JPH0418083B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a steel material equipped with a grout injection pipe used in a method of constructing an impermeable wall by injecting grout while pulling out the steel material that has penetrated into the soil.

A known construction method for impermeable walls is to penetrate H-shaped or I-shaped steel materials into the soil, and then pull them out while injecting grout to create walls. It is used as a simple retaining wall.

In this type of construction method, a grout injection pipe that is normally provided in the steel material is used.In order to prevent the intrusion of earth and sand that occurs when the steel material is driven into the grout injection pipe, a cone is loosely fitted at the tip of the grout injection pipe, and when the steel material is pulled out, The cone was left in the soil, and the tip of the hollow pipe was opened and grout was injected.

However, when the grouting pipe used in this method becomes deep or the ground is hard, the cone or hollow pipe may deform, making it impossible to remove the cone, or causing damage. grouting becomes impossible.

This invention has been made in view of the above-mentioned conventional problems, and its purpose is to:
To provide a steel material equipped with a grout injection pipe that can reliably inject grout even when the steel material is driven deep or on hard ground.

In order to achieve this object, the present invention provides a steel material that is penetrated into the soil and then pulled out, the steel material having a grouting pipe for injecting grout for constructing an impermeable wall when the steel material is pulled out. This grout injection pipe consists of a top-shaped cone fixed to the lower part of the steel material, an inner pipe erected from the top of the cone to the upper part of the steel material, and an inner pipe extending outward from the inner pipe. It consists of a hollow cylindrical outer tube which is disposed and can be moved up and down relative to the inner tube and forms a grout supply path between the inner tube and the outer tube. When descending, the lower opening of the outer tube comes into contact with the cone and is closed,
It is characterized by forming a gap for grout injection between the cone and the cone when raised relative to the inner tube.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show an embodiment of a steel material equipped with a grout injection pipe according to the present invention.

A steel material 10 equipped with a grout injection pipe shown in the same figure,
10... are connected laterally and penetrated into the water stop layer or hard ground in the soil until the lower end reaches it, and then the steel material 10 at the end is pulled out upward.

The steel material 10 has a shape in which a hollow cylindrical male fitting part 14 is fixed to one end of a flat base 12, and a hollow cylindrical female fitting part 16 with a slit 15 is fixed to the other end, These fitting parts 14, 16
is fitted with another adjacent steel material 10 to connect it in the lateral direction.

Further, on the outer surface of the base 12 of the steel material 10,
A pair of grout injection pipes 1 along this
8 and 18 are mounted diagonally.

Details of the grout injection pipes 18, 18 are shown in FIG.

The grout injection pipe 18 has a double structure consisting of a solid cylindrical inner pipe 20 and a hollow cylindrical outer pipe 22.

The outer tube 22 is secured to the base 12 of the steel material 10 with bands 23 at appropriate locations so that it can move up and down relative to the inner tube 20, and a generally top-shaped cone 24 is fixed to the tip of the inner tube 20. This cone 2
4 is located near the lower end of the steel material 10 and is firmly fixed to the base 12.

An annular packing 26 is interposed between the upper end of the outer tube 22 and the outer peripheral surface of the inner tube 20, and an annular collar piece 28 is provided on the outer surface of the outer tube 22.
The inner tube 20 extends further upward than the packing 26, a screw is provided around the outer periphery of this extended portion, and an enlarged head 25 is formed at the top.

Further, a stopper 30 is installed between the upper end of the outer tube 22 and the enlarged head 25 to be screwed into the screw.

The grout injection pipe 18 configured in this way is
When the stopper 30 is attached so that its upper end projects upwardly than the upper end of the steel member 10, and the lower end of the stopper 30 is in contact with the upper end of the outer tube 22, the lower end of the outer tube 22 is in close contact with the cone 24, While closing the inside of the tube 22, the stopper 30 is rotated to position it upward, and the outer tube 22 is closed, for example, by the collar piece 28.
The outer tube 22 can be lifted by attaching a wire to it and pulling it up with a crane, or by inserting a jack between the collar piece 28 and the upper end of the base 12 of the steel member 10.
A gap 32 is formed between the lower end of the cone 24 and the cone 24 .

Note that a member indicated by the reference numeral 34 in the figure is a grout injection port communicating with the outer tube 22.

Grout injection is performed in the following steps.

First, before pulling out the steel material 10, move the stopper 30 upward and pull up the outer tube 22.
supplying grout through the inlet 34 of the outer tube 22;
After that, the steel material 10 is pulled out.

The grout supplied to the injection port 34 is
When the steel material 10 is pulled out through the gap 32, it is injected into a space formed at the lower end of the steel material 10 with the same cross-sectional shape as the steel material 10.

When grout is injected using the method described above, when penetrating the steel material 10 into the soil, the grout injection pipe 1
Since the outer tube 22 of No. 8 is closed by the cone 24, surrounding earth and sand are completely prevented from entering the inner tube, and as a result, grout can be easily and reliably injected.

In addition, since the cone 24 at the tip of the injection pipe 18 is firmly fixed to the steel material 10, it will not be damaged when driving the steel material 10, making it possible to drive the steel material 10 at great depths or into hard ground. .

FIG. 3 shows another embodiment of the grouting pipe 18, and only its features will be described below.

That is, in this embodiment, a case is illustrated in which a water-shielding wall is formed using a two-component type grout, and the inner tube 20 is formed into a hollow cylindrical shape like the outer tube 22, and an outer wall is formed at the tip of the inner tube 20. A plurality of through holes 35 are formed that communicate with the gap 32 formed when the tube 22 is pulled up, and an injection port 36 that communicates with the inner tube 20 is provided at the upper end.

In this embodiment, liquids A and B, which harden in a relatively short time when mixed, are placed in separate injection ports 3.
4 and 36, and are mixed as they are discharged outward through the gap 32.

Even if the grout injection pipe 18 configured in this manner is used, the same effects as in the above embodiment can be obtained, and since the liquids A and B are supplied separately until they reach the gap 32, the liquids A and B are hardened. Blocking of the injection tube 18 can be prevented.

FIG. 4 shows yet another embodiment of the grout injection pipe 18, and only its features will be described below.

That is, in this embodiment, a ring-shaped protrusion 30a that protrudes inward is formed at the lower end of the stopper 30, and a recess 22a that fits into the ring-shaped protrusion 30a is formed on the outer surface of the upper end of the outer tube 22. A handle 30b is provided on the outer surface.

Even when using the grout injection pipe 18 configured in this way, the same effects as in the above embodiment can be obtained, and the vertical movement of the stopper 30 is controlled by the handle 3.
This can be easily done by rotating 0b.

As explained in detail in the embodiments above, the steel material equipped with the grout injection pipe according to the present invention prevents the intrusion of earth and sand from making injection difficult, as well as preventing the grout from entering at great depths. Even when forming impermeable walls on hard ground, grout can be poured reliably without the difficulty of leaving cones in place as with conventional methods, improving the efficiency of grouting work and the reliability of construction. do.

In addition, excellent effects can be obtained, such as the ability to inject two-component grout in a well-mixed state.

[Brief explanation of drawings]

1 and 2 show one embodiment of the present invention, FIG. 1 is an overall explanatory diagram thereof, and FIG.
It is a sectional view of the main part of the figure. FIG. 3 is a sectional view showing another embodiment of the grout injection pipe. FIG. 4 is a sectional view of a main part showing still another embodiment of the grout injection pipe. 10... Steel material, 18... Grout injection pipe, 20
...Inner pipe, 22...Outer pipe, 32...Gap part.

Claims (1)

[Scope of Claims] 1. A steel material that is penetrated into the soil and then pulled out, which is equipped with a grout injection pipe for injecting grout for constructing an impermeable wall when the steel material is pulled out, and the grout is The injection pipe consists of a top-shaped cone fixed to the lower part of the steel material, an inner pipe erected from the top of the cone to the upper part of the steel material, and an inner pipe disposed outside of the inner pipe. It consists of a hollow cylindrical outer tube that can be moved up and down relative to the inner tube and forms a grout supply path between it and the inner tube, and when the outer tube is lowered relative to the inner tube, A grout characterized in that a lower opening of the outer tube is closed by contacting the cone, and a gap for grout injection is formed between the outer tube and the cone when raised relative to the inner tube. Steel material with injection tube. 2. A steel material equipped with a grout injection pipe according to claim 1, wherein the grout is a two-component grout that is hardened by mixing, and the supply path contains one of the grout components. On the one hand, the inner tube is formed into a hollow cylindrical shape so that the other grout component can be supplied,
The lower part of the inner tube is provided with a through hole for mixing the grout components supplied from the inner tube and the outer tube at a position facing the grout injection gap. Steel material with grouting pipe.