JPS6225697A - Method of exchanging underground buried piping - 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 replacing underground pipes.

[Conventional technology]

Cast iron pipes, steel pipes, lead pipes, and asbestos cement pipes buried underground for water, sewer, gas, etc.

Huyum pipes and the like become obsolete beyond their useful life and need to be replaced.

Conventionally, when replacing this buried pipe, the road was dug up along the entire length of the pipe, the old pipe was removed, new pipe was installed in its place, and the road was restored to its original condition.

In addition, the so-called pipe-in-pipe construction method is sometimes adopted as a trenchless construction method. This construction method involves inserting a new pipe with an outer diameter slightly smaller than the inner diameter of the old pipe into the existing old pipe, using this as the new pipe, and leaving the old pipe as a landfill.

[Problem that the invention seeks to solve]

The method of excavating the road along the entire pipeline and replacing the buried pipe is extremely inconvenient as it obstructs the flow of people and vehicles on busy roads, and also requires a lot of civil engineering work, including road restoration work. There are many problems in terms of period, cost, etc.

On the other hand, according to the pipe-in-pipe construction method, the above-mentioned problems can be solved to some extent, but since the diameter of the new pipe is smaller than that of the old pipe, the capacity for water supply, gas supply, etc. is reduced. It has the fatal drawback of going against the current needs, which are increasing in demand. Furthermore, it is not at all preferable to dispose of old pipes in a landfill from the viewpoint of resource reuse.

This invention solves the above-mentioned problems all at once, and is a construction method for replacing underground pipes without digging up the roadbed too much.This invention not only does not reduce the capacity of water supply, gas supply, etc., but may even increase it. This was done in an attempt to provide a new method for replacing underground piping, which not only allows for the reuse of old pipes that are no longer needed.

[Means for solving problems]

A method for replacing underground pipes according to the present invention includes a step of excavating the ground at both ends of a construction area in which pipes are buried to form a forced-in abandoned shaft and a withdrawn abandoned shaft, and a forced-in abandoned shaft formed by the excavation process. The process of installing a pushing machine in an abandoned mine and a pulling machine in a withdrawn mineshaft.A steel for drawing with many locking protrusions formed on its surface is installed in the pipe of the old piping whose both ends are exposed inside each abandoned mine due to the above excavation process. The process of inserting the rod, the process of pouring high-strength mortar in a fluid state between the inner wall of the old pipe and the inserted steel rod, filling it and solidifying it, and
After the mortar has solidified, the tip of the steel rod is gripped by a puller and the old pipe is pulled out into the pull-out shaft, and at the same time the new pipe is pushed into the pull-out shaft by a pusher. There is.

[For production]

The present invention has the above configuration, and in the underground pipe replacement method according to the present invention, by filling and solidifying high-strength mortar inside the old pipe into which the steel rod has been inserted, The old piping and steel rods are joined together with high-strength mortar. Moreover, the connection is strong because the old pipe is joined to the mortar on the entire inner wall thereof, and the steel rod has many locking protrusions formed on its surface. Therefore, when the tip of the steel rod is gripped and pulled by a pulling machine, the old pipe is pulled out from the ground into the extraction shaft together with the steel rod. At the same time, by pushing the new pipe into the soil from inside the pushing shaft using a pushing machine, the new pipe can be easily buried in the burial site of the old pipe. Furthermore, even if the diameter of the new pipe is somewhat larger than the diameter of the old pipe, the new pipe can be buried relatively easily by gradually advancing the new pipe while breaking the earthen wall.

〔Example〕

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

Figures 1-1 to 1-3 are schematic sectional views showing one embodiment of the present invention and for explaining a method for replacing underground piping by dividing it into each stage of work progress. .

First, in Figure 1-1, the old pipe 5 to be replaced
The ground where is buried is excavated at two places to form a push-in abandoned shaft 1 and an extraction shaft 2, and both ends of the old pipe 5 are exposed on the earthen wall surface of each abandoned shaft 1, 2. And the abandoned mineshaft 1
A pushing machine 3 is installed inside, and the new pipe 9 is suspended at a predetermined position, and one end of the new pipe 9 is brought into contact with one end of the old pipe 5 and the other end is brought into contact with the pushing head of the pushing machine 3. On the other hand, a drawing machine 4 is installed inside the drawing abandoned shaft 2. In addition, if the earth wall surface of the pushing abandoned shaft 1 and the pulling abandoned shaft 2 is soft and there is a problem in rear support of the pushing machine 3 and pulling machine 4, back concrete 15 is used to obtain the reaction force for promoting the new pipe and pulling out the eye pipe. and 16, or a plate material is interposed between it and the earth wall surface.

Next, in FIG. 1-2, a steel rod 7 with many locking protrusions 6 formed on its surface is inserted into the old pipe 5, and a fluid state is created between the inner wall of the old pipe 5 and the inserted steel rod 7. High-strength mortar 8 is filled through mortar supply pipe 13 and solidified. Then, compressed air is sent from an external compressed air source to the annular cylinder 11 of the gripping part of the drawing machine 4 through the air supply pipe 14, and the annular cylinder 11 held in the outer cylinder 10 is inflated, thereby removing the gripping plate 12. Push it in the axial direction and securely grip the tip 7A of the steel rod 7.

Subsequently, in the 1st to 3rd times, the drawing machine 4 is operated and f
Pull the R-piece 7 in the direction of arrow a. At this time, since the steel rod 7 has a locking protrusion 6 formed on its surface, the steel rod 7 is engaged with the high-strength mortar 8 closely attached to its outer periphery with strong force, and the old pipe 5 is Because the entire inner wall is bonded with high-strength mortar 8! 11iFs7, high-strength mortar 8, and old piping 5 will be pulled out of the soil as one. Note that the high-strength mortar 8 also serves to prevent damage to the old pipe 5. A portion of the old pipe 5 that has been pulled out into the extraction shaft 2 to almost the full length of the pile is sequentially cut and transported and discharged outside the mine. At the same time, the pushing machine 3 is activated, and the new pipe 9 is gradually advanced in the direction of the arrow by the same distance as the old pipe 5 was moved in the direction of the arrow a. By repeating the above steps, all old piping and new piping within one construction area will be replaced. The above-described operation of the pulling machine 4 and the pushing machine 3 is carried out by the hydraulic jacks 17 and 18 using a hydraulic mechanism, but the oil supply pipe 20A branches from the common hydraulic pressure @19 midway.
, 20B are respectively connected to the pulling machine 4 and the pushing machine 3, and hydraulic pressure is applied to each of the hydraulic jacks 17 and 18 at the same time, so that the forward and backward movements of pulling out the old pipe and pushing in the new pipe are performed in synchronization. .

Although this invention is not particularly limited by the pipe diameter,
If both the old pipe and the new pipe have a diameter of 50 to 300 tm, and the diameter ratio of the old pipe to the new pipe is up to about 1.2 times at the flange part, it can be directly pressed, although it depends on the soil quality. If the number exceeds these, for example, a slice cutter or the like may be attached to the joint head 21 of the new pipe to move it forward while breaking the earthen wall. Also, if the diameter of the new pipe is larger than the diameter of the old pipe, dirt will spill into the new pipe from the gap in the connection, so it is necessary to remove the excess sand to the rear of the new pipe. As in the pushing machine 3 shown in Fig. 2, a screw conveyor 22 is attached to the mechanism, and while rotating the screw conveyor 22, it is gradually advanced by a hydraulic jack 23 in accordance with the movement of the new pipe 9 being pushed. If so, most of the earth and sand will be automatically transported into the pushing shaft 1.

Although the present invention has the configuration described above, the scope of the present invention is not limited by the above-described embodiments and drawings. Any type of puller may be used, and the gripping portion of the drawing machine may be mechanical rather than pneumatic. Further, the shape of the locking protrusion formed on the surface of the steel rod may be any shape as long as it ensures reliable engagement with the high-strength mortar.

[Effect] Since this invention is constructed and operates as described above,
According to the method for replacing underground piping according to the present invention, underground piping can be replaced by simply digging up the road at two points per construction area, and it is possible to replace the underground piping by simply digging up the road at two points per construction area.
It does not obstruct vehicle traffic. Moreover, the construction is relatively easy and does not require much time or cost. Furthermore, by replacing them, the capacity for water supply, gas supply, etc. is not reduced, but can even be increased, and old pipes that are no longer needed can be reused.

[Brief explanation of drawings]

1-1 to 1-3 are schematic cross-sectional views for explaining one embodiment of the method for replacing underground piping according to the present invention, dividing it into each stage of work progress. FIG. 2 is a schematic sectional view for explaining a modified embodiment of the invention,
It is a diagram partially showing the vicinity of the push-in pile and the push-in machine. 1... Push-in pile 2... Pull-out shaft 3...
Pushing machine 4... Pulling machine 5... Old piping
6... Locking protrusion 7... Steel bar
8...High strength mortar 9...New piping

Claims (1)

[Claims] The ground at both ends of one construction area where the pipes are buried will be excavated to form a push shaft and a pull shaft.A push machine will be installed in the push shaft and a pull machine will be installed in the pull shaft. A steel rod for extraction with many locking protrusions formed on the surface is inserted into the exposed old pipe, and high-strength mortar in a fluid state is poured and filled between the inner wall of the old pipe and the steel rod. , After solidification, a method for replacing underground piping involves gripping the tip of the steel rod with a puller and pulling out the old pipe into the pull-out shaft, and simultaneously pushing the new pipe from inside the pull-out shaft with a pusher.