JPS6117968B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ground injection method.
Conventionally, when injecting hardening material into the ground, it is necessary to use a casing if the geology is soft and the injection packer cannot be set. Therefore, if a cable pipe is used for the casing, it becomes difficult to remove the cable pipe exposed on the face surface when excavating hardened ground, which poses a problem. In other words, in the case of mechanical excavation, the steel pipe is hard and the pit at the tip of the excavation machine is severely worn, and its fragments get mixed into the excavation and affect other equipment, and when excavating using the blasting method, many The steel pipes must be gas cut one by one, which requires a considerable amount of work time.

Furthermore, if a normal pipe is used as the casing, there is a risk that the casing will rotate when drilling the injection port.

This invention was developed in view of the above circumstances, and details thereof will be explained below with reference to illustrated embodiments.

First, casing 1 used in this invention
To explain this, the casing 1 is made of a synthetic resin pipe, and a continuous or multiple protrusions 2 are formed on the outer periphery of the casing 1. In particular, when manufacturing, the main body is made of a synthetic resin reinforced with glass fibers that is molded by filament winding, and a thermosetting resin such as unsaturated polyester resin or epoxy resin is used around the outer circumference of the belt-shaped material such as cotton fabric tape or spindle tape. The protrusion 2 is integrally molded with the main body, and is formed by winding the impregnated material in a spiral, and then spirally wrapping a synthetic resin strip such as a protrusion that is cured simultaneously with the curing process of the main body. be.

Further, a joint is formed with a male thread 3 at one end of the casing 1 and a female thread 4 at the other end. This casing has an inner diameter of 60 to 80 mm and a length of about 3.5 m.

During construction, a borehole B with a diameter of around 100mm and a length of approximately 10m was drilled in the ground A, the inside of the borehole B was cleaned, three casing pipes were connected, and the total length was 10.5m, and the borehole B was inserted into the borehole B. Temporarily fix it. Next, an injection pipe 6 with a packer 5 attached to the outer periphery of its tip is inserted and fixed, and a hardening material made of cement, water glass, etc. is injected. The hardened material injected from the tip of the injection pipe 6 flows into the gap between the casing pipe 1 and the hole wall of the borehole B, and is injected to the mouth of the borehole B. This injection is performed intermittently, and in the case of cement/water glass, it solidifies in about 30 to 60 seconds, and the casing pipe 1 is fixed in the borehole. Since the casing pipe 1 has a protrusion 2, it is fixed so that it does not rotate completely.

Next, the injection pipe 6 inside the casing pipe 1 is pulled out, a boring machine is inserted to drill a hole to the required depth, the boring machine is then pulled out, and a ground hardening material such as a chemical solution is poured into the ground A using the injection pipe inserted into the casing. Inject and harden.

When excavating the ground A, the casing pipe 1 is left as is and excavated together with earth and sand.

This invention has the above-mentioned structure, and since a synthetic resin pipe is used for the casing pipe, there is no damage to the pick during excavation of the ground, there is less wear on the pick, and it is also suitable for other equipment such as earth and sand transport equipment. No impact.

In addition, there is a protrusion formed by spirally wrapping a synthetic resin band around the outer periphery of this casing pipe.
A hardened material is injected into the gap between the casing and the borehole wall and is fixed in the ground, which serves as a guide when a boring machine is inserted to drill the hole.It also reliably prevents the borehole from collapsing and stabilizes the ground. This facilitates the drilling of holes and the subsequent injection of soil hardening materials. In addition, the ground excavation efficiency is improved without the need to remove the casing pipe.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a partial cross section of the casing pipe, and FIG. 2 is a cross sectional view showing an outline of the construction process. 1...Casing pipe, 2...Protrusion, 3...
Male thread, 4...Female thread, 5...Packer, 6...
injection pipe. A...ground, B...borehole.

Claims (1)

[Claims] 1. A borehole is drilled in the ground, and then a casing made of a synthetic resin pipe with protrusions formed by spirally wrapping a synthetic resin strip around its outer periphery is inserted into the borehole, and then a casing is inserted into the borehole, and then a casing is inserted into the borehole, and a casing made of a synthetic resin pipe is then formed around the outer periphery of the tip. After inserting the injection pipe with the attached injection pipe into the casing and injecting a hardened material into the gap between the casing and the hole wall of the borehole to fix the casing in the borehole, the injection pipe is pulled out from inside the casing and then inserted into the casing. A boring machine is inserted into the casing to drill a hole to a required depth, and then the boring machine is removed from the casing, and then the ground preparation material is injected into the ground using an injection pipe that is reinserted into the casing to harden the ground. Ground injection method.