JPH0730572B2 - Method of moving and correcting underground buried pipes and oscillating device used in the method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Object of the Invention" (Field of Industrial Application) The present invention relates to a method for moving and correcting a pipe buried in the ground without excavating the soil, and a vibrating device used for the method. In particular, the present invention relates to a construction method and device suitable for correcting movement of a pipe having a relatively large diameter.

(Prior Art) Conventionally, in order to correct the slack of the underground buried pipe due to uneven subsidence of the ground, etc. A so-called grout method is known in which a solidified body made of a mixture of cement and water glass is injected into the lower side of the pipe to solidify it, thereby pushing up the slack portion of the pipe.

(Problems to be Solved by the Invention) However, in the above-mentioned grout method, there is a fundamental difficulty that it is difficult to set the optimum amount of the injection material for the movement correction of the pipe.

The present inventor has variously researched other construction methods in place of the above-mentioned clout construction method for the movement correction construction method of the buried pipe, and as a result, when burying the pipe in the ground, the earth and sand are backfilled around the pipe, and therefore, Since a sediment layer is generally formed around the buried pipe, it was found that the buried pipe can be moved and corrected by utilizing the fluidization phenomenon of the sediment layer.

As a result of research on the fluidization phenomenon of the saturated sand layer triggered by the investigation of the cause of the so-called Niigata earthquake collapse bridge, the cause of the fluidization of sediment is roughly explained as follows.

Generally, loosely accumulated sand becomes dense when subjected to vibration,
Conversely, when sand with a high density loosens when it is subjected to vibration, but when sand with a density lower than the void ratio (critical void ratio) in the limit state of this density is saturated with water, it undergoes vibration. , The pore water pressure rises to reduce the pores, and the contact pressure (effective stress) between particles becomes smaller, so that the shear resistance decreases. When this shear resistance almost disappears, the sand becomes fluid ( Fluidization of sand), a heavy object on the surface side of the sand gradually sinks, and a lightweight object buried in the sand is said to float.

Therefore, it is possible to move the pipe by causing a fluidization phenomenon in the earth and sand layer formed around the buried pipe.

A first object of the present invention is to provide a construction method for moving and correcting a buried pipe by utilizing the fluidization phenomenon of sand as described above, and a second object of the present invention is to implement the construction method. It is to provide a vibrating device to be used.

"Structure of the Invention" (Means for Solving Problems) In the underground buried pipe movement correction method according to the present invention, an oscillating device is installed in a pipe buried in the ground, and the oscillating device is used to form a pipe. By applying vibration, the sediment around the pipe is vibrated to generate fluidization phenomenon in the soil saturated with water, and a heavy object in the sediment sinks and a light object floats. It is a method of moving and correcting the pipe body, and the oscillating device of the present invention includes a frame having plate spring-shaped legs, an oscillating device main body fixed to the frame,
An adjusting arm is provided which extends from the frame in an extendable and contractable manner, and has a tip end portion provided with a contact member for contacting the top end of the tube.

When carrying out the construction method of the present invention, water can be injected through a pipe built from above in order to make the earth and sand layer around the buried pipe a saturated sand layer.

(Operation) Since earth and sand are usually backfilled around the pipe buried in the ground, an oscillating device is installed inside the buried pipe whose movement is to be corrected, and the pipe is vibrated by the oscillating device. This gives vibration to the sediment around the pipe. The geological condition of the part where the pipe is buried differs depending on the location.In the case of the geological condition that the soil around the pipe is not saturated with water, build a pipe from the ground and supply water through the pipe. As a result, the soil is made to absorb water sufficiently and a state saturated with water is generated.

When vibration is applied to the earth and sand saturated with such water through a pipe, the earth and sand are fluidized, and the embedded pipe, which is a hollow body, is a lightweight object in the earth and sand and gradually floats up. The slack in the tube is corrected.

(Example) The Example of this invention is described based on drawing.

In the figure, A is an underground buried pipe such as a water pipe, but around the underground buried pipe A, earth and sand are backfilled to form a sediment layer B. The oscillating device 1 is installed in the buried pipe A, and vibration is applied to the pipe A by the oscillating device 1 to vibrate the sediment around the pipe to fluidize the soil saturated with water. Generate.

The volume of the pipe A in the earth and sand is large, but the pipe is a hollow body, so it is a light material in the earth and sand. Therefore, the action in the fluidization phenomenon of the earth and sand, that is, the heavy object sinks and the light object floats. By the action, the pipe A is floated up and the slack can be corrected. Since the level of the float-corrected pipe A can be easily detected, the vibration by the vibration oscillating device 1 is stopped in a state where the pipe is corrected to a predetermined position.

The geological condition of the part where the pipe A is buried differs depending on the location. In the case of the geological condition that the sediment layer B around the pipe is not saturated with water, build the pipe P from the ground and By supplying water W through the water, the earth and sand are made to absorb water sufficiently and a state saturated with water is generated.

As shown in FIG. 2, the oscillating device 1 includes a frame 2 having leaf spring-like legs 3, an electric oscillating body 4 fixed to the frame 2, and an elevation adjustment from the frame 2. It is constituted by an adjusting arm 5 which extends freely and is provided with an abutting member 6 which abuts against the top end of the tube at its tip.

Explaining the configuration of the above-mentioned vibration generating device 1 in detail, leaf spring-like legs 3 are provided in parallel with the frame 2, and casters 7 are attached to the respective tip ends of the legs 3 to move in the pipe. It is convenient when driving. In the embodiment, as the constitution of the adjusting arm 5, the hydraulic cylinders 8 are arranged on both front and rear sides of the frame 2, and the two rods 9 are arranged.
A connecting member 10 is provided in between, and an abutting member 6 made of a cushion material such as wood is attached to the connecting member 10.

As shown in FIG. 1, when the pipe A in which sagging or the like has occurred is lifted up to the position of the level L and corrected, the electromotive vibration device 1 configured as described above is moved and moved inside the pipe by a wire or the like. Then, when the adjusting arm 5 is jacked up hydraulically via the hose 11, the contact member 6 comes into pressure contact with the top end of the pipe. By doing so, it is possible to accommodate tubes having different inner diameters.

In this state, when electricity is applied to the vibrating body 4 to generate vibration, the pipe A vibrates through the leaf spring-shaped leg portion 3 and the contact member 6, and thus the pipe A is formed around the pipe A. Vibration is applied to the existing sediment layer B. Since the earth and sand layer B is saturated with water, fluidization occurs in the earth and sand, and a heavy object C such as a stone in the earth and sand sinks and the pipe A, which is a lightweight object, gradually rises.

It should be noted that the above-described vertical adjustment of the adjustment arm 5 can use not only jack-up by hydraulic pressure but also other appropriate means.

[Advantages of the Invention] According to the movement correction method for an underground buried pipe according to the present invention, the vibrating device is installed inside the buried pipe to be moved and corrected, and the vibrating device vibrates the pipe to thereby vibrate the pipe periphery. The pipe can be levitation-corrected by vibrating the earth and sand to cause a fluidization phenomenon in the earth and sand that is saturated with water.
Therefore, of course, it is not necessary to carry out a large excavation work to move and correct the pipe, and it is not necessary to inject a large amount of solidification material as in the conventional grout method, and the pipe move correction work can be performed quickly. .

[Brief description of drawings]

FIG. 1 is a sectional view showing a situation of an underground buried pipe to be lifted and corrected, FIG. 2 is a sectional view of the pipe showing a state where an oscillating device is installed, and FIG. 3 is a perspective view showing the oscillating device. . A: underground pipe, B: earth and sand layer, P: pipe 1: oscillating device, 2: frame, 3: leg part 4: oscillating body, 5: adjusting arm, 6: contact member 7: caster, 8: Hydraulic cylinder, 9: Rod

Claims (4)

[Claims] 1. A soil and sand in a state of being saturated with water by installing a vibrating device in a pipe buried in the ground, and vibrating the pipe by the vibrating device to vibrate the sediment around the pipe. A movement correction method for underground pipes, characterized in that the pipe body is moved and corrected by utilizing the action of causing a fluidization phenomenon to occur and sinking a heavy object in the earth and sand and lifting a light object. 2. The method according to claim 1, wherein water is injected into the earth and sand around the pipe to be moved and corrected through a pipe built from the ground so that the earth and sand is saturated with water. The moving correction method described in item 1. 3. When a pipe buried in the ground is vibrated, the sand around the pipe is vibrated to cause a fluidization phenomenon in the sand that is saturated with water, and It is a vibrating device that is installed in the pipe to give vibration to the pipe, which is used in the method of moving and correcting the pipe main body by utilizing the action of sinking and floating a light object. A frame provided with the frame, a vibrating body main body fixed to the frame, and an adjusting arm extending from the frame so as to be adjustable up and down and provided with an abutting member for abutting against the top end of the pipe at its tip. An oscillating device characterized by. 4. An oscillating device according to claim 3, wherein the legs are provided with casters for movement.