JPH06248650A - Landslide protection method - Google Patents

Abstract

PURPOSE:To construct easily an underground structure for constituting an underground building frame with fewer or no timberings. CONSTITUTION:Outer peripheral landslide protection walls 1 for outer peripheral excavation in an exterior position, inner peripheral landslide protection walls 2 positioned inside the outer peripheral landslide protection walls 1 and horizontal RC beams 3 extending from leg parts 1a of the outer peripheral landslide protection walls 1 to heads 2a of the inner peripheral landslide protection walls 2 are provided. The leg parts 1a of the outer peripheral landslide protection walls 1 are held firm with the horizontal RC beams 3, and movement of the leg parts 1a caused by earth and water pressure is transferred to the horizontal RC beams 3 on both ends and is restrained therewith while movement of the heads 2a of the inner peripheral landslide protection walls 2 is restrained. Therefore, horizontal force can be transferred to both ends of the horizontal RC beams 3. Furthermore, a self-sustaining landslide protection structure can be built, with the horizontal RC beams 3 serving as head joints, in the case where excavation is made to a depth deeper than a bottoming depth on the outer peripheral part. Therefore, the size of members for timbering can be made smaller, while span for installation of the timberings can be lengthened, making the construction satisfactory with requirement for the timberings reduced to small numbers or nothing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mountain retaining method for constructing an underground skeleton such as an underground slab by constructing an earth retaining structure around the underground construction portion to carry out the construction work of the underground skeleton. .

[0002]

2. Description of the Related Art Conventionally, as a pile retaining method of this kind, a pile retaining wall such as a sheet pile and a soil mixing wall is built around the periphery in advance, and then root cutting is carried out while supporting a support for the pile retaining wall. It is generally known to construct waste concrete, underground slabs, etc. one after another.

[0003]

[Problems to be Solved by the Invention] However, in the above-mentioned conventional mountain retaining method, the supporting work for supporting the surrounding mountain retaining wall is carried out when constructing an underground skeleton such as discarded concrete or an underground slab. It is an obstacle to the above.

Therefore, if the conventional mountain retaining method as described above is adopted, the construction work of the underground skeleton itself is troublesome and requires a lot of time due to the support work.

The present invention was devised in view of the above-mentioned circumstances, and an object thereof is to reduce or eliminate support work, and to easily perform an operation of forming an underground construction part for constructing an underground skeleton. It is to provide a mountain retaining method that can be done.

[0006]

According to the earth retaining method of the present invention (see FIG. 1), first, an outer peripheral mountain retaining wall 1 for outer peripheral excavation at an outer position and an inner peripheral mountain retaining wall at an inner position of the outer peripheral mountain retaining wall 1. Build the wall 2. At the time of this construction, the outer peripheral mountain retaining wall 1 is set to a depth such that it can be self-supported, and the inner inner peripheral mountain retaining wall 2 is set to be deeper than the floor attachment depth of the outer peripheral portion.

Next, excavation is performed to the depth of the outer peripheral floor, and the legs 1a of the outer peripheral mountain retaining wall 1 to the head of the inner peripheral mountain retaining wall 2 are excavated.
Place concrete of the required thickness between 2a and level R
The C-beam 3 is provided. When the horizontal RC beam 3 is provided, if necessary, the unbonded PC steel wire 4 may be placed in the concrete and the unbonded PC steel wire 4 may be tensioned after the concrete is hardened.

The outer peripheral mountain retaining wall 1 and the inner peripheral mountain retaining wall 2
Introducing a horizontal RC beam 3 placed between and the unbonded PC steel wire 4 to this, the leg portion 1a of the peripheral mountain retaining wall 1 is restrained by this tension force, and the leg portion 1a is moved by soil water pressure. To the horizontal RC beams 3 at both ends to suppress the movement of the head 2a of the inner peripheral mountain retaining wall 2.

From the above, according to the mountain retaining method of the present invention, the horizontal RC beam can be arranged at the leg portion of the outer peripheral mountain retaining wall and the horizontal force can be transmitted to both ends of the beam. Further, for excavation at a depth deeper than the flooring depth of the outer peripheral portion, this horizontal RC beam can be used as a head tie to form a self-supporting mountain retaining frame.

Therefore, according to the clasping method of the present invention, it is possible to reduce the member size of the supporting work, lengthen the span of the supporting work, reduce the supporting work, or eliminate the supporting work. It can be made advantageous in construction.

[0011]

Embodiments of the present invention will be described below with reference to the illustrated embodiments.

[0012] In the earth retaining method of the present invention, that is, when constructing an underground skeleton (not shown) such as abandoned concrete or an underground slab, earth retaining around the underground construction portion prevents landslides from occurring. The earth retaining method for carrying out the construction work of the skeleton (see Fig. 1) is as follows. First, for excavation up to a depth where the mountain retaining wall can stand on its own, the outer peripheral retaining wall 1 and the outer periphery The inner peripheral mountain retaining wall 2 is provided for excavation of a portion deeper than the flooring depth of each part.

Further, a horizontal RC beam 3 formed by casting concrete with a required thickness is laid between the leg portion 1a of the outer peripheral mountain retaining wall 1 and the head 2a of the inner peripheral mountain retaining wall 2.

Then, the horizontal RC beam 3 restrains the leg portion 1a of the outer peripheral mountain retaining wall 1 and the head portion 2a of the inner peripheral mountain retaining wall 2 to pass the horizontal force due to the earth pressure to both ends of the horizontal RC beam 3. The movement of the legs 1a and the head 2a on the outer and inner mountain retaining walls 1 and 2 is suppressed.

The horizontal RC beam 3 as a material for raising the belly
Receives a large compressive force at its outer center and a large tensile force at its corners. For this reason, a planar beam member causes buckling and splashing.

The buckling and the recoil of the horizontal RC beam 3 are provided on the outer side of the horizontal RC beam 3.
That is, it is prevented by the outer peripheral mountain retaining wall 1 provided for excavation up to a depth such that it can stand on its own.

The above-described mountain retaining method of the present invention will be described in detail with reference to the drawings along with the steps of actually performing it. First, as shown in FIG. 2, an outer peripheral mountain retaining wall 1 and an inner peripheral mountain retaining wall 2 (outer periphery). (Parts deeper than the floor) are installed at specified positions.
Then, as shown in FIG. 3, excavation is performed to the outer peripheral flooring level.

Next, as shown in FIG. 4, the outer peripheral mountain retaining wall 1
The reinforcement 1a and the head 2a of the inner peripheral mountain retaining wall 2 are laid out (the amount of reinforcing bar is determined by calculation), and unbonded PC steel wire 4 is laid if necessary and concrete is poured. Then, after the strength of the concrete is developed, tension is introduced into the unbonded PC steel wire 4.

Next, as shown in FIGS. 5 and 6, the portion surrounded by the inner peripheral mountain retaining wall 2 is excavated to a predetermined floor-attached surface. At this time, supporting works 5 are installed if necessary. Then, by such an outer peripheral mountain retaining wall 1, an inner peripheral mountain retaining wall 2 and a horizontal RC beam 3, a ground skeleton is constructed in a portion excavated by preventing a landslide.

[0020]

According to the present invention, the outer peripheral mountain retaining wall and the inner peripheral mountain retaining wall, and the horizontal RC beam provided between the leg of the outer peripheral mountain retaining wall and the head of the inner peripheral mountain retaining wall are provided. It is possible to reduce or eliminate the support work such as uprising, cuttings, diagonal members, and columns. Therefore, it is possible to improve the efficiency of the work of excavating the underground construction part and constructing the underground structure.

[Brief description of drawings]

FIG. 1 (a) is a schematic view showing an underground construction part excavated by adopting the mountain retaining method of the present invention, and FIG. 1 (b) is a view taken along the line AA of (a).

FIG. 2 is a partial schematic process drawing showing an excavation state of an underground construction part, which is carried out by adopting the mountain retaining method of the present invention.

FIG. 3 is a partial schematic process drawing showing an excavated state of an underground construction part, which is carried out by adopting the mountain retaining method of the present invention.

FIG. 4 is a partial schematic process drawing showing an excavation state of an underground construction part, which is carried out by adopting the mountain retaining method of the present invention.

FIG. 5 is a partial schematic process drawing showing an excavation state of an underground construction part, which is carried out by adopting the mountain retaining method of the present invention.

FIG. 6 is a partial schematic perspective view showing an underground construction part excavated by adopting the mountain retaining method of the present invention.

[Explanation of symbols]

1 ... Outer peripheral retaining wall, 1a ... Legs, 2 ... Inner peripheral retaining wall, 2a ...
Head, 3 ... Horizontal RC beam, 4 ... Unbonded PC steel wire, 5 ...
Support work.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kakuyuki Takatsu 2-19-1 Tobita-Su, Chofu-shi, Tokyo Kashima Construction Co., Ltd. Technical Research Institute

Claims (1)

[Claims] 1. When constructing an underground skeleton such as abandoned concrete or an underground slab, a mountain retaining is provided around the underground constructing part to prevent a landslide, and a mountain retaining for carrying out the construction work of the underground skeleton. It is a construction method, and for excavation up to the depth where the mountain retaining wall can stand on its own, an outer peripheral retaining wall is provided on the outer peripheral part of the underground construction part, and an inner peripheral retaining wall is used for excavating a part deeper than the flooring depth of the outer peripheral part. While each wall is provided, a horizontal RC beam formed by placing concrete with a required thickness is laid between the leg portion of the outer peripheral retaining wall and the head of the inner peripheral retaining wall. The leg of the retaining wall and the head of the inner retaining wall are restrained so that the horizontal force due to earth pressure can be passed to both ends of the horizontal RC beam, and the foot of the retaining wall inside and outside Retaining construction method which comprises suppressing the movement of the head and.