JPH10102790A - Repairing method of periphery of concrete structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the period of time for repairing and to simplify it by burying steel pipes furnished with check valves, water stop plates, etc. with specified intervals at the time of depositing batholith concrete and injecting a grout material through the steel pipes in the case when a void is produced below a batholith. SOLUTION: Short pipes 5 of vinyl chloride pipes, etc., are buried with specified intervals (for example, 5m pitch) at the time of laying macadams 7 on a pile foundation and depositing conditioning concrete 8 on them. Batholith concrete 9 is deposited after erecting a steel pipe 1 furnished with a water expansible water stop material 3, a water stop plate 4 serving both as an anchor, a check valve 2, etc., on these short pipes and arranging normal reinforcement. Thereafter, drilling of a grout injection hole at the time of repairing is eliminated by injecting a grout material by removing a plug 10 and connecting an injection pipe in the case when a void is produced between a concrete structure and a peripheral ground below the concrete structure after a long period of time passes, support force is lowered and repairing is required. Consequently, it is possible to inject grout easily even when a working surface is narrow.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a repair method for repairing a decrease in the bearing capacity of the surrounding ground under a concrete structure after construction by injecting grout material.

[0002]

2. Description of the Related Art In a concrete structure constructed on a pile foundation provided on soft ground, the tip of the foundation pile itself is set in the supporting ground and does not sink, but the surrounding ground is subject to consolidation settlement. As a result, a gap is formed between the lower surface of the concrete structure and the ground, and the gap increases with time. A similar phenomenon occurs between the outer wall of the concrete structure and the outer peripheral ground. If this phenomenon is left unattended, the pile may be damaged if horizontal force is applied to the pile head due to an earthquake or the like.

[0003] Therefore, it is common practice to periodically inspect the lower part of the concrete structure, the surrounding ground and the gap, and if the gap is large, repair by filling and filling the gap with a grout material.

[0004]

When the grout material is injected and filled, a construction machine is carried into the floor of the lowest floor of the concrete structure to form an injection hole in the bottom slab concrete, and sometimes also in the outer wall concrete. Although it is necessary to inject and fill from the injection hole, the lowest floor is usually used as a machine room or an electric room, etc., and is often narrow and the equipment is congested, and the drilling work is often difficult. . In extreme cases, work may not be possible.

Therefore, a large-scale machine is not required,
There is a demand for a method capable of easily forming an injection hole even in a narrow work space.

[0006]

The invention according to claim 1 of the present application is characterized in that (A) a circular pipe provided with a check valve in the pipe and a water-swellable water-stop material on the outer periphery of the pipe is passed through concrete. The concrete structure is buried to form a bottom slab of the concrete structure, and (B) when a gap is formed in the ground below the bottom slab, a grout material is injected into the gap in the ground through the circular pipe. Peripheral repair method.

According to the present invention, instead of drilling an injection hole in the bottom slab concrete by boring at the time of repair, a circular pipe corresponding to the injection hole is buried at the time of construction of the bottom slab concrete, and this circular pipe is used as an injection hole at the time of repair. The object of the present invention is to solve the above-mentioned problem by making the use of the injection hole unnecessary at the time of repair.

As described above, in soft ground, not only a gap may be formed below the bottom slab, but also a gap may be formed between the underground portion of the outer wall and the surrounding ground. In that case, a circular pipe corresponding to the injection hole is buried at the time of construction in the outer wall concrete of the underground part, similarly to the bottom slab concrete. This case is the invention according to claim 2.

In the case of the buried circular pipe, not only when the bottom slab is constructed below the groundwater level, but also when the bottom slab is constructed above the groundwater level, a check is made in the pipe in consideration of the rise of the groundwater level. A valve is installed to prevent the inflow of groundwater, and a water-swellable water-stopping material is installed around the pipe to prevent the inflow of groundwater from the boundary between the circular pipe and concrete. It is preferable to mount a disc-shaped water-stop plate on the outer periphery of the pipe, which also serves as an anchor, at a location different from the water-swellable water-stop material.

When the circular pipe is buried in the underground part of the outer wall, it is usually buried horizontally, but it may be inclined so that the indoor side is slightly higher. The inside surface of the buried circular pipe is covered with a lid, and is flush with the floor surface and the wall surface.

At the time of repair, when pouring the grout material with the circular pipe as the pouring hole, the lid is removed and the pouring pipe or the pouring hose is connected to the circular pipe. If the groundwater level is low and there is no concern about groundwater inflow, it is easier to inject if the check valve is removed before injecting. If removed, re-attach after injection.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention including a construction procedure will be described by taking as an example a case where a circular pipe corresponding to an injection hole is buried in bottom slab concrete at the time of construction of a bottom slab.

FIG. 1 is a longitudinal sectional view of a bottom slab concrete in which a circular pipe is buried.

A crushed stone 7 is laid on a pile foundation, and a leveling concrete 8 is poured thereon. At this time, short cylindrical bodies 5 such as a PVC pipe for installing the circular pipe 1 are embedded at predetermined intervals (for example, at a pitch of about 5 m). A water-swellable water-stop material 3 is adhered to a lower outer periphery of the circular pipe 1 which is a steel pipe, and a disc-shaped steel plate is welded to a central outer periphery as a water-stop plate 4 also serving as an anchor. Is the check valve 2 with socket 6 and plug 1
0 attached. The plug 10 serves as both the attachment of the check valve 2 to the circular tube 1 and the lid of the circular tube 1, and is screwed into the socket 6. The circular pipe 1 is set up in the short cylindrical body 5, and the reinforcing bars and the formwork are assembled in the usual manner, and the bottom slab concrete 9 is driven to the upper surface level of the plug 10. A bottom slab with a floor flush with the upper end surface of the circular tube 1 is constructed, and the circular tube 1 whose upper end is covered with a plug 10 at predetermined intervals is buried in the slab concrete 9 through the bottom slab concrete 9. I have.

Although not shown, when burying the circular pipe 1 in the underground part of the outer wall, the circular pipe 1 similar to the above is arranged together with the reinforcing bar in the formwork for constructing the outer wall, and the outer wall concrete is cast. I do.

A long time has passed since the construction of the concrete structure,
As a result of the void investigation, when it is determined that a void is generated between the ground and the surrounding ground and repair is required, the plug 10 at the end of the circular pipe 1 is removed, connected to the injection pipe, and the grout material is passed through the circular pipe 1. inject.

[0017]

The present invention has the above configuration and has the following effects.

(1) Since a circular pipe corresponding to the grout material injection hole is previously buried in the bottom slab concrete, sometimes the bottom slab concrete and the underground portion of the outer wall concrete, it is unnecessary to drill the injection hole at the time of repair. Even if the floor is narrow, grout can be easily injected and repaired.

(2) Since the circular pipe corresponding to the injection hole is provided with a check valve and a water-stopping material, groundwater does not flow into the bottom plate even if the bottom plate position is below the groundwater level.

(3) Since the circular pipe has excellent corrosion resistance and can be used semipermanently as an injection hole, it can easily cope with repair after a long period of time.

(4) Since the injection hole of a fixed shape is secured by the circular pipe, the range of the usable grout material is wide.

In summary of the above, it is possible to perform repairs in a short period of time when necessary and at low construction cost.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a bottom slab concrete in which a circular pipe is embedded.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Circular pipe, 2 ... Check valve, 3 ... Water-swellable water-stop material, 4 ... Water-stop plate, 5 ... Cylindrical body, 6 ... Socket, 7 ... Crushed stone, 8 ... Leveling concrete, 9 ... Bottom concrete, 10 ... Plug.

Claims (3)

[Claims] (A) A bottom pipe of a concrete structure is constructed by burying a circular pipe provided with a check valve in the pipe and having a water-swellable water-stop material on the outer periphery of the pipe by penetrating concrete, and (B) A) a method of repairing the periphery of a concrete structure, wherein when a gap is formed in the ground below the bottom slab, grout is injected into the gap of the ground through the circular pipe; 2. (A) A circular pipe provided with a check valve in the pipe and provided with a water-swellable water-blocking material on the outer periphery of the pipe is pierced through concrete and buried to construct a bottom plate of the concrete structure and an underground portion of the outer wall. And (B) a method of repairing the periphery of a concrete structure, characterized by injecting a grout material into the space in the ground through the circular pipe when a space is formed in the surrounding ground below the concrete structure. 3. The concrete according to claim 1, wherein the circular pipe further comprises a water stop plate on the outer periphery of the pipe in addition to the check valve and the water-swellable water-stopping material. Repair method around the structure.