JPH0119486B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chemical injection device for civil engineering used in a method of injecting chemical liquid to strengthen soft ground.

During civil engineering work such as tunnel construction, when the ground is soft, a chemical solution is injected into the ground before excavation work begins in order to prevent accidents such as cave-ins and to make the excavation work easier. It is normal to perform excavation work after the ground has hardened, and in general, the work of injecting the chemical liquid is performed by boring several places in the ground where the chemical liquid is to be injected, inserting a casing pipe, and then After inserting the chemical liquid injection pipe into the tank and sealing the gap between the ends of the casing pipe and the chemical liquid injection pipe, a chemical liquid injection machine is set, and the chemical liquid such as cement milk, water glass, etc. is force-fed into the chemical liquid injection pipe by the press-fitting machine. The chemical solution is then injected into the ground from the tip of the injection pipe and hardened, thereby hardening and strengthening the ground.

Conventionally, the chemical injection pipes used in the above chemical injection work include steel pipes, synthetic resin pipes,
Glass tubes etc. are bonded together, but when inserting the tube after boring, if there is a protrusion in the borehole, it may get caught on the protrusion, or the joint of the chemical injection tube may be inserted into the protrusion. It was difficult to do the work efficiently because the work would take a long time because the work would get stuck and become stuck.

The present invention has been made for the purpose of providing a chemical liquid injection device that can solve the problems of the prior art as described above, and its configuration is such that the chemical liquid is inserted into a borehole provided in the ground where the chemical liquid is to be injected. A chemical liquid injection guide tube with a medical liquid injection tube with a sealed tip fitted in a folded state is inserted into an outer cylinder having an outer diameter that allows loose insertion into the casing pipe, and the rear part of the chemical liquid injection guide tube is inserted into the outer cylinder. It is characterized by being supported at the rear.

Next, an example of implementation of the present invention will be explained with reference to the drawings.

The figure shows the chemical injection device of the present invention set in a casing pipe inserted into a borehole. In the figure, G is the ground where the chemical liquid is to be injected;
B is a borehole provided in the ground G, C is a casing pipe inserted into the borehole B, 1 is an outer cylinder having an outer diameter that can be loosely inserted into the casing pipe C, 2 is a chemical injection guide pipe, and 3 is a tip Seal the part 3
a chemical solution injection tube, 4 is a flange provided at the rear of the chemical solution injection guide tube, 5 is a support section provided at the rear end of the outer cylinder 1, which is brought into contact with the flange 4 of the chemical solution injection guide tube 2, and the bolt The guide tube 2 is supported by the outer cylinder 1 by tightening them both with a screw 6, and the drug solution injection guide tube 2 is provided with a flange-shaped head 2a at its tip for preventing backflow of drug solution.
A fin 2b for regulating the flow of the tube 3 is formed integrally with the tube 3, and the drug solution injection tube 3 is fitted into the bellows-like folded state, and the rear end of the tube 3 is fixed to the rear part of the guide tube 2. It has been done.

Numerals 7 and 8 are sealers for sealing a gap formed between the casing pipe C and the rear end of the outer cylinder 1.

The chemical liquid injection device of the present invention is constituted by 1 to 6 above, and as shown in the figure, it is set in a casing pipe C, and a chemical liquid injection machine (not shown) injects the chemical liquid into the injection guide pipe. 2, the liquid medicine passes through the guide tube 2 and is forced out from its tip, pressing the liquid injection tube 3 and moving forward. At this time, the folded portion of the tube 3 sequentially When the seal 3a at the tip reaches the tip of the borehole B and the pressure inside the tube 3 increases, the tube 3 expands in the circumferential direction and seals the area around the outer periphery of the borehole B. When the pressure inside the tube 3 exceeds a certain pressure value due to close contact with the mountain, the seal 3a etc. will break and the injection of the chemical into the ground G will begin. If there is a crack or soft ground in the middle part, the tube 3 corresponding to the crack or soft ground breaks and the chemical solution leaks out, and the chemical solution is injected into the crack or soft ground section.
In the above chemical liquid injection work, the chemical liquid injection guide tube 2
The head 2a and fins 2b provided at the tip of the tube serve to prevent the backflow of the drug solution and to make the drug solution injection tube 3 run smoothly when the drug solution injection tube 3 is extended.

In the above embodiment, the case where the device of the present invention is inserted into the casing pipe C has been described, but the present invention is not limited to this, and the device of the present invention may be inserted directly into the boring B. good. In addition, in the device of the present invention, a cap 9 is detachably attached to the tip of the outer cylinder 1, and when not in use, the cap 9 is left attached to protect the internal chemical injection tube 3, etc., and when in use, the cap 9 is attached. It may be removed and inserted into the casing pipe C or the borehole B. By doing so, the device of the present invention becomes a cartridge type device, which is extremely convenient not only in use but also in transportation and storage.

The chemical injection work using the device of the present invention uses an outer cylinder, a chemical liquid injection guide tube inserted into the outer cylinder, and a soft chemical liquid injection tube instead of a conventional chemical liquid injection tube such as a steel pipe or a synthetic resin pipe, and the tube is inserted into the guide tube. When it is attached in a folded state and a chemical solution is injected into the guide tube, the chemical solution will flow into the tube, and the tube will expand to move by itself due to the injection pressure of the chemical solution, and the tip of the tube will be inserted into the borehole. When the tip of the tube is reached and the pressure inside the tube increases, the tube expands in the circumferential direction and eventually ruptures, allowing the chemical solution to be injected into the ground, making the chemical injection work extremely efficient. Not only is it possible to inject drugs easily, but it is also possible to inject drugs into cracks, etc., where it was not possible to sufficiently inject drugs with conventional drug injection devices.

Therefore, the chemical liquid injection device of the present invention is suitable as a chemical liquid injection device used for injecting chemical liquid into soft ground to strengthen the ground prior to tunnel construction work or the like.

[Brief explanation of drawings]

FIG. 1 is a longitudinal side view of an embodiment of the present invention, and FIG. 2 is a longitudinal side view of the device set in a borehole for use. G...Ground, B...Borehole, C...Casing pipe, 1...Outer cylinder, 2...Chemical solution injection guide tube, 3...Chemical solution injection tube, 7, 8...Pack car.

Claims (1)

[Scope of Claims] 1. A chemical liquid injection tube with a sealed tip is fitted in a folded state into an outer cylinder having an outer diameter that can be loosely inserted into a casing pipe to be inserted into a borehole formed in the ground where the chemical liquid is to be injected. A chemical liquid injection device for civil engineering, characterized in that a chemical liquid injection guide tube is inserted thereinto, and a rear part of the chemical liquid injection guide tube is supported by a rear part of the outer cylinder. 2. The device according to claim 1, wherein a cap is detachably attached to the tip of the outer cylinder.