JPH06294287A - Structure of vertical shaft wall which shield has reached - Google Patents

Abstract

PURPOSE:To make easy and quick removal of a portion through which a shield is to pass. CONSTITUTION:In a vertical shaft which is surrounded by a side wall 2 and reached by a shield, a portion of the vertical shaft side wall 2 through which a shield machine 3 is to pass is cut at its edge to form a block wall 4. The inside of the block wall 4 and the natural-ground side of the vertical shaft side wall 2 are connected together by means of a bar-shaped fastening member 6 and the block wall 4 is freely removable by removal of the fastening member 6.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a structure of a shield reaching shaft wall.

[0002]

2. Description of the Related Art As a method of removing a reaching shaft wall through which a shield machine penetrates, a method is generally adopted in which a planned penetration portion of the reaching shaft wall is removed by a breaker or the like.

[0003]

Problems to be Solved by the Invention There are the following problems in the above-mentioned conventional technique for removing the through portion.

<I> A lot of time and labor is required for the hanging work and the cutting of the reinforcing bar in the wall.

<B> Since work is performed in the deep underground, work efficiency is poor.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to remove a shield penetration portion easily and in a short time.
It is to provide the structure of the shield reaching shaft.

[0007]

[Means for Solving the Problems] That is, the present invention is a shield reaching shaft surrounded by a wall, in which a shaft wall at a planned penetration site of a shield machine is cut to form a block wall, The shield reaching vertical shaft wall structure is configured such that the inside of the block wall and the ground side of the vertical shaft wall are connected by a rod-shaped fastening member, and the block wall is detachable by removing the fastening member.

[0008]

Embodiment 1 An embodiment of the present invention will be described below with reference to the drawings.

<B> Overall Configuration FIG. 1 is a vertical sectional view of the reaching shaft 1. The reaching shaft 1 is a reinforced concrete box surrounded by side walls 2 on all sides, and an opening 5 is provided in the side wall 2 of the shield machine 3 which is to be penetrated, and the opening 5 is blocked by a block wall 4. For the reaching shaft 1 with the block wall 4, the optimum method is selected from the known construction methods (underground wall construction method, caisson construction method, reverse winding concrete construction method, etc.) in consideration of the vertical shaft depth and diameter. .

<B> Block Wall The block wall 4 is a wall made of reinforced concrete, and its cross-sectional shape is a trapezoid in which the side of the reaching shaft 1 is larger than the ground side in consideration of removal to the side of the reaching shaft 1. The minimum diameter of the block wall 4 on the natural side is set to a dimension that allows the shield machine 3 to pass through.

<C> Block Wall Connecting Means The block wall 4 inserted into the opening 5 of the side wall 2 penetrates through the block wall 4 and is screwed to the nut member 7 embedded in the side wall 2. 6 is detachably connected. The connecting bolt 6 is insulated from the block wall 4, and the bolt head is exposed on the surface of the block wall 4 so that the connecting bolt 6 can be rotated from the inside of the reaching shaft 1. In the present embodiment, the case where the connecting bolt 6 is arranged so as to spread toward the shield machine side will be described, but it may be arranged horizontally. Further, the connecting bolts 6 can be arranged in a plurality of stages / rows. If a sheet-like material is interposed between the block wall 4 and the peripheral surface of the opening 5, groundwater can be prevented from leaking from the ground into the reaching shaft 1, and the block wall 4 can be removed when the block wall 4 is removed.
It will be easier to remove.

[0012]

Next, the operation of the reaching shaft 1 will be described.

<A> Construction of the reaching shaft 1 For example, the reaching shaft 1 with the block wall 4 is constructed by the caisson method and is sunk to a predetermined depth. Earth pressure acting on the block wall 4 is supported by a plurality of connecting bolts 6. Here, considering the stress generated on the side wall 2,
Tensile force acts on the inside of, and compressive force acts on the natural side. By connecting the inner surface of the block wall 4 where the tensile force is generated and the side of the side wall 2 where the compressive force is generated with the connecting bolt 6, the connecting bolt 6 functions as a shear strength reinforcing bar of the side wall 2. Therefore, the amount of rebar of the wall itself can be reduced.

<B> Penetration When the shield machine 3 approaches the reaching shaft 1, all the connecting bolts 6 shown in FIG. 1 are removed. Then, as shown in FIG. 2, the block wall 4 is extracted into the inside of the reaching shaft 1. The side wall 2 may be extracted by utilizing the starting force of the shield machine 3 or by using a known device from inside the shaft 1. As a result, the shield machine 3 reaches the inside of the reaching shaft 1 through the opening 5 of the side wall 2.

[0015]

Embodiment 2 FIGS. 3 to 5 show another embodiment in which the tip of the connecting bolt 6 is connected to the structural reinforcing bar 8 of the side wall 2. In FIG. 3, the connecting bolt 6 is composed of a reinforcing bar having a threaded end, a PC steel rod, etc., and is covered with a steel or resin sheath 9 over almost the entire length of the bolt for the purpose of friction cutting inside. It is unbonded by enclosing a lubricant such as grease. Further, as the sheath 9, a heat-shrinkable sheath or a corrugated sheath that adheres to the connecting bolt 6 is used,
When the connecting bolt 6 is positively adhered to the concrete through the sheath 9, the connecting bolt 6 has a function as a reinforcing member as well as a structural reinforcing bar, and a shear reinforcing member (stirrup bar).
Can be expected to function. 3 and 4 show the connecting structure of the tip of the connecting bolt 6. The connecting bolt 6 is integrated with the structural rebar 8 of the side wall 2 via a connecting jig 12 and nuts 13 and 13 that are split in two as shown. Are linked to. Such connecting bolts 6 are assembled together when the structural rebar 8 of the side wall 2 is assembled. Then, as shown in FIG. 1, the block wall 4 is removed after the head portion of the connecting bolt 6 exposed on the inner side of the side wall 2 is rotationally operated and pulled out, as in the first embodiment.

[0016]

Since the present invention is as described above,
Since the wall surface of the part to be penetrated of the shield machine can be easily removed in a short time, the conventional chipping work is unnecessary.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a side wall of a reaching shaft when a block wall is attached.

FIG. 2 is a vertical cross-sectional view of the side wall of the reaching shaft when the block wall is removed.

FIG. 3 is an explanatory view of a second embodiment in which a connecting bolt is connected to a structural rebar of a side wall.

FIG. 4 is an enlarged view of the tip of the connecting bolt.

5 is a sectional view taken along line V-V in FIG.

Claims (1)

[Claims] 1. A shield reaching shaft surrounded by a wall, wherein a shaft wall at a planned penetration site of a shield machine is cut off to form a block wall, and the inside of the block wall and the ground of the shaft wall. The shield side is connected to the mountain side by a rod-shaped fastening member, and the block wall is configured to be removable by removing the fastening member.