JPH0686727B2 - Sleeve injection method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sleeve injecting method which is useful for improving the ground by injecting a chemical liquid, and particularly when applied to construction under pressured water.

[0002]

2. Description of the Related Art The sleeve injection method is a method of injecting a chemical solution by using a double pipe and a double packer to improve the ground, and has already many achievements. When such a sleeve injection method is applied to construction under pressured water, it is necessary to take measures to prevent the outflow of spring water and earth and sand generated from the mouth between drilling and installation of the double pipe.

Conventionally, various measures have been taken as measures for preventing the outflow of such spring water and earth and sand, but there are merits and demerits in that the construction is complicated or troubles are likely to occur during the construction.

The present invention has been made for the purpose of eliminating such conventional problems.

[0005]

According to the present invention, a casing is penetrated into a ground for improvement to a predetermined depth of the ground through a mouth seal member attached to the mouth of the ground, and the penetration of the casing is the casing. Drilling guide of the tip bit mounted on the tip of the tip so that it can be detached by remote control, and drilling guide of drilling water ejected from the nozzle with check valve opening at the tip of the tip bit. Muddy water containing pressured water generated during work is discharged to the outside through the supply and discharge ports provided on the mouth seal member while backflowing the outside of the casing, and then press-fitting and filling of the seal grout from the supply and discharge ports. After sealing the base of the drilled hole with, the outer tube of the sleeve injecting double tube is inserted into the casing, and the peripheral gap generated between the casing and the outer tube is inserted by the insertion. Seal with a sealing member attached to the inner peripheral wall of the tip portion, and then through a pouring port provided at the tip of the outer pipe and a press-fitting pipe connected to the pouring port, insert a seal grout into the drilled hole from a deep portion. While press-fitting and filling toward the shallow part, the casing is pulled out from the inside of the drilling hole while leaving the tip bead separated by external operation, then the press-fitting pipe is pulled out from the inside of the outer pipe, and then the double packer is placed inside the outer pipe. The present invention relates to a sleeve injecting method, which is characterized in that an inner tube with an insert is inserted and a chemical solution is injected through the inner and outer tubes in the usual manner.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following will describe one embodiment of the method of the present invention with reference to the accompanying drawings.

To carry out the method of the present invention, a mouth seal member (1), a casing (2), and double pipes (3a) and (3b) as a sleeve injection device are used.

The mouth seal member (1) serves to insert and guide the casing (2) into the ground with the mouth sealed as shown in FIG. 1, for example.
An inlet seal portion (4) is provided on the inlet side, and a supply port (5) for press-fitting and filling a seal grout and an outlet port (6) for spring water and the like are provided on the side portions. The supply port (5) is connected to a press-fit filling section (not shown) of a seal grout through an opening / closing cock (7) and a conduit (8).
On the other hand, the outlet (6) is provided with an opening / closing cock (9).

The casing (2) is provided with a tip bit (12) for ground excavation at the tip, and the bit (12) has a nozzle (14) with a check valve (13) as shown in FIG.
Is provided.

It is necessary that the tip bit (12) provided at the tip of the casing (2) can be appropriately separated from the casing (2) by remote control.

In the embodiment shown in FIGS. 9 to 12, the tip bit (12) can be inserted into and removed from the shaft hole (2a) at the tip of the casing (2) in the hollow shaft (12a). Inserted,
In this inserted state, the casing (2) can be locked or unlocked by rotating the casing (2) forward or backward at a predetermined angle.

In order to configure the lock mechanism, as shown in FIG. 9, an arc-shaped detent protrusion (1) having an angular width of, for example, 60 ° is formed on the outer peripheral surface of the hollow shaft portion (12a) of the tip bit (12).
5) are formed at two places with the center of the shaft in between. On the front end face (15a) of each detent protrusion (15) in the excavating rotation direction, a locking protrusion (1) having a predetermined angle width, for example, an angle width of 15 °.
6) is projected. Uniform projection (15) and projection (1
The angular width of 6) is shown in detail in FIG.

On the other hand, the shaft hole (2a) at the tip of the casing (2)
On the side, there is provided an anti-rotation groove (17) having an angular width slightly exceeding the sum of the angular widths of the projection (15) and the projection (16), for example, an angular width of 90 °. Are formed in two places by the above-mentioned projection ((1
5) and the protrusion (16) are fitted. A locking recess (18) that locks with the locking projection (16) is formed so as to open to the front end surface (17a) of the recess groove (17) in the excavation rotation direction. Although the locking recess (18) is formed over the entire length between the recessed grooves (17) (17) in FIG. 9, it may have at least an angular width corresponding to the locking projection (16). .

10 to 11 show the state of the lock state,
In this state, the locking projection (16) is engaged in the locking recess (18) and is prevented from coming off. In addition, the protrusion for stopping rotation (15)
The front end face (15a) in the excavation rotation direction of the above contacts the front end face (17a) in the same direction of the concave groove (17), so that the casing (2) and the tip bit (12) rotate integrally to enable excavation of the ground. become. As shown in FIG. 11, in the locked state, the locking protrusion (15) is locked between the rear end surface (15b) and the rear end surface (17b) of the concave groove (17). There is an interval (19) (see FIG. 10) having an angular width of, for example, 30 ° that exceeds the angular width of the projecting portion (16).

In FIG. 11, when the casing (2) is rotated in the direction opposite to the excavation rotation direction indicated by the arrow (20), 1
The locking protrusion (16) is rotated by 5 ° to 30 ° and the locking recess (1
8) It comes off and the lock is released. Then, in this state, as shown in FIG. 12, the tip bit (12) can be separated.

A water stop ring (21) is mounted on the inner peripheral surface near the tip of the casing (2), and the ring (21) is attached.
The inner diameter of is substantially equal to or smaller than the outer diameter of the outer pipe (3a) of the sleeve pipe, and if smaller, it is made of an elastic member such as rubber.

The outer tube (3a) constituting one part of the sleeve injection device has an injection port (22) as shown in FIG.
And a flexible sleeve (2) that covers the outside of the mouth (22).
3) is provided with an injection part (24), and the injection part (2
4) are provided at a plurality of positions at appropriate intervals in the pipe axis direction. Further, the tip is provided with a tip cone (25) with an inlet (26) as shown in an enlarged view in FIG.

On the other hand, the inner pipe (3b) is provided with a double packer portion (27) as shown in FIG. 8, and a strainer portion (not shown) is formed between the packers.

In carrying out the method of the present invention, the mouth seal member (1) is attached at a predetermined position on the ground surface to be improved according to a conventional method, and then the casing (2) is attached to the mouth seal part (1) of the member (1). It passes through 4) and is inserted up to the core boring mark (28) on the ground surface.

Next, when the rotation imparting device (not shown) is operated with the cock (7) closed and the cock (9) open, the rotation is given in the direction shown by the arrow (20) in FIG. The tip bit (12) rotates integrally with the casing (2) as shown in FIGS. Then, when the casing (2) is inserted into the ground in this state, the casing (2) guides the drilling of the tip bit (12) and the tip injection port (1) as the casing (2) is inserted.
4) The ground is drilled by the drilling guide of the drilling water ejected from 4), and this drilling is continued while the casing (2) is added until a predetermined depth is reached. Casing (2)
Outflow of spring water from the inside of the casing (2), which may be a concern at the time of replenishment, is prevented by the check valve (13) provided in the injection port (14).

The situation during the drilling operation is shown in FIG. During the drilling operation, drilling water, groundwater under pressure, etc. intensively flow back outside the casing (2) and are discharged from the discharge port (6). In FIG. 2, reference numeral (32) is the casing (2).
It is a jack for pulling out.

After finishing the drilling by the casing (2), as shown in FIG. 3, after closing the valve (9) of the discharge port (6), the drilling ( A water blocking agent (30) is press-fitted into the mouth portion (29a) of 29). Any water-stopping agent may be used as long as it has water-stopping properties, and for example, a cement-milk-based or water-glass-based water-stopping agent is suitable.

Next, the outer tube (3a) of the sleeve injecting device is inserted into the casing (2), and the casing (2) is rotated in the reverse direction, for example, 1
It is rotated at an angle of 5 ° to 30 °, and by this reverse rotation operation, the tip bit (12) is unlocked as is apparent from FIG. 11, and the tip bit (12) is separated by pulling out the casing (2). Ready to get.

Therefore, in this state, as shown in FIGS. 4 to 5, the press-fitting pipe (31) is inserted into the outer pipe (3a), and the tip of the press-fitting pipe (31) is connected to the tip cone of the outer pipe (3a). (25)
Connection to the inlet (26).

In the state shown in FIGS. 4 to 5, the press-fitting pipe (3
When the jack (32) is actuated and the casing (2) is gradually pulled out while the seal grout is press-fitted from 1) through the injection port (26) connected thereto, the outer pipe (3a) is gradually pulled out as the casing (2) is pulled out. A seal grout is injected and filled into the hole (29) around the hole. The tip bit (12) is in a separable state and does not accompany the casing (2) withdrawn. This seal grout is press-fitted into the hole (2
It is carried out with a pressure such that the residual mud in 9) is pushed into the ground. Outer tube (3a) during press-fit filling operation of seal grout
The outflow of the seal grout between the casing and the casing (2) is
It is prevented by the water stop ring (21) provided in the casing (2).

Seal grout (33) in the drilled hole (29)
Since the casing (2) is pulled out while injecting and filling, the pulling resistance is small and the pulling out operation is easy.

After the operation of drawing out the casing (2) to the mouth and injecting and filling the seal grout (33) into the drilled hole (29) are completed, the press-fitting rod (31) is drawn out and then collected. As shown in FIG. 3, the inner pipe (3b) and the existing outer pipe (3a) are used to make a mouth (29) of the hole (29).
The water-stopping agent (30) was injected and filled into the a) again, and the mouth portion (29
Strengthen the waterproofness of a). This waterproofing enhancement is necessary for removal of equipment such as the mouth seal member (1) and the jack (32).

Grouting agent (33) filled in the hole (29)
After curing and solidifying the outer tube, as shown in Fig. 7, the outer tube (3
After removing all the equipment except a) and installing the seal flange (34) at the mouth instead, as shown in Fig. 8, using the inner pipe (3b), cracking and water pushing were performed as usual. After that, the ground is improved by grout injection.

After the ground improvement, the inner pipe (3b) is pulled out and recovered, and the outer pipe (3a) is buried.

As shown in FIG. 7, when the outer pipe (3a) is projected to the ground longer than necessary, the unnecessary portion may be cut and removed.

In the embodiment, the ground improvement from the vertical direction is explained, but even if it is applied to the ground improvement from the horizontal direction,
Substantially the same effect is obtained.

[0032]

[Effect] According to the method of the present invention, the spring water (including pressurized water) is completely stopped during the process from drilling to installation of the outer pipe, and the seal grout is provided inside the drilling hole. Since the casing is pulled out while pouring and filling from the deep part to the shallow part, the pulling resistance is much smaller than the case where the casing is pulled out after the filling and filling of the seal grout, and the pulling work becomes easier, and the seal grout layer There is no risk of breaking the seal and a good quality seal grout layer can be formed.

[Brief description of drawings]

FIG. 1-8 is an explanatory view showing the method of the present invention in the order of steps.

FIG. 9 is a perspective view of a lock mechanism applied to the tip bit.

FIG. 10 is a vertical cross-sectional view when locked.

11 is a cross-sectional view taken along line 11-11 of FIG.

FIG. 12 is a vertical cross-sectional view when unlocking.

FIG. 13 is a partial vertical cross-sectional view of an outer tube.

[Explanation of symbols]

 1 mouth seal member 2 casing 3a outer pipe 3b inner pipe 4 mouth seal part 5 supply port 6 discharge port 7 cock 8 conduit 9 cock 12 tip bit 13 check valve 14 injection port

Claims (1)

[Claims] 1. A casing is penetrated into a ground for improvement through a mouth seal member attached to the mouth of the earth to a predetermined depth of the earth, and the penetration of the casing can be cut off at the tip of the casing by remote control. Included in the tip bit of the tip bit and the guide for drilling water ejected from the injection port with a check valve that opens at the tip of the tip bit, and also includes pressurized water generated during penetration work. Muddy water is discharged to the outside from the supply and discharge ports provided in the mouth seal member while backflowing on the outside of the casing, and then the seal grout is press-fitted from the supply and discharge ports to seal the mouth of the drilling hole. After applying, 2 for sleeve injection into the casing
The outer pipe of the heavy pipe is inserted into the free pipe, and the peripheral gap generated between the casing and the outer pipe by this insertion is sealed by a seal member attached to the inner peripheral wall of the tip portion of the casing, and then the tip of the outer pipe. Through the injection port provided in and through the press-fitting pipe connected to the injection port, while the seal grout is press-fitted from the deep part to the shallow part in the drilled hole, the casing,
Withdrawing from the inside of the drilled hole leaving the tip bead separated by external operation, and then removing the press-fitting tube from the outer tube, inserting the inner tube with double packer into the outer tube,
The sleeve injection method is characterized in that the chemical solution is injected through the inner and outer tubes in the usual manner.