JPH02248788A - Method for burying middle manhole - Google Patents

Abstract

PURPOSE:To carry out a work from drilling using a vertical shaft to placement of water-stop concrete without performing foundation improvement by making a working pipe stand from the pipe wall of a buried pipe including a connection hole to be opened through the buried pipe after drilling using the vertical shaft, and cutting off the inside of the working pipe from that of the vertical shaft located outside thereof. CONSTITUTION:After a vertical shaft 1 is used to drill a hole to the depth of a buried pipe A, a cleaning device 20 is suspended in a casing B by a wire 21 and is rotated so that earth and sand on the inner wall of the casing B and on the surface of the buried pipe A is swept off by a scraper 22. A working pipe 2 is next set in the casing B and compressed air or water is supplied thereto, and the air or water is blowed out from an adsorbing pad 4 and from the surface of the buried pipe A so that the surface of the buried pipe A is purified. Thereafter, a connection pipe 3b is switched to the vacuum pump side and the main body 3 is set to negative pressure, whereby the adsorbing pad 4 is stack to the surface of the buried pipe A. Then water stop concrete D is injected from the lower end of a tremie pipe 6 to below a guide plate 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a construction method for newly installing an intermediate manhole in an existing buried sewer pipe.

[-Conventional technology]

Conventionally, when constructing an intermediate manhole in an underground pipe, a construction method has generally been adopted in which a vertical shaft is excavated to the position of the buried pipe and the manhole is constructed inside the shaft. Excavation of a shaft is
For example, the present applicant filed the application first and filed the patent application under JP-A No. 61-8371.
The method disclosed in Publication No. 9 can be used. this is,
The interior of the steel casing is excavated while being press-fitted. When constructing a manhole in an existing buried pipe, the method is similar to excavating a vertical shaft to the depth of the buried pipe.

The work of constructing an intermediate manhole into a buried pipe starts by excavating a shaft up to the buried pipe according to the above-mentioned excavation procedure and exposing the buried pipe into the shaft. After this, a worker enters the shaft or uses a dedicated cleaning device to remove dirt and the like adhering to the inner wall of the casing. Then, the bottom of the pit will be leveled and water-stop concrete will be placed to prevent groundwater from gushing out and to serve as the foundation for the manhole. During such work, underground water springs up, so it is necessary to improve the ground by injecting a chemical solution around the casing and buried pipe.

Next, a hole is drilled in the buried pipe to connect the manhole frame. In this process, the solidified water-stop concrete is lifted from the top to the outside of the buried pipe, and a hole for the sheath pipe is drilled in the buried pipe. Conventionally, this kind of hole-drilling work has been done manually, by passing a sheath pipe through an insertion hole drilled in waterproof concrete and fixing it with mortar.

The sheath pipe is inserted into the hole in the buried pipe, and the gap between the water-stopping concrete and the sheath pipe is filled with mortar to form an introduction path. Then, as a final step, an intermediate manhole is constructed on top of the internal pipe, and the manhole frame and the buried pipe are connected.

[Problem to be solved by the invention] However, in the past, workers had to enter the shaft to work before placing water-stopping concrete, so it was necessary to stop water around the buried pipes for this work. Yes, the ground must be improved. This ground improvement is one of the reasons why the work is uncertain, the labor costs are high, and the construction period is long. In addition, buried pipes may shift from their original positions, and this movement may have a negative impact on surrounding buildings. Furthermore, chemicals injected into the ground for soil improvement may mix into well water, causing environmental problems.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a construction method that allows work to be carried out from the time of excavating a shaft to the time of placing water-stop concrete without soil improvement.

[Means to solve the problem]

In order to achieve the above object, the intermediate manhole burying method of the present invention is a construction method in which a shaft is excavated toward the buried pipe, and a connecting hole for communicating and connecting to the manhole is opened from the shaft to the buried pipe, After excavating the shaft, a working pipe including a connection hole opened in the buried pipe is raised from the pipe wall of the buried pipe, the inside of the pipe is isolated from the outside of the shaft, and a pressurized fluid is supplied to the inside of the working pipe. Clean the surface by spraying water onto the surface of the buried pipe, fill water-stop concrete around the work pipe, and after the water-stop concrete hardens, make a work hole from the surface to the surface of the buried pipe, and perform the work. A connecting hole is made in the buried pipe using a cutter passed through the hole, a sheath pipe is passed through the working hole and connected to the connecting hole, and mortar is filled between the surrounding area and the working hole, and a manhole is constructed and the lower end of the pipe is closed. is characterized in that it is communicatively connected to the sheath pipe.

〔Example〕

Hereinafter, features of the present invention will be specifically explained with reference to embodiments shown in the drawings.

FIGS. 1(a) to (i) are diagrams showing the steps of the present invention,
This will be explained in order.

In FIG. 1(a), a vertical shaft 1 is formed by a casing B toward a buried pipe A. In FIG. As mentioned in the prior art section, the excavation of this vertical shaft 1 is carried out, for example, in
This is carried out using the apparatus described in Japanese Patent No. 83719. Note that groundwater C has accumulated in the casing B due to the excavation of the shaft 1.

Figure 1 et al.) shows that after excavating shaft 1 to the depth of buried pipe A,
Insert the cleaning device 20 into the casing B with the wire 21
Shows the suspended state. The cleaning device 20 rotates inside the casing B and has a scraper 22 provided at the lower end.
By this, it is possible to shake off the earth and sand adhering to the inner wall of the casing B, and also to shake off the earth and sand deposited on the surface of the buried pipe.

FIG. 1(C) shows a state in which the working pipe 2 is set in the casing B in order to carry out work such as cleaning the surface of the buried pipe A and filling it with waterproof concrete after the cleaning work. The working pipe 2 includes a hollow cylindrical main body 3 as shown in FIG. 2, and a suction pad 4 at the lower end.
has been established. This suction pad 4 is formed into a bell mouth shape so that it can be closely attached along the peripheral wall of the buried pipe.

The main body 3 has an upper main body 31 and a lower main body 32 that can be separated from the flanges 313 and 328, respectively, and is provided with a guide plate 5 that also serves as a weight on the outside. The guide plate 5 is integrated with the upper body 31, and the bolts 5a provided at the lower end are inserted into the holes of the flanges 31a and 32a.
The upper and lower main bodies 31 and 32 are separably integrated with this pole 5a and a nut 33.

Furthermore, a communication hole 3a is provided at the upper end of the main body 3 for use in supplying compressed air and pressure water, and a connection hose 3 connected to the communication hole 3a is provided at the upper end of the main body 3.
It can be hung using b. This connection hose 3b is
It is connected to a compressor, pressure water pump, vacuum pump, etc. on the ground so that it can be switched, and the working pipe 2
The suction force of the suction pad 4 can be increased by supplying compressed air or pressurized water to the suction pad 4, or by creating a negative pressure inside the suction pad 4. Further, the guide plate 5 is provided with a roller 5b that slides along the inner wall of the casing B.

In FIG. 1(C), compressed air or pressurized water is supplied to the working pipe 2, and the surface of the buried pipe A is cleaned by jetting air or water from the suction pad 4 and the surface of the buried pipe A. Thereafter, the connection hose 3b is switched to the Paquine pump side, and the inside of the main body 3 is set to negative pressure. As a result, the suction pad 4 also receives the water pressure of external underground water, and is tightly adhered to the surface of the buried pipe A. In this way, even if the surface of the buried pipe A is rough, the degree of adhesion of the suction pad 4 is maintained high, and the inside and outside of the main body 3 are completely partitioned off.

FIG. 1(d) shows the process of supplying water-stop concrete, in which a tremor pipe 6 is inserted into a casing B. Water-stop concrete D is injected from the lower end of the tremor pipe 6 and placed to such an extent that the area below the guide plate 5 is buried. By placing this waterproof concrete (D), the working vibrator 2, which is integrated with the buried pipe A by the suction pad 4, is held without changing its position.

FIG. 1(e) shows the process of installing a submersible pump 7 in the casing B to pump up and empty the groundwater in the casing B, and then drilling a connection hole to the buried pipe. In this process, after pumping up groundwater, the upper body 3 of the working pipe 2 is
1 along with the guide plate 5 from the lower body 32 and recovered on the ground. This separation is performed by an operator entering the casing B and removing the nut 33 from the bolt 5a. In this work, the water-stop concrete D has solidified, so there is no danger to the workers.

Through the above operations, the upper body 31 and the guide plate 5 are recovered to the ground, and a working hole d is created in the solidified waterproof concrete D with the lower body 32 remaining between the buried pipe and the pipe serving as a sleeve. It turns out. Then, cutter 8 from the ground
Suspend it and pass it through this working hole d, and make a hole in the buried pipe while scraping the pipe wall. As a result, a connection hole a that forms a flow path with the intermediate manhole is opened in the pipe wall of the buried pipe.

After opening the connection hole a, collect the submersible pump 7 and cutter 8, and insert the sheath pipe 9 into the connection hole a as shown in FIG. The work vibrator 2 is inserted into the lower body 32, and the lower end is inserted into the connecting hole a while being guided by the inner wall of the lower body 32.
can be located in After that, connect the lower end of the mortar supply pipe 10 to the lower body 32 and the sheath pipe 9 as shown in
and fill it with mortar E. By filling this mortar E, the sheath pipe 9 becomes a solidified water stop concrete around the bottom of the shaft 1! It is integrated into the j-to-D.

After the above steps, the intermediate manhole ti shown in FIG. At this time, the remaining lower body 3 of the work vibrator 2
2, the lower end of the intermediate manhole 11 fits into the periphery of the connecting structure. Then, as a final step, as shown in FIG. 1(i), if the casing B is filled with mortar F, an underground structure consisting of the buried pipe and the intermediate manhole 11 is constructed. Note that lla indicates a sewer pipe newly connected to the intermediate manhole 11 or connected from another system.

〔Effect of the invention〕

As explained above, in the construction method of the present invention, the steps up to placing waterproof concrete can be performed underwater.

For this reason, there is no need to perform ground improvement to stop water so that workers can enter the casing and perform work as in the past, and various troubles associated with ground improvement are eliminated. Further, since there is no need to work inside an unstable casing, the work can be done safely, and there is no need for wasteful work such as scraping off water-stopping concrete that has already been cast once more in preparation for inserting the sheath pipe.

[Brief explanation of drawings]

FIGS. 1(a) to (i) are diagrams showing the construction method of the present invention in the order of steps, and FIG. 2 is a diagram showing an outline of a sheet pipe. 1: Vertical shaft 2 Nijido pipe 3: Main body
3a: Communication hole 3b: Connection hose 4: Suction pad 5 guide plate 5a: Bolt 5b: Roller 6: Treme pipe 7: Submersible pump 8: Cutter
9: Sheath pipe 10: Mortar supply pipe 11: Intermediate manhole 11a
: Sewer pipe 31: Upper body 32: Lower body 31a, 32a
:Flange 33:Nut A:Buried pipe a:
Connection hole B: Casing D: Water stop cement C: Groundwater d: Working hole E: Mortar Patent applicant Kyoei Tokenyo Co., Ltd. Masu Kobori (and 2 others) 1st year (h)

Claims (1)

[Claims] 1. A construction method in which a shaft is excavated toward the buried pipe, and a connecting hole for communicating with the manhole is opened from the shaft to the buried pipe, and the method includes the connecting hole to be opened in the buried pipe after excavating the shaft. A working pipe is raised from the pipe wall to isolate the inside of the pipe from the outside shaft, supplying pressure fluid to the inside of the working pipe and jetting it onto the surface of the buried pipe to clean the surface, and cleaning the surface of the buried pipe. Fill water stop concrete around the pipe, and after the water stop concrete has solidified, make a working hole from its surface to the surface of the buried pipe, use a cutter passed through the work hole to make a connection hole in the buried pipe, and perform the work. Intermediate manhole embedding characterized in that a sheath pipe is passed through the hole and connected to the connection hole, and mortar is filled between the periphery and the working hole, and further a manhole is constructed and its lower end is communicated and connected to the said sheath pipe. Construction method.