judgment, it is preferable that the axial length of the transparent material that is visible through the inspection hole be the same as the width of the allowable range, but the axial length should be slightly longer than the width of the allowable range. You can also do that. When the length is slightly longer as described above, the above judgment can be made accurately by, for example, attaching a mark indicating the width of the permissible insertion depth range to the transparent material.

In the structure in which the axial length of the transparent material visually recognized through the inspection hole corresponds to the width of the allowable range of the axial insertion depth of the joint member, the axial end of the joint member has a A seal member is provided to ensure liquid tightness between the joint member and the sheath, and the axial position of the seal member can be inspected through the inspection hole.

In this way, the axial position of the sealing member can be directly viewed through the inspection hole and the transparent material, so that liquid tightness between the sheath and the coupling member can be ensured.

Instead of forming at least a portion of the sheath from a transparent material as described above, the inspection hole may be configured to penetrate from the outer surface of the main body to the inside of the sheath.

In this way, the state of insertion of the joint member inserted into the sheath can be directly inspected, so the inspection work can be performed easily and reliably.

In addition, in the present invention, a core forming an inspection hole for inspecting the presence or absence of a joint member inserted into a hollow cylindrical sheath buried in the main body from the outside of the main body made of hardened concrete. and a fixing means for fixing the core at a predetermined position with respect to the sheath.

In this way, since the core is stably fixed by the fixing means, an inspection hole for inspecting the presence or absence of the joint member from the outside of the main body can be formed at a desired position.

In the above configuration, the core includes a cylindrical outer cylinder pushed up from the surface of the sheath, a pressed member provided inside the outer cylinder so as to face the sheath, and the pressed member. a pressing member that presses the sheath toward the sheath, and the fixing means is a binding member that is wound around the entire outer cylinder, the pressed member, and the pressing member through the outer peripheral surface of the sheath. The pressing member may be pushed toward the pressed member by the tightening force of the binding member.

In this way, the pressed member can be reliably pressed toward the sheath by the pressing member, and the pressed member and sheath can be brought into close contact with each other. Therefore, concrete does not leak from the surface of the sheath, and it is possible to form an inspection hole through which the inside of the sheath can be clearly viewed.

In this invention, the inspection structure has a main body made of hardened concrete, an insertion part opening to the outside of the main body, a hollow cylindrical sheath buried in the main body, and a hollow cylindrical sheath inserted into the insertion part. Since the configuration includes an inspection hole for checking the presence or absence of the coupling member, it is possible to easily check the insertion state of the coupling member into the sheath through the inspection hole. Therefore, appropriate measures can be quickly taken in response to the inserted state, and fluid tightness between the sheath and the coupling member can be ensured.

A sectional view showing a first embodiment of an inspection structure according to the present invention Cross-sectional view showing an example of a joint member FIG. 3 is a cross-sectional view showing an example of a jig for forming an inspection structure according to the first embodiment, in which (a) is before the pressed member is pressed against the sheath, and (b) is after the pressed member is pressed against the sheath. FIG. 3 is a cross-sectional view showing an example of the manufacturing process of the inspection structure according to the first embodiment, in which (a) a sheath fixing jig is installed in the formwork, and then a jig for forming the sheath and inspection structure is installed. (b) is the state in which the formwork is filled with concrete. A sectional view showing a second embodiment of the inspection structure according to the present invention A sectional view showing a state in which a jig for forming an inspection structure according to a second embodiment is installed in a formwork. FIG. 3 is a cross-sectional view showing how the joint member is inserted into the inspection structure according to the first embodiment, in which (a) shows when the joint member is inserted the deepest within the permissible range, and (b) shows when the joint member is inserted relatively within the permissible range. When the amount of filling is small Cross-sectional view showing a state in which grout is filled between adjacent inspection structures and into inspection holes. Cross-sectional view showing the state in which grout is filled into the sheath and joint member after passing through the PC steel material A sectional view showing a third embodiment of the inspection structure according to the present invention A sectional view showing a state in which a jig for forming an inspection structure according to a third embodiment is installed in a formwork. FIGS. 3A and 3B are cross-sectional views showing how the joint member is inserted into the inspection structure according to the third embodiment, in which (a) shows the state when the joint member is inserted the deepest within the allowable range, and (b) shows the state when the joint member inserts the joint member the shallowest within the allowable range. (c) is when the insertion amount is insufficient (outside the allowable range) A sectional view showing a fourth embodiment of the inspection structure according to the present invention A sectional view showing a state in which a jig for forming an inspection structure according to a fourth embodiment is installed in a formwork. A sectional view showing a state in which the inspection structure forming jig according to the first modification is installed in the formwork. A sectional view showing a state in which a jig for forming an inspection structure according to a second modification is installed in a formwork. A sectional view showing a fifth embodiment of the inspection structure according to the present invention A sectional view showing a state in which a jig for forming an inspection structure according to a fifth embodiment is installed in a formwork. A sectional view showing a sixth embodiment of the inspection structure according to the present invention A sectional view showing a state in which a jig for forming an inspection structure according to a sixth embodiment is installed in a formwork.

A first embodiment (part of the whole) of an inspection structure 10 according to the present invention is shown in FIG. This inspection structure 10 is used for constructing concrete structures such as bridges and expressway viaduct deck slabs.

The main components of this inspection structure 10 include a main body 11, a hollow cylindrical sheath 12 embedded in the main body 11, and an inspection hole 13 that penetrates from the outer surface of the main body 11 to the surface of the sheath 12. There is.

The main body portion 11 is a rectangular parallelepiped-shaped member made of hardened concrete, and constitutes the outer contour of the inspection structure 10 . The size varies depending on the type and scale of the concrete structure, but for example, the width in the vertical direction (horizontal direction in Figure 1) and the horizontal direction (backward direction in Figure 1) is approximately several meters, and the thickness (as shown in Figure 1). (in the vertical direction) is often set from several tens of centimeters to about one meter.

The sheath 12 is a resin member that includes an insertion portion 15 into which a joint member 14 (described later) is inserted, and a spiral portion 16 that is continuous with the insertion portion 15 at both ends. The entire insertion portion 15 and spiral portion 16 are made of a transparent material that can transmit visible light (for example, general white illumination light), and in this embodiment, milky white translucent polyethylene is used. . This transparent material is not particularly limited in its type or transparency, as long as it allows the axial position of the joint member 14 inserted into the insertion portion 15 to be visually recognized, such as a transparent material or a translucent material.

The axial length of the transparent material visible through the inspection hole 13 corresponds to the width of the permissible axial insertion depth of the coupling member 14 . That is, when the allowable range of the insertion depth of the joint member 14 into the insertion portion 15 is 30 mm, the inspection hole 13 is formed so that its axial length is about 30 mm.

In this embodiment, the insertion portion 15 and the spiral portion 16 are entirely made of a transparent material, but only a portion thereof (for example, the upper half corresponding to the axial position of the inspection hole 13) is made of a transparent material. You can also.

The end of the insertion portion 15 is open through an opening 17 formed in the end surface of the main body portion 11 . When connecting the inspection structures 10 to each other, the opening 17 is axially continuous with the concave fitting step 18 facing the end surface of the adjacent inspection structures 10 and the fitting step 18 is connected to the main body 11. It has a diameter-reducing portion 19 which is a tapered surface whose inner diameter decreases as it goes deeper. The insertion portion 15 of the sheath 12 is connected to the smaller diameter end of the reduced diameter portion 19 . A convex fitting step 20 is formed in the opening 17 of the adjacent inspection structure 10 facing the concave fitting step 18 (see FIG. 7(a)). Both inspection structures 10, 10 are arranged so that the convex fitting step portion 20 slightly enters inside the inspection structure 18. In this way, shear resistance in the vertical direction is generated due to the fitting of the adjacent fitting steps 18 and 20, so that the connection strength between the inspection structures 10 can be increased. Although the present embodiment shows an example in which the fitting steps 18 and 20 are formed, a configuration in which the fitting steps 18 and 20 are not formed (a configuration in which the flat surfaces of adjacent inspection structures 10 face each other) is also possible. Good too.

The spiral portion 16 has a spiral projection formed over the entire length in the axial direction. Unlike the insertion portion 15, this spiral portion 16 is not limited to a transparent material or a translucent material, but may also be made of a metal material.

The inspection hole 13 extends to the outer surface of the portion of the insertion portion 15 made of a transparent material, and through this transparent material, the axial depth of the joint member 14 inserted into the insertion portion 15 (the presence or absence of the joint member 14) can be visually checked. Check by In this embodiment, the inspection hole 13 is a hole having a circular cross section with a constant inner diameter from the outer surface of the main body part 11 to the transparent material of the insertion part 15, but the shape of the hole is not particularly limited. , it can also have a rectangular cross section. Alternatively, the inspection hole 13 may be narrow at the top and widen at the bottom. In this case, the connection state of the joint member 14 can be easily inspected using a photographing means such as a fiberscope.

FIG. 2 shows an example of the joint member 14 inserted into the insertion portion 15. The joint member 14 includes a hose portion 21 and connecting portions 22, 22 connected to both ends of the hose portion 21. The hose portion 21 is a flexible resin member. The connecting portion 22 is a resin member having a predetermined rigidity to withstand connection with the sheath 12. A circumferential groove is formed in the outer circumferential surface near the axial end of the connecting portion 22, and an O-ring (hereinafter referred to with the same reference numeral as the seal member 23) as a seal member 23 is provided in this circumferential groove. ing. The O-ring 23 is made of a black colored rubber material. The O-ring 23 ensures liquid tightness between the coupling member 14 and the sheath 12. In order to ensure liquid tightness by the O-ring 23, the O-ring 23 is located axially inside the reduced diameter portion 19 formed in the main body portion 11, and connects the joint member 14 and the sheath 12 (insertion portion 15). It must be securely sandwiched between the two.

Since the O-ring 23 is colored black, it can be clearly seen through the inspection hole 13 and the transparent material of the insertion portion 15. Therefore, the insertion depth of the joint member 14 into the insertion portion 15 can be adjusted by sliding the joint member 14 in the axial direction as necessary within the range where the transparent material is provided.

In the above embodiment, the insertion portion 15 of the sheath 12 is made of a transparent material, and the connection portion 22 of the joint member 14 is inserted into the inner diameter side of the insertion portion 15. It is also possible to use a transparent material and insert the connecting part 22 into the outer diameter side of the insertion part 15. In this way, at least the member on the outer diameter side at the time of connection of the insertion portion 15 of the sheath 12 or the connection portion 22 of the joint member 14 may be made of a transparent material.

An example of the inspection structure forming jig 24 for forming the inspection hole 13 according to the first embodiment is shown in FIGS. 3(a) and 3(b). This inspection structure forming jig 24 includes a core 25 that forms an inspection hole 13 extending from the outside of the main body 11 made of hardened concrete to a hollow cylindrical sheath 12 buried in the main body 11, and a sheath 12. The main component is a fixing means 26 for fixing the core 25 to the core 25.

The core 25 is composed of a cylindrical outer cylinder 27, a pressed member 28, and a pressing member 29.

The outer tube 27 is a cylindrical member protruded from the surface of the sheath 12, and allows the outer surface of the hollow cylindrical sheath 12 embedded in the main body 11 to be seen from the outside of the main body 11. A side wall of the inspection hole 13 penetrating through is formed. In this embodiment, a cylinder is used as the outer cylinder 27, but a rectangular cylinder with a rectangular cross section may also be used. By keeping the lower end of the outer cylinder 27 in contact with the outer surface of the insertion portion 15 (transparent material) (see FIG. 4(a), etc.), the pressed member 28 pushed out by the pressing member 29 is held against the outer surface of the insertion portion 15 (transparent material). It can be attached smoothly.

The pressed member 28 is a foam (backup material) provided inside the outer tube 27 so as to face the insertion portion 15 of the sheath 12 . As this foam, for example, foamed urethane resin can be used. The pressed member 28 is not limited to foam, and may be made of a material that deforms when pressed and comes into close contact with the sheath 12, such as clay.

The pressing member 29 is a member for pressing the pressed member 28 toward the sheath 12. In this embodiment, a cylindrical member having an outer diameter slightly smaller than the inner diameter of the outer cylinder 27 is used as the pressing member 29. When the pressed member 28 is pressed by the pressing member 29, the pressed member 28 enters the gap between the outer cylinder 27 and the sheath 12, and the space between the pressed member 28 and the permeable material of the insertion portion 15 of the sheath 12 is The gap is closed and they stick together.

As shown in FIG. 3(a) etc., a band-shaped fixing means 26 is attached to the outer tube 27, the pressed member 28, and the pressing member 29 through the outer peripheral surface of the insertion portion 15 (sheath 12). A binding member 30 is wound around the binding member 30. When this binding member 30 is tightened, the pressing member 29 is pushed toward the pressed member 28 by the tightening force, and as shown in FIG. 3(b), the pressed member 28 is inserted into the insertion portion 15 (sheath 12). being pushed towards. Since this pressing member 29 has a cylindrical shape, a pressing force does not directly act on the center of the pressed member 28, but a large pressing force acts on its outer periphery. Therefore, the outer peripheral portion of the pressed member 28, which is separated from the surface of the insertion portion 15 (sheath 12) before pressing, can be smoothly brought into close contact with the surface of the insertion portion 15 (sheath 12). In this embodiment, a cylindrical member is used as the pressing member 29, but a cylindrical member may also be used.

An example of the manufacturing process of the inspection structure 10 according to the first embodiment will be described using FIGS. 4(a) and 4(b).

In this manufacturing process, first, the sheath fixing jig 32 is attached to the inner wall of the mold 31 for forming the inspection structure 10. As shown in FIG. 4(a), a stepped portion for forming a concave fitting stepped portion 18 (see FIG. 1) is formed at one end side of the formwork 31 (left end side in FIG. 4(a)). In order to form a reduced diameter part 19 (see FIG. 1) in the sheath fixing jig 32, which is continuous with the fitting stepped part 18 in the axial direction and whose inner diameter decreases toward the back of the main body part 11. A tapered portion is formed. Moreover, a step portion for forming a convex fitting step portion 20 (see FIG. 7(a)) is formed on the other end side (not shown) of the formwork 31.

The insertion portion 15 at one end of the sheath 12 is inserted into the end of the sheath fixing jig 32 on the reduced diameter side. A sheath fixing jig (not shown) is also inserted into the insertion portion (not shown) at the other end of the sheath 12 . As the material of the sheath fixing jig 32, polyvinyl chloride resin or metal can be used. In this embodiment, the sheath fixing jig 32 is hollow, but it can also be solid.

After both ends of the sheath 12 are fixed with the sheath fixing jig 32, a jig 24 for forming the inspection structure shown in FIG. 3(a) is attached to the insertion portion 15 of the sheath 12. Then, by tightening the binding member 30 and pressing the pressing member 29, the pressed member 28 is pressed toward the insertion portion 15 of the sheath 12, and the pressed member 28 and the transparent material of the insertion portion 15 of the sheath 12 are Close contact. Then, as shown in FIG. 4(b), the formwork 31 is filled with concrete 33. After the concrete 33 has hardened, the formwork 31, the sheath fixing jig 32, and the inspection structure forming jig 24 are removed to obtain the inspection structure 10 shown in FIG. 1.

In the inspection structure 10 according to the first embodiment, the axial length of the transparent material visually recognized through the inspection hole 13 corresponds to the width of the allowable range of the axial insertion depth of the joint member 14. Although the hole 13 is formed, the inspection hole 13 may be made to have a smaller diameter, as in the second embodiment shown in FIG. 5, for example, as long as the insertion state of the joint member 14 can be inspected.

FIG. 6 shows a state in which the inspection structure forming jig 24 according to the second embodiment is installed in the formwork 31. The core 25 of the inspection structure forming jig 24 is a bolt 34, and the fixing means 26 for the core 25 is a nut 35 fixed to the surface of the sheath 12 by adhesive or insert molding. The bolt 34 is screwed into the nut 35 until its tip abuts against the outer surface of the sheath 12 (insertion section 15). The formwork 31, and the sheath 12 and sheath fixing jig 32 provided in the formwork 31 are the same as those according to the first embodiment, so their description will be omitted (see FIG. 4(a)).

After filling the formwork 31 with concrete and hardening it, the formwork 31, sheath fixing jig 32, and bolts 34 are removed to obtain the inspection structure 10 shown in FIG. 5. Note that in order to easily remove the bolt 34, it is preferable to apply a lubricant such as grease to the shaft portion of the bolt 34. In addition, when filling the formwork 31 with concrete, a water-repellent material (for example, It is preferable to wrap a tape-shaped fluororesin and then screw it into the nut 35.

In this embodiment, the bolt 34 is used as the core 25, but a round steel having a threaded portion formed at the tip to be screwed into the nut 35 may also be used. Alternatively, a rod-shaped body may be employed as the core 25, and this rod-shaped body may be fixed to the sheath fixing jig 32 using a fixing means other than screws, such as an adhesive. In this case, the material of the rod-shaped body is not limited to steel, and any material such as a resin material can be used.

Further, it is also possible to employ a bolt 34 in which at least a portion of the shaft portion is formed in a tapered shape. By making the bolt 34 tapered in this manner, the bolt 34 can be smoothly removed after the concrete filled in the formwork 31 has hardened.

An example of the construction process of a concrete structure to which the inspection structure 10 according to the first embodiment is connected will be explained using FIGS. 7(a) and 7(b), FIG. 8, and FIG. 9.

First, as shown in FIG. 7(a), the connecting portion 22 of the joint member 14 is inserted into the insertion portion 15 of the sheath 12 of the inspection structures 10, 10 arranged adjacent to each other. Since the insertion portion 15 is made of a transparent material, the axial position of the O-ring 23 provided in the connection portion 22 can be visually inspected through the inspection hole 13 and the transparent material of the insertion portion 15. . The axial position of the O-ring 23 varies depending on the insertion depth of the connecting part 22 into the insertion part 15, as shown in FIG. 7(b), but as long as the O-ring 23 is visible through the inspection hole 13 and the transparent material In this case, the insertion depth can be determined to be appropriate.

Once the relative positions of the adjacent inspection structures 10, 10 are determined, grout 36 is filled between the two inspection structures 10, 10 and into the inspection hole 13, as shown in FIG. After the grout 36 hardens, a PC steel material 37 is inserted into the sheath 12 and tension is applied to the PC steel material 37 to introduce prestress (compressive stress) into the concrete structure in which the inspection structure 10 is integrated. Thereafter, as shown in FIG. 9, grout 38 for preventing corrosion of the PC steel material 37 is filled into the sheath 12 and the joint member 14 and hardened to complete the concrete structure.

The inspection structure 10 manufactured in this way can obtain various information such as not only the insertion state of the joint member 14 but also the filling state of the grout 38 in the sheath 12 through the inspection hole 13 and the transparent material of the sheath 12. This also contributes to the construction of high-quality concrete structures.

A third embodiment (part of the whole) of the inspection structure 10 according to the present invention is shown in FIG. The inspection structure 10 according to the third embodiment is similar to the inspection structure 10 according to the second embodiment (see FIG. 5), but the inspection hole 13 extends from the outer surface of the main body 11 to the sheath 12 (insertion section 15). ) is different in that it penetrates to the inside. In this way, by penetrating the inspection hole 13, the insertion depth of the joint member 14 inserted into the sheath 12 can be directly inspected, so that inspection work can be performed easily and reliably. Further, in this configuration, since the insertion portion 15 of the sheath 12 does not need to be made of a transparent material, a colored general-purpose sheath 12 can also be used.

FIG. 11 shows a state in which the inspection structure forming jig 24 according to the third embodiment is attached to the formwork 31. The core 25 of the inspection structure forming jig 24 is a bolt 34, and the fixing means 26 of the core 25 is a sheath fixing jig 32 that fixes the end of the sheath 12, and an insert in this sheath fixing jig 32. This is a nut 39 fixed by molding. The tip of the bolt 34 passes through the sheath 12 (insertion section 15) and is screwed into a nut 39 fixed to the sheath fixing jig 32.

There is no particular problem in forming a bolt hole in the sheath fixing jig 32 and directly screwing the bolt 34 into this bolt hole. By screwing in the sheath fixing jig 32, the durability of the sheath fixing jig 32 is further increased, so that the cost of members can be reduced. Since the formwork 31 and the sheath 12 are the same as those in the first embodiment, their explanation will be omitted (see FIG. 4(a)).

After filling the formwork 31 with concrete and hardening it, the formwork 31, sheath fixing jig 32, and bolts 34 are removed to obtain the inspection structure 10 shown in FIG. 10. Note that in order to easily remove the bolt 34, it is preferable to apply a lubricant such as grease to the shaft portion of the bolt 34. In addition, when the formwork 31 is filled with concrete, the sheath is fixed so that the paste component of the concrete does not enter the sheath 12 through the gap between the through hole formed in the sheath 12 and the sheath fixing jig 32. It is preferable to attach a sponge-like tape material (a liquid-tight member) between the jig 32 and the insertion portion 15 of the sheath 12.

FIGS. 12(a) to 12(c) show a state in which the joint member 14 is inserted into the inspection structure 10 according to the third embodiment. In this inspection structure 10, the inspection rod 40 is inserted into the inspection hole 13 with the joint member 14 inserted into the sheath 12, and the inspection rod 40 contacts the outer peripheral surface of the joint member 14 and is inserted into the sheath 12. If not, it is determined that the insertion depth of the joint member 14 is within the allowable range. Within this allowable range, the O-ring 23 provided on the coupling member 14 is inserted between the open end of the sheath 12 and the inspection hole 13 (between the position shown in FIG. 12(a) and the position shown in FIG. 12(b)). ) is located in Therefore, this O-ring 23 can ensure liquid tightness between the sheath 12 and the coupling member 14.

On the other hand, as shown in FIG. 12(c), when the inspection rod 40 inserted into the inspection hole 13 can be inserted into the sheath 12 without contacting the outer peripheral surface of the coupling member 14, It is determined that the insertion depth is outside the allowable range. Outside this allowable range, the O-ring 23 provided on the coupling member 14 is located outside the open end of the sheath 12. Therefore, the O-ring 23 cannot ensure liquid tightness between the sheath 12 and the coupling member 14.

The axial position of the O-ring 23 of the joint member 14 used in the inspection structure 10 according to the third embodiment is the same as the O-ring 23 of the joint member 14 (see FIG. 2) used in the inspection structure 10 according to the first embodiment etc. It is offset toward the center in the axial direction than the axial position of. By doing this, when the insertion depth of the joint member 14 is within the allowable range, the axial positions of the O-ring 23 and the inspection hole 13 are prevented from overlapping, and the liquid-tight action of the O-ring 23 is ensured. are doing.

In addition, in this embodiment, the insertion depth of the joint member 14 was inspected by inserting the inspection rod 40 into the inspection hole 13, but the inner diameter of the inspection hole 13 is large to some extent, and lighting with sufficient brightness is required at the work site. If this can be ensured, direct inspection may be possible visually without using the inspection rod 40.

A fourth embodiment (part of the whole) of the inspection structure 10 according to the present invention is shown in FIG. The inspection structure 10 according to the fourth embodiment is similar to the inspection structure 10 according to the third embodiment (see FIG. 10), but differs in that a tubular member 41 is provided on the inner wall of the inspection hole 13. For example, a rubber hose can be used as the tubular member 41. The lower end of this tubular member 41 is in contact with a sponge-like tape material (not shown) provided between the sheath fixing jig 32 and the insertion portion of the sheath 12. This contact further increases the liquid tightness between the through hole formed in the sheath 12 and the sheath fixing jig 32, so that when the formwork 31 is filled with concrete, the paste components of the concrete are contained in the sheath 12. Entry can be reliably prevented.

FIG. 14 shows a state in which the inspection structure forming jig 24 according to the fourth embodiment is attached to the formwork 31. The core 25 of the inspection structure forming jig 24 is a bolt 34, and the fixing means 26 for the core 25 is a sheath fixing jig 32 for fixing the end of the sheath 12. A tubular member 41 is attached to the shaft portion of the bolt 34 in advance. The tip of the bolt 34 passes through the sheath 12 (insertion section 15) and is screwed into a nut 39 fixed to the sheath fixing jig 32 by insert molding. Since the formwork 31 and the sheath 12 are the same as those in the first embodiment, their explanation will be omitted (see FIG. 4(a)).

Although the inspection structure forming jig 24 according to the third embodiment and the fourth embodiment uses a solid sheath fixing jig 32, as shown in FIG. A hollow sheath fixing jig 32 can also be employed as long as it has sufficient wall thickness (first modification). In this case, it is preferable to provide a nut 42 inside the sheath fixing jig 32 and fix the bolt 34 by sandwiching the inner and outer surfaces of the sheath fixing jig 32 between the nuts 35 and 42.

Further, although the inspection structure forming jig 24 according to the third embodiment and the fourth embodiment has a structure in which the bolt 34 is screwed to the sheath fixing jig 32 side, as shown in FIG. The tubular member 43 as the core 25 may be directly fixed by a fixing means such as welding in accordance with the position of the through hole formed in the insertion portion 15 (second modification). In this case, the insertion portion 15 of the sheath 12 functions as the fixing means 26 for the tubular member 43. In this way, the work for attaching the bolt 34 (see FIG. 11, etc.) as the core 25 to the sheath 12 at the work site becomes unnecessary, so that the number of work steps can be reduced.

A fifth embodiment (part of the whole) of the inspection structure 10 according to the present invention is shown in FIG. In each of the inspection structures 10 according to the first to fourth embodiments described above, the inspection hole 13 was formed corresponding to the position of the insertion portion 15 of the sheath 12, but in this fifth embodiment, the insertion portion An inspection hole 13 is formed corresponding to the position of the reduced diameter portion 19 of the main body portion 11 instead of the inspection hole 15 . Even if the inspection hole 13 is formed in the reduced diameter portion 19 in this way, it is difficult to insert the inspection rod 40 (see FIGS. 12(a) to 12(c)) into the inspection hole 13 or perform direct visual inspection. By doing so, the insertion depth of the joint member 14 can be easily checked.

FIG. 18 shows a state in which the inspection structure forming jig 24 according to the fifth embodiment is attached to the formwork 31. The core 25 of the inspection structure forming jig 24 is a bolt 34, and the fixing means 26 for the core 25 is a sheath fixing jig 32 for fixing the end of the sheath 12. The tip of the bolt 34 is screwed into a nut 39 fixed to the sheath fixing jig 32 by insert molding. Since the formwork 31 and the sheath 12 are the same as those in the first embodiment, their explanation will be omitted (see FIG. 4(a)).

Although the formation position of the inspection hole 13 is not particularly limited, it is preferable to form it near the insertion portion 15 of the sheath 12. For example, when the sheath 12 is made of a transparent material, an inspection hole is formed at the end of the insertion section 15, as in the sixth embodiment (part of the whole) of the inspection structure 10 according to the present invention shown in FIG. By forming the sheath 13 so that a portion thereof overlaps, it is possible to easily check whether the joint member 14 has been inserted up to the insertion portion 15, and to ensure liquid tightness between the sheath 12 and the joint member 14. can be secured.

FIG. 20 shows a state in which the inspection structure forming jig 24 according to the sixth embodiment is attached to the formwork 31. The core 25 of the inspection structure forming jig 24 is composed of a bolt 34 and a tubular member 44 coaxially inserted into the bolt 34. This tubular member 44 is a double tube composed of an inner member 44a and an outer member 44b. The fixing means 26 of the core 25 is a sheath fixing jig 32 that fixes the end of the sheath 12. A washer 45 and a nut 46 are coaxially provided on the bolt 34. The tip of the bolt 34 is screwed into a bolt hole formed in the sheath fixing jig 32. A counterbore is formed around this bolt hole, and the lower end of the inner member 44a is in contact with this counterbore.

When the bolt 34 is screwed into the sheath fixing jig 32, the inner member 44a is pressed against the bottom of the counterbore and the outer member 44b is pressed against the sheath fixing jig 32 and the end of the insertion section 15 through the washer 45 and nut 46. . This pressing increases the liquid tightness between the tubular member 44, the sheath fixing jig 32, and the sheath 12, and when the formwork 31 is filled with concrete, the concrete flows into the sheath 12 from the end of the insertion portion 15. It is possible to reliably prevent paste components from entering or adhering to the surface of the end portion of the insertion portion 15.

After filling the formwork 31 with concrete and hardening it, the formwork 31, sheath fixing jig 32, bolts 34, and tubular member 44 are all removed to obtain the inspection structure 10 shown in FIG. 19. Note that in order to easily remove the tubular member 44, it is preferable to apply a lubricant such as grease to the surface of the tubular member 44 (outer member 44b). In this embodiment, the tubular member 44 is a double pipe, but a single pipe may be used as long as its end can be reliably pressed against the counterbore or the end of the insertion portion 15. .

The inspection structure 10 and inspection structure formation jig 24 described above are examples in all respects, and the problem of the present invention is to easily grasp the insertion state of the coupling member 14 into the sheath 12. As long as the problem can be solved, changes can be made as appropriate to the shape and material of the inspection structure 10 and the jig 24 for forming the inspection structure.

10 Inspection structure 11 Main body part 12 Sheath 13 Inspection hole 14 Joint member 15 Insertion part 16 Spiral part 17 Opening part 18 (Concave) fitting step part 19 Diameter reduction part 20 (Convex) fitting step part 21 Hose part 22 Connection part 23 Seal member (O ring)
24 Inspection structure forming jig 25 Core 26 Fixing means 27 Outer cylinder 28 Pressed member 29 Pressing member 30 Binding member 31 Formwork 32 Sheath fixing jig 33 Concrete 34 Bolts 35, 39, 42, 46 Nuts 36, 38 Grout 37 PC steel material 40 Inspection rods 41, 43, 44 Tubular member 44a Inner member 44b Outer member 45 Washer

Claims (5)

a main body (11) made of hardened concrete;
a hollow cylindrical sheath (12) embedded within the main body (11) and having an insertion portion (15) that opens to the outside of the main body (11);
an inspection hole (13) for inspecting the presence or absence of the joint member (14) inserted into the insertion portion (15);
Equipped with
At least a portion of the sheath (12) is made of a transparent material that can transmit visible light;
The inspection hole (13) penetrates from the outer surface of the main body part (11) to the outer surface of the transparent material,
The axial length of the transparent material visually recognized through the inspection hole (13) is the allowable range of the axial insertion depth when the coupling member (14) is inserted into the insertion portion (15). It corresponds to the width of
An inspection structure (10) including a seal member (23) provided at an axial end of the joint member (14) to ensure liquid tightness between the joint member (14) and the sheath (12). use,
The connecting portion (22) of the coupling member (14) is inserted into the insertion portion (15) of the sheath (12) of the inspection structures (10, 10) arranged adjacent to each other, and the inspection hole ( 13) and the permeable material of the insertion portion (15), visually inspect the axial position of the seal member (23) provided in the connection portion (22), and check the inspection hole (13) and the An inspection method for determining that the insertion depth of the joint member (14) is appropriate when the seal member (23) is visible through a transparent material. a main body (11) made of hardened concrete;
a hollow cylindrical sheath (12) embedded within the main body (11) and having an insertion portion (15) that opens to the outside of the main body (11);
an inspection hole (13) for inspecting the presence or absence of a joint member (14) inserted into the insertion portion (15);
Equipped with
Using an inspection structure (10) in which the inspection hole (13) penetrates from the outer surface of the main body (11) to the inside of the sheath (12),
The inspection rod (40) is inserted into the inspection hole (13) with the coupling member (14) inserted into the sheath (12), and the inspection rod (40) is inserted into the outer peripheral surface of the coupling member (14). An inspection method for determining that the insertion depth of the joint member (14) is within an allowable range when the joint member (14) cannot be inserted into the sheath (12) due to contact with the joint member (14). An inspection hole for checking the presence or absence of a joint member (14) inserted into a hollow cylindrical sheath (12) buried in the main body (11) from the outside of the main body (11) made of hardened concrete. a core (25) forming (13);
fixing means (26) for fixing the core (25) at a predetermined position relative to the sheath (12);
A jig for forming an inspection structure. The core (25) is provided inside a cylindrical outer tube (27) protruding from the surface of the sheath (12) and the outer tube (27) so as to face the sheath (12). a pressed member (28), and a pressing member (29) that presses the pressed member (28) toward the sheath (12);
The fixing means (26) passes through the outer peripheral surface of the sheath (12) and wraps around the outer cylinder (27), the pressed member (28), and the pressing member (29). 30), wherein the pressing member (29) is pushed toward the pressed member (28) by the tightening force of the binding member (30). Ingredients. A sheath fixing jig (32) is attached to the inner wall of a formwork (31) for forming the inspection structure (10), and an insertion portion for the end of the sheath (12) is attached to the end of the sheath fixing jig (32). (15) a step of inserting;
a step of attaching an inspection structure forming jig (24) according to claim 3 or 4 to the insertion portion (15) of the sheath (12);
The formwork (31) is filled with concrete (33), and after the concrete (33) has hardened, the formwork (31), the sheath fixing jig (32), and a jig for forming the inspection structure are filled. a step of removing the tool (24);
A method for manufacturing an inspection structure having

Images