JPH11159287A - Concrete pipe for semi-shield method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a concrete pipe for a semi-shield method eliminating the protrusion of a distribution pipe in a perforated pipe without impeding survey, carry-out of excavated earth, and the like even in the case of a small bore pipe. SOLUTION: A tail void pressure material distribution pipe 32 is embedded within the thickness of a peripheral wall in a perforated pipe 31, along the circumferential direction of the peripheral wall. The outer peripheral surface of the peripheral wall is provided with the required number of pressure material injection holes 33 in the state of being communicated with the distribution pipe 32. The distribution pipe 32 is connected to a tail void pressure material feed pipe 20 on the interior side of the perforated pipe 31. At the time of execution of a semi-shield construction method, tail void pressure material is filled into a tail void 16 from the injection holes 33. The perforated pipe 31 does not have a protrusion on the inner periphery, and survey, carry-out of excavated earth by a pipe, and the like can be performed without hindrance even in the case of a small bore pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete pipe used in a semi-shield method for constructing a pipeline in the ground, and more specifically, a tail void pressurizing material is injected into a tail void which is an overcut portion dug during propulsion. Related to concrete pipes used for

[0002]

2. Description of the Related Art A semi-shield method has been adopted as a method of constructing a pipeline for storing sewerage facilities and various underground objects underground.

As shown in FIG. 3, the semi-shield method is:
A jack 12 and a reaction support plate 13 are installed in the starting shaft 11, and a shield excavator 14 and a concrete propulsion pipe 15, which excavate and operate, are pushed into the ground by the jack 12, and the propulsion pipe 15 is added. , And the shield excavator 14 is taken out to the arrival shaft, thereby constructing a pipeline in the ground.

[0004] In recent years, in the construction of the semi-shield method, in order to reduce the construction cost in consideration of densely populated areas and congested roads and to reduce construction costs, a construction method capable of reducing the number of shafts and capable of long-distance propulsion is strongly demanded. Have been.

In the semi-shield method, the most important issue for long-distance propulsion is to reduce friction between the propulsion pipe and the underground soil.

[0006] The conventional method of reducing friction in the semi-shielding method is that when the propulsion device 14 and the propulsion tube 15 following the propulsion device are propelled into the ground, an extra excavation function is added to the propulsion device 14 so that the propulsion device 15 is provided on the outer periphery of the propulsion tube 15. A tail void 16 which is an overcut portion dug out by about 50 mm is excavated, a perforated pipe 17 is incorporated in the middle of the propulsion pipe 15, and a tail void pressurizing material supply pipe 19 is inserted into a backfill injection hole 18 provided in the perforated pipe 17. And by injecting the tail void pressurizing material A into the tail void 16, the tail void 16 is secured, and the tail void pressurizing material A reduces the frictional resistance between the propulsion pipe 15 and the underground soil during propulsion. I have to.

As shown in FIG. 4, a specific supply of the tail void pressurizing material A is provided by disposing a tail void pressurizing material distribution pipe 19 in an annular shape along the inner circumference inside a concrete perforated pipe 17 as shown in FIG. The distribution pipe 19 and each backfill injection hole 1
8, the supply pipe 20 is connected to the distribution pipe 19, and the tail void pressurizing material A is supplied from the ground, so that the tail void pressurizing material A is injected into the tail void 16.

[0008]

The propulsion pipe 15
And when the perforated pipe 17 is a large diameter pipe having a diameter of 800 mm or more,
Even if the distribution pipe 19 is arranged on the inner periphery of the perforated pipe 17, there is no obstacle to human traffic, and operations such as surveying and excavating soil can be carried out without any problem.

On the other hand, if the propulsion pipe 15 and the perforated pipe 17 are small-diameter pipes having a diameter of 700 mm or less, no human traffic is possible, but work such as surveying and carrying out excavated soil using pipes is necessary. In addition, if the distribution pipe 19 is arranged on the inner periphery of the perforated pipe 17, there is a problem that the above-mentioned operation is hindered.

Accordingly, an object of the present invention is to provide a concrete pipe for a semi-shielded construction method which eliminates the protrusion of a distribution pipe in a perforated pipe and does not hinder the work of surveying and carrying out excavated soil even in the case of a small diameter pipe. To provide.

[0011]

In order to solve the above-mentioned problems, the invention of claim 1 is to provide a distribution pipe of a tail void pressurizing material within a thickness of a peripheral wall of a concrete pipe along a circumferential direction of the peripheral wall. A necessary number of pressurizing material injection holes are buried and provided on the outer peripheral surface of the peripheral wall in a state of communicating with the distribution pipe, and the distribution pipe is connected to the supply pipe of the tail void pressurizing material on the inner side of the concrete pipe. The configuration is adopted.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG.
And FIG. Note that the same parts as those in the related art are denoted by the same reference numerals and description thereof will be omitted.

As shown in the drawing, the concrete pipe of the present invention is a pipe arranged in a connected state between propulsion pipes in the semi-shielding method, and is hereinafter referred to as a perforated pipe.

A distribution pipe 32 for the tail void pressurizing material is buried along the circumferential direction of the peripheral wall within the thickness of the peripheral wall of the perforated pipe 31, and a required number of pressurizing material injection holes 33 are formed on the outer peripheral surface of the peripheral wall. The distribution pipe 3 is provided in communication with the pipe 32.
2 is connected to the supply pipe 20 of the tail void pressurizing material on the inner side of the perforated pipe 31.

The distribution pipe 32 is formed in an annular shape to fit within the thickness of the peripheral wall of the perforated pipe 31. When the perforated pipe 31 is formed by rotary centrifugal force, the distribution pipe 32 is previously incorporated into its mold and the distribution pipe 3 is formed.
2, a short pipe which is a connection part 34 with the pressurized material injection hole 33 and the supply pipe 20 is provided in a communicating manner, and the distribution pipe 32 is buried at the same time when the porous pipe 31 is formed by concrete.
At the same time, a pressure material injection hole 33 is formed. The number and interval of the pressurizing material injection holes 33 may be set so that the tail void pressurizing material A can be uniformly injected over the entire periphery of the tail void 16.

Here, the tail void pressurizing material A is mainly composed of sodium polyacrylate, and water is added thereto to adjust the pH.
7 (neutral), transparent, spherical and viscous, exhibiting the effect of clogging between soil particles, and have the function of instantaneously forming a mud film (mud film) to maintain fluid pressure.

The supply pipe 20 for the tail void pressurizing material A is arranged along the axial direction on the inner periphery of the perforated pipe 31, and the distribution pipe 3
2 is connected to the distribution pipe 3 for the supply pipe 20.
An electromagnetic valve 35 for performing communication and shut-off of the second communication is provided.

Further, the tail void 16 is provided in the porous tube 31.
A pressure detection hole 36 of the tail void pressurized material A injected into the hole is provided so as to penetrate inside and outside, and a control box 37 is connected to an inner end of the pressure detection hole 36 via a pressure sensor 38,
The opening and closing of the solenoid valve 35 is controlled by detecting the pressure of the tail void pressurizing material A by the control box 37. This ensures that the tail void 16 is secured over the entire circumference.

As shown in FIG. 1, the perforated pipes 31 having the above-described structure are incorporated at appropriate intervals between the propulsion pipes 15 which are sequentially connected and pushed in during the construction of the semi-shield method, The supply pipe 20 is connected to a press-fitting device on the ground, and when entering the ground, the tail void pressurizing material A is supplied from the press-fitting device, and the tail void 16 is supplied from the pressurizing material injection hole 33 through the supply pipe 20 and the distribution pipe 32. , A tail void pressurizing material A is injected to reduce the frictional resistance between the propulsion pipe 15 and the perforated pipe 31 and the ground.

Since the distribution pipe 32 is buried within the thickness of the peripheral wall of the perforated pipe 31, the distribution pipe 32 does not protrude into the inside and there are no obstacles in the pipe. In this case, surveying and excavated soil removal can be performed without any trouble.

[0021]

As described above, according to the present invention, since the distribution pipe for the tail void pressurizing material is buried within the thickness of the peripheral wall of the concrete pipe used in the semi-shield method, the distribution pipe is projected on the inner periphery of the concrete pipe. Since there is no occurrence and there are no obstacles in the pipe, especially in small diameter pipes of 700 mm or less,
Surveying and unloading of excavated soil by pipes can be performed without any trouble.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a construction state of a semi-shield method using a concrete pipe of the present invention.

FIG. 2 is a longitudinal sectional view of a concrete pipe.

FIG. 3 is a cross-sectional view showing a construction state of a conventional semi-shield method using a concrete pipe.

FIG. 4 is a longitudinal sectional view of the concrete pipe of the above.

[Explanation of symbols]

 31 perforated pipe 32 minute pipe 33 pressurized material injection hole 34 connection part 35 solenoid valve 36 detection hole 37 control box

Claims (1)

[Claims] 1. A distribution pipe for a tail void pressurizing material is buried along the circumferential direction of the peripheral wall within the thickness of the peripheral wall of the concrete pipe, and a required number of pressurizing material injection holes are formed on the outer peripheral surface of the peripheral wall. A concrete pipe for a semi-shield method in which the distribution pipe is provided in communication with the supply pipe for a tail void pressurizing material inside the concrete pipe.