JPS6027325B2 - Underwater concrete pouring method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an underwater concrete casting method that can suitably form a concrete layer on soft ground such as underwater sludge or uneven ground.

(Prior art) Conventionally, this type of concrete casting method has been disclosed in Japanese Patent Publication No. 43-6495 and Japanese Patent Publication No. 45-2.
There is a method as described in Japanese Patent No. 3796.

In other words, these conventional methods involve laying a cloth made by connecting a large number of long cylindrical bodies in parallel on the ground where concrete is to be placed, and then filling each cylindrical body with concrete one after another. be. (Problems to be Solved by the Invention) However, with the above conventional means, it is very difficult to sink the cloth into water for filling with concrete, and the work cannot be done quickly and accurately, especially in rivers. Or, in places where concrete is being placed in areas with rapid water or tidal currents, such as on the coast, the cloth may be washed away by the water current, making it impossible to accurately sink and send it to the designated position. However, this method had a major problem in that it required the use of separate positioning and fixing stakes to secure the curtain.

In addition, in the conventional means, since the cloth ridge for filling concrete is formed by simply installing a cylindrical body, the top surface of the cloth ridge is formed when the concrete is filled. The fabric has irregularities, making it extremely difficult to form a smooth surface suitable for the foundation of a building, etc., and the outer shape of the side of the cloth corner also becomes disorderly. There was also a problem in that it was not possible to arrange them adjacent to each other in an orderly manner.

As described above, since the above-mentioned sub-concrete means used for pouring concrete using a cylindrical body mounted on a cross-section, it had various problems as mentioned above.

The present invention was invented to solve the above-mentioned conventional problems, and its purpose is to accurately and quickly lay the concrete filling material on the underwater ground, thereby improving the workability. The purpose of this invention is to make the concrete casting surface suitable for building foundations and the like.

(Means for Solving the Problems) The present invention is constructed to achieve the above objects and solve the problems of the conventional art. The bag body 2, which has an inlet entrance 3 and a frame body 5 on the outer circumferential side, is lowered by the weight of the frame body 5 onto the upper surface of soft ground under water, etc. Then, the bag body 2 is filled with concrete and hardened using a concrete pouring machine.

(Function) That is, in the concrete pouring method characterized by the above structure, in order to sink the bag 2 for filling with concrete by its own weight, the bag 2 is placed on the ground. All the work is to do is to drop the bag 2 above a predetermined position, and the bag 2 can easily be washed away even in places where there is a rapid flow of water, causing the bag to shift position. do not have.

Furthermore, since the bag 2 is constructed as a single unit and has a frame 5 provided on its outer periphery, when the bag 2 is filled with concrete, the top surface is smooth and the outer circumference shape is shaped like the frame 5 in advance. This results in a concrete layer that is molded using the same method. (Example) Hereinafter, embodiments of the present invention will be described according to an example shown in the drawings.

That is, when forming a concrete layer on soft ground 1 made of sludge or the like, first, as shown in FIG. 1, a waterproof bag 2 made of chemical fibers and made of, for example, five skins on four sides is prepared in advance.

The bag body 2 has a large number of small holes 4 for water passage in the vertical direction, a closing part 3 for concrete inflow in the upper surface, and is attached to an iron frame 5 on the outer periphery. . Next, when a large number of these bags 2 are sunk in a predetermined position from the sea, the frame 5 acts as a weight and the bags 2 naturally sink and are rebuilt on the soft ground 1 (see Figure 3). The bag body 2 will not be washed away by water current or the like. After the bag body 2 is placed on the soft ground 1 in this way, the tip of the transport pipe 7 of the concrete pump 6 installed on the ship is connected to the entrance part 3 of the bag body 2 in the water as shown in FIG. When the pump 6 is driven in this state, the concrete material is pumped through the transport pipe 7 by its gravity and flows into the bag body 2 from the opening 3.

At that time, a large number of small holes 4 for water passage are bored in the bag body 2, but since the small holes 4 are minute holes 4 through which concrete materials such as aggregate hardly flow, some of the water flows out. However, this has almost no effect on the formation of the concrete layer.

In addition, since the bag body 2 is provided with a frame body 5 on its outer peripheral side, the shape of the outer peripheral side part is a shape pre-formed by the frame body 5, and a plurality of bags 2 are arranged between them. They can be placed adjacent to each other without creating any gaps, and furthermore, the concrete filled in the bag 2 has a smooth upper surface and hardens to form the concrete layer 8.

When the concrete layer 8 is formed inside each bag body 2 in this way, a flat concrete surface with no unevenness is formed on the soft ground 1 as shown in FIG. It can be used as the foundation for building structures without any subsidence. Furthermore, Figure 6 shows an example of fixing sheet piles using this construction method.
When the sheet pile 9 was driven into the ground, the embedded portion 9a of the sheet pile 9 was driven into the soft ground 1, so the stability was extremely poor and there was a risk of it shaking.

In order to solve this problem, as shown in the same figure, the bag 2 is lowered onto the soft ground 1 on both sides of the sheet pile 9, and the concrete IJ material is poured into it using the method described above to harden it. .
When the concrete material hardens within the bag body 2 in this way, the concrete layer 8 supports the sheet pile 9 on both sides, so that although the embedded portion 9a is driven into the soft ground 1, it never swings. It has a stabilizing effect. Therefore, the conventional work of pulling the sheet piles 9 with ropes from each direction to support them is no longer necessary. Further, by forming the bags 2 in an L-shape on both sides of the sheet pile 9 and hardening the concrete material, the supporting force is further strengthened. In the above embodiment, a concrete layer is formed using a bag in surface contact on relatively flat soft ground 1, but as shown in FIG. In the case of forming a concrete layer, a bag body 2a made of an elastic material whose bottom surface is deformed along its uneven surface when concrete material flows in is prepared, and the concrete material is applied to the bag body 2a by the method described above. When poured, the concrete layer 8 is formed with the bottom surface of the bag body 2a deformed along the shape of the uneven ground la as shown in the figure, and the top surface is flat, so that the construction foundation will not settle unevenly due to masonry etc. The whole can be formed uniformly.

Further, the shape of the bag is not limited to the above-mentioned embodiments, and any shape may be used as long as it applies heavy pressure to the ground without uneven settling.

In addition to the bag having a regular shape, the material may be of an irregular shape made of an elastic member that deforms along the shape of the ground as the material flows in, and is not limited in any way. In addition, the small holes drilled in the bag should preferably have a size that prevents a large amount of aggregate, etc. in the concrete material from flowing out.
The specific structure of the other frame bodies can also be changed in design. Further, in the above embodiment, the concrete material is fed into the bag by gravity, but it may also be forced to be fed into the tube by compressed air.

In addition, even better effects can be obtained by using hydraulic cement such as boltland cement as the concrete material to be filled into the bag, and by mixing particles such as aluminum into the concrete material. This has the advantage that the distribution of the concrete material within the bag becomes uniform, making it easier to form a concrete layer that conforms to the shape of the bag. Further, in this embodiment, the object filled with concrete is called a bag, but the name may also be a container or the like. (Effects of the Invention) As described above, the present invention allows the bag to be filled with concrete to sink naturally onto the submerged ground due to the weight of the frame. This can be done quickly using the extremely simple method of rinsing, and since the frame itself acts as a weight, the bag will not be washed away by the water current as would be the case with a retainer, and as a result, it can be carried out quickly, which was difficult to do in the past. Even in places with rapid currents such as rivers and coasts, where the bag body is placed in a predetermined position accurately, concrete can be placed reliably, which is a special effect.

In addition, in order to fill concrete into a bag having a frame on the outer peripheral side, the present invention specifies the outer peripheral shape of the bag in advance, and when a plurality of bags are arranged adjacently in parallel, there is a gap between the bags. The bags can be placed adjacent to each other without creating any gaps, and furthermore, the bags can be formed as a single piece and can be filled with concrete with a smooth top surface, making it possible to create foundations for buildings that do not have uneven top surfaces as in the past. It has the effect of making it possible to construct the most suitable concrete foundation.

As described above, the present invention uses a bag provided with a frame as a member for concrete filling, allows the bag to sink naturally under the weight of the frame, and forms the bag using the frame. It has been created based on a completely new technical concept, and has the advantage of being able to easily fix sheet piles, etc., and has great practical value.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a bag according to the present invention. FIG. 2 is a longitudinal sectional view taken along line A-A. 3 and 4 are process diagrams of the construction method according to the present invention. Figure 5 is a cross-sectional view after concrete pouring. FIG. 6 and FIG. 7 are cross-sectional views showing the pond embodiment. 2...
... Bag body, 3 ... Sekiguchi part, 4 ... Small hole for quick water, 5 ... Frame body. Figure 1 Figure 2 Figure 3 Figure 7 Figure 7 Mountain vertical view ■ Ship

Claims (1)

[Claims] 1. A bag body 2 having a large number of small holes 4 for water passage and an opening 3 for concrete inflow, and a frame body 5 provided on the outer circumferential side, is placed on soft ground under water, etc. An underwater concrete pouring method characterized in that the frame body 5 is placed on the upper surface so as to sink under its own weight, and concrete is filled and hardened into the bag body 2 using a concrete pouring machine from the ground or on ice. . 2. The underwater concrete pouring method according to claim 1, wherein the bag body 2 is made of an elastic member that can be deformed along the shape of the ground.