JPS6294688A - Method of constructing large-depth shaft - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for constructing deep vertical structures for construction of waterworks, sewers, tunnels, etc.

(Conventional technology) Conventionally, when constructing this type of combing, mountain retaining shoring, caisson etc. were used, and when the groundwater level was high, chemical injection method and deep well method were used as auxiliary methods.

(Problems to be Solved by the Invention) The conventional method has problems in that, although it is affected by the quality of the ground, it requires large-scale construction, increases construction costs, and prolongs the construction period.

(Means for Solving the Problems) The present invention was proposed to solve these problems, and involves setting a large-diameter excavator at the site where the shaft is planned to be constructed,
A shaft is excavated to a predetermined depth using the same excavator, and then a large-diameter steel pipe with a diameter slightly smaller than the diameter of the shaft is built into the shaft while being connected vertically, and the bottom concrete is poured. This method relates to a method for constructing a deep shaft, which is characterized by injecting grout between the diameter steel pipe and the inner wall surface of the shaft and removing water within the copper pipe.

(Function) In the present invention, as described above, a large-diameter excavator is set at the planned construction site to excavate a large-diameter pit to a predetermined depth, and a hole slightly larger than the drilling diameter is placed inside the large-diameter pit. By erecting small-diameter large-diameter steel pipes while joining them in the shaft excavation direction, the large-diameter steel pipes can be easily inserted to a predetermined depth.

After inserting the large-diameter steel pipe to a predetermined depth, concrete is placed at the bottom to fix the bottom of the steel pipe to the inner bottom of the shaft, and grout is injected between the inner wall of the hole and the large-diameter steel pipe. is fixed to the inner wall surface of the shaft, water in the steel pipe is removed, and a shaft is constructed in which the inner wall surface is protected by a large-diameter steel pipe.

(Effects of the Invention) In the present invention, as described above, a large-diameter excavator is used to excavate a pit in a predetermined ground, a large-diameter steel pipe is installed as a wall protection work for the adjacent hole, and the bottom is concreted. Thereafter, grout is injected between the steel pipe and the inner wall surface of the shaft, and the inside of the steel pipe is drained to form a shaft in which a large-diameter steel pipe is integrated within the shaft. For example, a large-diameter excavator can be used to easily construct a deep shaft, which can shorten the construction period and reduce construction costs.

(Example) The present invention will be described below with reference to the illustrated embodiments.

First, a stand pipe (1) is press-fitted into the specified ground, and a large-diameter excavator (3) is inserted into the pipe (1) via a crane (2).
) is suspended and the shaft (A) is excavated by the same excavator (3), and still water (4) or muddy water is injected into the associated hole (diagonal) to prevent the inner wall of the shaft from collapsing.

In the figure, (5) is a suction pump, (6) is a sedimentation tank, and (7
) is a water tank for supplying water to the pit (A), and (8) is a return pipe. (See Figure 1) In this way, the excavator (3) excavates the shaft (
After drilling hole A), use crane (2) to excavate the alliance hole (
A vertical hole (a first steel pipe (Bl) with a diameter slightly smaller than that of the Al) is formed in the Al.
The first steel pipe (B2) is then erected, and both steel pipes (Bl) (B2) are welded on site. The annular buckling prevention material (9) on the inner peripheral surface of the steel pipe is welded at the factory and delivered to the site. (See Figure 2) Similarly, the steel pipe (B1) (
B2) (B3) - (Bn) are joined to form the vertical hole (
A large-diameter steel pipe (B) is erected in the aluminum, the bottom concrete reinforcement material (lot) is suspended, and a tremie pipe αυ is set.

(Fig. 3) Next, the bottom concrete α is poured from the tremie pipe (11).
The bottom of the steel pipe (B) is fixed to the bottom of the shaft (N) (see Figure 4). Next, a grout injection pipe is installed between the steel pipe CB) and the inner surface of the shaft (A). (13), and remove the water in the steel pipe (B3) to construct a shaft in which the inner wall surface of the shaft (A) is protected by the steel pipe (Bl). (See Figure 5) ) According to the embodiment, a large-diameter excavator (3) is used to excavate a vertical hole (Al) at a predetermined depth in a predetermined ground, and a large-diameter steel pipe (B) is integrated into the associated hole fAl. By doing so, it is possible to easily construct a shaft of great depth and large diameter, and the construction period can be shortened and construction costs can be reduced.

Figures 8 to 11 show another embodiment of the present invention, in which, after constructing a shaft by the method described above, an improved ground is created by injecting a chemical into the ground around the outer circumference of the joint of the same leveled comb to the main pile. After that, the main pile (C) is dug to the leveled area. (See Figure 8) Next, cut the pipe wall of the steel pipe (Bl) of the main pile connection part in the shaft, extend the pipe tte in the main pile (C) into the shaft,
(Refer to Figure 9) Reinforcement bars of the upright pipe (Iη) in the leveling shaft connected to the pipe α in the main pile (C) are placed in the same shaft and concrete members are placed. (Refer to the figure) Below, repeat the welding of the pipe αη and the concrete IJ-) (Repeat the Li pouring, and construct a manhole (21%) at the top of the comb to complete the construction of the shaft containing the water pipe. It is something.

Although the present invention has been described above with reference to embodiments, the present invention is of course not limited to these embodiments, and can be modified in various ways without departing from the spirit of the present invention. .

[Brief explanation of drawings]

1 to 5 are longitudinal cross-sectional views showing the steps of an embodiment of the deep shaft construction method according to the present invention, FIG. 6 is a plan view of the bottom concrete reinforcement, and FIG. 7 is the same as that of FIG. The cross-sectional plan view and FIGS. 8 to 11 are longitudinal cross-sectional views showing steps of other embodiments of the present invention. (A)...Mold hole (B)...Steel pipe (3
)...Large-diameter excavator α...Bottom concrete side...Grout agent Patent attorney Shige Okamoto 2 people Fig. 7 Fig. 11

Claims (1)

[Claims] A large-diameter excavator is set at the location where the shaft is planned to be constructed, and the excavator excavates the shaft to a predetermined depth. Next, a large-diameter steel pipe with a diameter slightly smaller than the diameter of the shaft is vertically connected inside the shaft. A method for constructing a deep shaft, which is characterized in that after the shaft is erected, concrete is poured at the bottom, and then grout is injected between the large-diameter steel pipe and the inner wall surface of the shaft, and water in the steel pipe is removed.