JPS6242120B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an air bag that can be used as a partition or closure or as a supporting member in civil engineering works such as tunnel construction, large-diameter foundation hole construction, and underground continuous wall construction. .

Air bags are used as partition members when pouring concrete peripheral walls in horizontal holes such as foundation holes and tunnels, and when pouring continuous underground walls.

Conventional air bags consist only of a linear cylindrical bag body formed by laminating sheets made of base fabric and rubber or resin film, and the bag body is inserted between the excavated soil surface or the segment and the formwork. However, it was only enough to inflate it to fill the gap by forcing air into it. This kind of air bag has no support of its own, so when it is inflated between the excavated soil surface and a hard object such as formwork, if an external pressure greater than the inflation pressure is applied, the excavation Since the resistance on the soil surface side is small, it cannot support external pressure, and the pressure contact part of the bag body may become deformed or dislodged, resulting in loss of support and watertightness.

This invention eliminates the above-mentioned conventional drawbacks by providing an abutment plate for support on the air bag itself, and also provides the abutment plate intermittently, thereby ensuring the air bag's curvature and bending. In addition, it is an object of the present invention to provide an air bag for civil engineering work whose watertightness is further improved by a sealing material provided between abutting plates.

The present invention will be explained in detail below using illustrated examples.

1 is an air bag, and the bag body 2 is formed by laminating multiple sheets of durable synthetic rubber cloth of the required length.
and reinforcing covers 3, 4 made of rubberized cloth or the like applied to the outside of the bag body 2. In addition, on one side of the bag body 2, a required number of back plates 5, 5, etc. made of plywood or elastic cloth-filled synthetic rubber plates are provided.
... are intermittently pasted in the longitudinal direction at intervals, and the reinforcing cover 4 is applied to cover the contact plates 5, 5....

Further, between each contact plate 5, 5..., a sealing material 6 made of synthetic rubber or the like and having a trapezoidal cross section is buried downward from above the reinforcing cover 5, and the sealing material 6 is intermittently provided. By means of the contact plates 5, 5..., the bag body 2 can be curved to match the curvature of the opening end of the concrete casting part of the large-diameter foundation hole, and the abutment plates by the sealing material 6 can also be bent. By complementing each other's gaps, even if the curvature changes to some extent, it is possible to prevent concrete from leaking or flowing out from the gaps.

Note that 7 is an air inlet, which is attached to the end of the bag body 2.

Next, an example of the use of the air bag will be explained with reference to FIGS. 4 and 5.

First, the air bag 1 is flattened and inserted into the gap 13 between a horizontal hole 11 excavated underground and a formwork 12 built in the horizontal hole. The illustrated example is a case where a gap 13 is partitioned by two air bags 1, 1, and the formwork 12 is placed with the contact plates 5, 5 facing the excavation surface.
, and pull out the air inlet 7 into the horizontal hole.

When the above preparations are completed, connect the compressor hose to the air inlet 7, pressurize air into the bag body 2, expand it with air pressure, pressurize it outward, and apply appropriate surface pressure to the back plate 5, 5... and the sealing material 6 are brought into close contact with the excavated surface 11a, and the opposite surface is brought into close contact with the formwork 12. As a result, the gap 13
are partitioned without any gaps by the inflated air bag 1, and the air bag itself is pressurized outward by the air pressure to withstand external pressure.

Therefore, even if fresh concrete is press-fitted into the gap 13, the air bag 1 will not be deformed by the pressure, completely preventing concrete from leaking or flowing out.

Further, after the fresh concrete has solidified, the air in the air bag 1 may be allowed to flow out to the outside, and the air bag 1 can be deflated and easily removed.

As shown in FIG. 6, the air bag 1 has the following features:
It can also be used as a support member for a cylindrical body for preventing landslides in foundation holes. In this case as well, the air bag 1 is inserted with the contact plates 5, 5 facing toward the excavation surface.

In the above examples, the air bag 1 is curved in an arc along the soil surface of an excavated hole. 5 is pressed against the soil surface, it can be widely used as an air bag for civil engineering work.

As described above, this invention includes an arbitrary number of contact plates 5, 5 intermittently attached in the longitudinal direction of the bag body 2,
Since the contact plates 5, 5 are used to oppose the external force applied to the inflated bag body 2, it is resistant to external pressure compared to a case where the bag body only consists of the bag body, and provides support to the excavated soil surface. At the very least, the contact plate supports the excavated soil surface side by crimping, and the air bag is unlikely to shift or deform due to external pressure. Moreover, since each contact plate is attached intermittently, it has the advantage that the air bag can be deformed according to the shape of the excavated soil surface side or the formwork, etc., without interfering with the curvature of the bag body. Since there is a sealing material between each contact plate, watertightness is ensured even if each contact plate is intermittently installed, and leakage and outflow of poured concrete can be completely prevented. It has characteristics.

[Brief explanation of the drawing]

The drawings show one embodiment of the air bag for civil engineering construction according to the present invention, and FIG. 1 is a partially cutaway plan view, FIG. 2 is a cross-sectional front view of the air bag, and FIG.
Figure 3 is a vertical side view, Figure 4 is a vertical cross-section of the concrete poured area with the open end closed, Figure 5 is a front view, and Figure 6 is used as a support for landslide prevention materials. FIG. 1... Air bag, 2... Bag body, 3,
4... Reinforcement cover, 5... Contact plate, 6... Sealing material.

Claims (1)

[Claims] 1 An air bag of a required length used as a partition or closing member for holes or trenches excavated underground, or as a support member, with any number of abutments intermittently attached in the longitudinal direction of the bag body. An air bag for civil engineering work, characterized by having plates and an elastic sealing material between the contact plates.