JPH108457A - Core linked body used for underground wall and method of building core - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a core material for an underground wall and a method for installing the core material, which can be built with good accuracy without being twisted at the time of building. SOLUTION: A plurality of core members 11, 12, 21, 22, 31, 32 arranged substantially in parallel at predetermined intervals, and connection members 13a, 23a, 23b, which integrally connect the plurality of core members.
33a, whereby the plurality of cores can be simultaneously built in the ground.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a core used for an underground wall and a method for installing the core.

[0002]

2. Description of the Related Art A conventional underground wall, for example, a soil cement column wall as a retaining wall or a water blocking wall is formed by injecting a cement-based injection liquid into the ground from the tip of a mixing device.
The soil cement column was formed by stirring and mixing with the in-situ soil, and a core material such as a steel frame or a steel sheet pile was erected one by one before the soil cement column hardened.

[0003]

In the above-mentioned soil cement column walls, the dimensions of the core material and the interval between the core materials have conventionally been designed according to the magnitude of the bending stress near the floor. However, when the groundwater level is relatively low, as shown in the design lateral pressure map of Fig. 4 as -5.5m, or when the surface layer is a high-quality cohesive soil such as a loam layer, Is significantly lower than that near the floor. Therefore, as shown in the core material layout diagram of FIG. 4, it is ideal if the space between the core materials is larger than the predetermined depth and the space between the core materials is narrower below the predetermined depth, so that the design is ideal. That is, in the core material layout diagram of FIG.
The long core 52 and the short core 51 having a length of 10,000 mm are alternately arranged, and the upper end of the long core 52 is located on the ground surface, and the upper end of the short core 51 is 5,000 below the ground surface. mm, which allows for a core spacing of 9 mm above a depth of 5,000 mm.
00mm, core spacing 450 below 5,000mm depth
It is designed to be mm.

However, even if the underground wall is designed by allocating the long and short core members as described above, it is very difficult to construct such a soil cement column wall, and the following problems occur. When the core material is erected below the ground surface, it is difficult to grasp an error from the design position of the top end of the core material, and the possibility that the core material is twisted and inserted increases. As a result, the installation accuracy is reduced, and the distance between the core materials is increased by twisting, so that cracks are formed in the soil cement column walls, and water leaks between the core materials are likely to occur.

The present invention has been made to solve the above-mentioned drawbacks of the prior art and to solve the problem. The purpose of the present invention is to make it possible to arrange a core material in a desired layout and to twist the core material at the time of installation. It is an object of the present invention to provide a core material for an underground wall and a method of installing the core material, which can be built with good accuracy without being damaged.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned object, and the gist of the present invention is to integrate a plurality of core members arranged substantially in parallel at a predetermined interval with the plurality of core members. And a connecting member for connecting the plurality of cores so that the plurality of cores can be simultaneously built in the ground.

Another gist of the present invention is that a plurality of core members are arranged substantially in parallel at predetermined intervals, and the plurality of core members are integrally connected to form a core member connected body. There is a method of building a core material to be built in the ground after being lifted.

Another aspect of the present invention is that a plurality of core members having two or more types of lengths are arranged substantially in parallel at predetermined intervals, and the plurality of core members are integrally connected to form a connected core member. And a method of building a core material to be buried in the ground after lifting the connected core material, wherein a short core material of the plurality of core materials is ground when forming the connected core material. There is provided a method of building a core material, wherein the core material is arranged so as to be located in a section having a large earth pressure. Here, when the length of the core material is three or more types, the shortest core material is allocated to the underground section having the highest earth pressure, and the next short core material is assigned to the underground section having the next highest earth pressure. After allocating and sequentially arranging the core materials in the same manner, a connected core material is formed.

In the method for assembling the core material and the core material according to the present invention, the plurality of core materials may be formed in a plurality of kinds of lengths and arranged in a suitable order and substantially parallel to each other. For example,
A plurality of cores are used as two types of cores, a long core and a short core, and the long and short cores are alternately arranged, and the lower ends thereof are aligned at substantially the same position. The core material link is formed so that the long core materials are adjacent to each other and the core material interval is large, and below this, the long core material and the short core material are adjacent and the core material interval is dense. Can be. In short, by using core materials of different lengths of appropriate types, according to the soil pressure and ground pressure distribution depending on the soil quality and groundwater level of the ground, etc., the core materials are allocated so as to be dense or sparse. What is necessary is just to form a core material connection body.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments will be described below with reference to the accompanying drawings, but the present invention is not limited to these embodiments. Fig. 1 (a)
FIGS. 2A to 2C are front views showing the connected core material of the present invention, and FIG.
FIG. 2 is a sectional view taken along the line II-II of FIG. 1 (b), and FIG. 3 is a perspective view when the connected core material of the present invention is lifted.

Referring to FIG. 1 (a), a core material connected body 1 according to the present invention is shown.
Reference numeral 0 denotes one short core 11 made of I-shaped steel and one long core 12 made of I-shaped steel longer than the short core 11.
Are arranged substantially in parallel at equal intervals, and these short core materials 11
And the long core material 12 are connected to each other by a back side flat bar 13a and a skeleton side flat bar (not shown).
Further, in FIG. 1 (b), the core material connecting body 20 of the present invention
One short core 21 made of a shaped steel is
The two long cores 22 made of I-shaped steel longer than each other are arranged almost in parallel at equal intervals, and these short cores 21 are formed.
And the long core members 22, 22 are connected to the back side flat bar 23a.
And it connects and is formed by the frame side flat bar 23b. Further, in FIG. 1 (c), the core material connected body 30 of the present invention
Two short core members 31, 31 made of shaped steel, and two long core members 32, made of I-shaped steel longer than the short core material 31.
32 are arranged alternately and substantially in parallel at equal intervals, and these short core members 31, 31 and long core members 32, 32 are connected by a back side flat bar 33a and a frame side flat bar (not shown). Formed.

As shown in FIG. 1 (c), in the core connecting member 30, short cores 31, 31 and long cores 32,
Numerals 32 are arranged so that the positions of the ends (the ends that become the lower ends when built) are aligned. As a result, in the section A on the other end side (the end that becomes the upper end at the time of building), a section where the long cores 32 and 32 are adjacent to each other and there is no short core 31 and the core density is low is formed. You. Similarly, also in the core material connected bodies 10 and 20, one end is arranged at the same position, and a section having a low core material density is formed on the other end side. Sections with dense cores formed in this way are allocated to sections with high earth pressure when built in the ground, and sections with sparse cores are allocated with soil pressure when built in the ground. Assign to a small section.

As shown in FIG. 2, the back flat bar 23a in the core material linking body 20
2 (core member 22) is formed to have a length that can be continuously extended, and the skeleton side flat bar 23b is formed to have a length that can connect the flanges of the adjacent I-shaped steel 22. Then, the rear side flat bar 23a is welded to the outside of the flange of the I-shaped steel 22, and the skeleton side flat bar 23b is welded to the inside of the flange of the I-shaped steel 22. The flat bar on the back side and the flat bar on the skeleton side are arranged in the same manner in the core material linked bodies 10 and 30. By arranging the rear side flat bar outside the flange in this way, it is possible to satisfactorily counter the earth pressure from the back side to the skeleton side, and by arranging the skeleton side flat bar inside the flange, It is possible to give a margin to the clearance between the skeleton.

[0014] Further, the core member connected body 10, 2 shown in FIG.
At 0 and 30, the long core material and the short core material are alternately arranged, and as a result, the long core material is arranged on one outer side. For example, a plurality of short core materials and one In the case of using the long core material to form a core material connected body other than those shown in FIGS. 1A to 1C, similarly, one long core material is disposed between the short core materials. Be sure to place the long core material on one outside so that it does not occur. If the long core material is placed on one of the outsides and the upper end of the long core material is erected on the soil surface so that the upper end of the long core material can be seen on the ground surface, the core in the next process can be used. At the time of erection work of the linked material, the upper end of the long core material can be used as a mark, and the interval between the linked material members can be accurately set.

Further, at least two of the short core members 11, 21, 31 and the long core members 12, 22, 32 are respectively provided.
A wire connection hole (not shown) is formed at the upper end of the book core.

Next, a method of assembling the core material connected body will be described with reference to FIG. Prior to the construction, a cement-based injection liquid was injected into the ground from the tip of the mixing device at the location where the soil cement column wall was to be constructed.
The in-situ soil and the infusate are stirred and mixed to form a soil cement wall.

Next, a hoist such as a crane (not shown)
The hanging tool 50 is hung down. The suspending device 50 is suspended by suspending wires 45, 45 suspended from a hoist, etc., suspending hardware 46 secured to the suspending wires 45, 45, and suspended by the suspending hardware 46. And hanging wires 47, 47.

The hanging wire 47 of the hanging tool 50,
The lower end of 47 is connected to a wire connection hole formed at the upper end of the long core material 42, and the core material connected body 40 is lifted by a hoist. Then, if the suspended core material linking body 40 is suspended in the soil cement pre-constructed in the ground,
The core material linking body 40 can be erected. At the time of building, the core material linking body 40 sinks into the soil cement by its own weight, so that it is not necessary to apply external force using a pile driver or the like.

[0019]

According to the present invention, a plurality of core members arranged substantially in parallel at predetermined intervals are connected together in advance by a connecting member to form a core member connected body. Because it was built in the underground wall like a wall,
Even when earth pressure acts on the core material connected body at the time of building, the core materials are mutually held by the connecting member, and it is possible to prevent the core material from being twisted. Therefore, as compared with the underground wall which is formed by laying the core material one by one as in the related art, the accuracy of the core material is significantly improved, and thus, the occurrence of cracks in the underground wall is prevented. Water leakage can also be prevented. Also, in comparison with the conventional method of constructing the core material one by one, the method of constructing the core material connected body and the core material according to the present invention allows a plurality of core materials to be simultaneously constructed. The construction period can be shortened.

Further, according to the present invention, a core material connected body is formed in advance and this core material connected body is erected in an underground wall such as a soil cement column wall, so that the upper end of a part of the core material is A core material to be buried underneath, for example, a core material with a large core spacing near the ground surface where the earth pressure is relatively low, and a narrow core density near the flooring part where the earth pressure is relatively large. Material allocation is also possible. Therefore, the amount of the core material can be reduced, and the material cost can be reduced.

[Brief description of the drawings]

FIGS. 1 (a) to 1 (c) are front views showing a core material connected body of the present invention.

FIG. 2 is a sectional view taken along the line II-II of FIG. 1 (b).

FIG. 3 is a perspective view showing a state in which the linked core material of the present invention is lifted.

FIG. 4 is a conventional design drawing, which is a cross-sectional view of a retaining wall, a layout of core materials, and a design side pressure diagram.

[Explanation of symbols]

10, 20, 30 Core material connection body 11, 21, 31 Short core material (core material) 12, 22, 32 Long core material (core material) 13a, 23a, 33a Back flat bar (connection member) 23b Body side flat Bar (connecting member)

Claims (3)

[Claims] 1. A plurality of core members arranged substantially in parallel at predetermined intervals, and a connecting member for integrally connecting the plurality of core members, whereby the plurality of core members can be simultaneously built in the ground. A linked core material used for an underground wall, characterized in that: 2. A plurality of core members are arranged substantially in parallel at predetermined intervals, and the plurality of core members are integrally connected to form a core member connected body. How to build the core material to be built. 3. A plurality of core materials having two or more kinds of lengths are arranged substantially in parallel at a predetermined interval, and the plurality of core materials are integrally connected to form a core material connected body. A method of building a core material to be built in the ground after lifting the core material, wherein when forming the core material connected body, a short core material of the plurality of core materials is a section where the earth pressure in the ground is large. A method for installing a core material, wherein the core material is disposed so as to be located at a position.