JP2001303550A - Method for cutting off water at intersection of soil cement continuous wall - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent leaks due to a cold joint at the intersection of intersecting soil cement continuous walls constructed at different times. SOLUTION: A joint hole 5 filled with a solution containing a non-setting water-impermeable material is formed in advance at the intersection of a previously constructed continuous wall 41 and another continuous wall 44 constructed afterwards, and the ends of the intersecting continuous walls 41 and 44 are interconnected within the joint hole 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of stopping water at a crossing point of a continuous soil cement wall to prevent water leakage due to a cold joint at the crossing point of the continuous wall of the cement cement which is constructed with a time difference. .

[0002]

2. Description of the Related Art An endless chain having a cutting blade is circulated around a cutter post, and the cutter post is traversed underground while discharging solidified material liquid into the ground. For example, when the continuous wall of soil cement is built around a box shape as a retaining wall or a water impervious wall, or crossed with an L shape, etc., or a new continuous wall is built by crossing an existing continuous wall. In the case of, in order to prevent water leakage from the outside of the structure consisting of the continuous wall at the intersection of the continuous wall that is built earlier and the continuous wall that is built later,
Continuity is required.

However, in the case where the continuous wall is made to go around in a box shape, when the construction of the last constructed continuous wall is completed, the construction end portion should be continuous. Since the starting portion has begun to solidify, the intersection of the preceding continuous wall and the subsequently constructed continuous wall becomes a cold joint, and the continuity of the soil cement cannot be ensured.

[0004] The same can be said for the case where the continuous wall intersects in an L shape or the like, or the case where a new continuous wall intersects an existing continuous wall.

Conventionally, no special countermeasures have been taken for cold joints at the intersections of soil cement continuous walls constructed with such a time lag. Only measures to control water leakage to the extent that does not hinder the operation are taken.

At the intersection of a continuous wall constructed later and a preceding continuous wall, an endless chain is constructed so as to cut into the preceding continuous wall for connection with the preceding continuous wall. As shown in FIG. 7- (a), it is conceivable that the continuous wall, which is preceding and solidified, receives a pushing force from the cutter post, so that a crack is formed on that side. If there is a crack, water leakage at that part becomes a problem.

In view of the above background, the present invention proposes a method for preventing water leakage due to a cold joint of a continuous soil cement wall constructed with a time difference.

[0008]

According to the present invention, at the intersection of a continuous wall constructed before and a continuous wall constructed later,
A soil constructed with a time difference by forming a joint hole previously filled with a liquid containing a non-consolidating water-impermeable material and connecting ends of continuous walls intersecting in the joint hole. Prevents cold joint leakage at the intersection of cement continuous walls.

At the intersection of the continuous walls, FIG.
As shown in the above, since the construction end portion of the other is cut into one of the continuous walls built earlier, if the preceding continuous wall is solidified, The connecting surface becomes a cold joint, and groundwater infiltrates from the outside of the structure through the connecting surface as shown by the arrow.

On the other hand, in the present invention, as shown in FIG. 6A, ends of adjacent continuous walls are connected at a joint hole filled with a liquid containing a non-consolidating water-impermeable material,
Since the connecting surface of the two-way continuous wall is located in the water-impermeable material, the groundwater intrusion path is blocked, so that water leakage at the intersection is prevented. Even if water invades along the surface of the continuous wall and the connecting surface, the water passage path is (b)
In this case, the apparent hydraulic conductivity becomes smaller.

[0011] In addition, since a joint hole having a diameter larger than the width of the continuous wall is formed at the intersection of the preceding continuous wall and the continuous wall to be subsequently formed, the pushing force from the cutter post is temporarily reduced. Therefore, even if the preceding continuous wall has a crack, the problem of water leakage due to the crack is eliminated because the joint hole surrounds the location where the crack occurs. In the drawings, the joint hole is illustrated as having a cylindrical shape, but the cross section of the joint hole may be rectangular or another shape.

Alternatively, if a solidifying material is added to the liquid containing the water-impermeable material to solidify the joint hole, the liquid can be mixed as shown in FIG.
Even if the joint hole does not have a diameter larger than the width of the continuous wall as shown in the figure, the joint hole connecting to the preceding continuous wall is Since sufficient resistance is exhibited, the occurrence of cracks in the preceding continuous wall is prevented.

In this case, the joint between the solidified joint hole and the continuous wall connected to the joint hole may be a cold joint. Even in this case, the water passage path is smaller than when there is no joint hole. The longer, the lower the possibility of water leakage.

In the case where the continuous wall is made to circulate in a box shape, for example, a cold joint is generated as described in claim 2, and the construction start portion of the first constructed continuous wall and the last constructed continuous wall are formed. It is sufficient to form a joint hole at the intersection with the construction end portion, but a joint hole may be formed at the intersection of all continuous walls.

In this case, a joint hole previously filled with a non-consolidating water-impermeable material is formed at both ends of each continuous wall as described in claim 3, and one of the joint holes is formed. The operation of constructing the continuous wall as the starting point up to the other joint hole is repeated, and the ends of the intersecting continuous walls are connected to each other in the joint hole.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS. 1 and 2, the present invention relates to a method for constructing a continuous cross-section of continuous walls 4 of soil cement. A joint hole 5 filled with a liquid containing a non-consolidating water-impermeable material such as bentonite liquid is formed, and the ends of the intersecting continuous walls 4 and 4 are connected to each other in the joint hole 5. , 4 to prevent water leakage.

FIGS. 1 and 2 show a case where the continuous wall 4 is made to circulate in a box shape. However, the continuous wall 4 may be constructed by simply crossing in two directions, or may be newly formed by crossing the existing continuous wall 4. Wall 4
In some cases.

As shown in FIG. 4, the continuous wall 4 circulates the endless chain 2 having the cutting blade 1 around the cutter post 3 while discharging the solidified material liquid into the ground or from the ground.
It is constructed by traversing the cutter post 3 in the ground.

As shown in FIGS. 1 and 2, when the continuous wall 4 is constructed so as to revolve in a box shape, the construction of the continuous wall 4 is started from one end of one side, and the cutter post 3 is attached to the other end. When the cutter post 3 reaches the position, the cutter post 3 is turned, and subsequently the adjacent continuous wall 4 is constructed, so that the joint hole 5 is formed at a position where the cutter post 3 turns. The direction change of the cutter post 3 is performed after the cutter post 3 is once pulled up to the ground or while being inserted into the ground.

The joint hole 5 has a continuous wall 41, 42, 43 which is constructed in advance and a continuous wall 42, 43, 44 which is constructed later and intersects the continuous wall 41, 42, 43 which is constructed in advance. Are formed at any intersection where at least a cold joint may occur.

In the case of FIGS. 1 and 2, the joint hole 5 is formed at the start of the construction of the first continuous wall 41 having the longest time difference and the construction of the last continuous wall 44 at the longest time. It is sufficient to form the joint hole 5 at the intersection with the end portion, but in the drawing, the joint hole 5 is formed at the intersection of all the continuous walls 41, 42, 43, 44.

As shown in FIG. 5A, the joint hole 5 is drilled by a drilling device 6 such as an earth drill while being filled with a liquid containing a non-consolidating water-impermeable material, or as shown in FIG. While containing a non-consolidating water-impermeable material as shown, while discharging a liquid containing a solidifying material such as cement milk,
It is formed by a deep mixing process by a drilling and stirring device 7 having a drilling blade and a stirring blade.

When the solidifying material is added, the joint hole 5 is basically filled with muddy water exhibiting completely liquid properties.
May be filled with viscous, non-fluid mud. In the former case, the joint hole 5 is finally formed as a columnar solidified body by adding and mixing the solidifying material into the muddy water, but the relatively preceding continuous walls 41, 42, 43
If the joint hole 5 does not solidify during the construction at the intersection with the continuous walls 42, 43, 44 to be constructed later, the occurrence of a cold joint is avoided.

At the intersection of the continuous or continuously constructed continuous walls 4, 4, the boundary between the continuous walls 4, 4 intersecting is clearly defined in the joint hole 5 as shown by a broken line in FIG. It doesn't show up. When the mud is filled with the mud, the mud and the solidified material are not mixed, so that the boundaries of the intersecting continuous walls 4, 4 clearly appear as shown in FIG.

In the case where the continuous wall 4 is constructed so as to circulate in a box shape, a non-exposed portion is formed at the intersection of the construction start portion of the first constructed continuous wall 41 and the construction end portion of the continuously constructed continuous wall 44. A joint hole 5 filled only with the solidified water-impermeable material is formed, and a liquid obtained by adding a solidifying material to the non-solidified water-impermeable material is discharged at other continuously constructed intersections. In some cases, the stirring and mixing process may be performed while discharging only the solidifying material.

In each case, the first continuous wall 41 is constructed.
The joint hole 5 at the intersection of the construction start part of the construction and the construction end part of the construction of the continuous wall 44 to be built last
1, 44 are formed with a diameter larger than or equal to the extent that the end face is substantially completely located in the joint hole 5.

The construction of the continuous wall 4 is started by inserting the cutter post 3 into the joint hole 5, discharging a solidifying material liquid such as cement milk, and circulating the endless chain 2 around the cutter post 3.

The joint hole 5 may be formed at that position before the construction of the continuous wall 4 is started, and may be formed at that position before the cutter post 3 reaches the other end. When the joint holes 5 and 5 are formed in advance,
In some cases, the joint hole 5 is formed prior to the construction start position, and the joint hole 5 is formed at the construction end position during construction of the continuous wall 4.

In the case where the continuous wall 4 is constructed so as to revolve in a box shape, a joint hole 5 is formed in advance at the intersection of the adjacent continuous walls 4, 4, and one of the joint holes 5 is used as a starting point. The construction is completed by repeating the operation of constructing the continuous wall 4 up to the other joint hole 5.

FIG. 1 shows that the end faces of the end points of the continuous walls 41, 42, and 43, which are constructed earlier, are the same as those of the continuous walls 42, 43, and 43, which are constructed later. When the construction is performed so as to abut the side of the starting point of 44, FIG. 2 precedes the starting point of the subsequently constructed continuous walls 42, 43 and 44, including the end of the continuously constructed continuous wall 44. This shows a case where the construction is performed so as to overlap the end points of the continuous walls 41, 42, and 43 to be constructed.

In FIG. 1, the construction is performed such that the side face of the end point of the continuous wall 44 constructed lastly comes into contact with the end face of the continuous wall 41 constructed first. 1 and 2, arrows indicate the direction of construction.

FIG. 3 shows the first constructed continuous wall shown in FIG.
The enlarged view of the intersection of both ends of 41 and the continuous walls 42 and 44 adjacent to both sides is shown. Since the solidification of the start point of the first constructed continuous wall 41 is progressing when it is joined to the end point of the last constructed continuous wall 44, it may become a cold joint, but the first The end point portion of the continuous wall 41 and the start point portion of the continuous wall 42 to be constructed subsequently are united in the joint hole 5 by the construction of the continuous wall 42 with discharge and agitation of the solidifying material liquid. Directional wall
No clear boundaries appear at the ends of 41 and 42.

In FIG. 3, even if the intersection between the start point of the first continuous wall 41 and the end point of the last continuous wall 44 is a cold joint, the connecting surface of the continuous continuous walls 41 and 44 intersects completely. 5, the passage of water becomes longer, so that groundwater located outside the joint hole 5 with respect to the building does not enter the inside of the intersection.

[0034]

According to the present invention, a joint hole previously filled with a liquid containing a non-consolidating water-impermeable material is formed at an intersection of a continuous wall constructed in advance and a continuous wall constructed in a later step. By connecting the ends of the continuous walls that intersect in this joint hole, the path of infiltration of groundwater is cut off, thereby preventing water leakage due to the cold joint at the intersection of the soil cement continuous walls that are constructed with a time difference. be able to.

Further, by forming a columnar joint hole having a diameter larger than the width of the continuous wall at the intersection of the preceding continuous wall and the continuous wall to be constructed later, it is assumed that the cylindrical joint hole is temporarily pushed by the pushing force from the cutter post. Even if a crack occurs in the continuous wall, the joint hole surrounds the location where the crack occurs, so that the problem of water leakage due to the crack is solved.

Alternatively, a solidifying material is added to a liquid containing a water-impermeable material to solidify the joint hole, so that a joint hole portion connected to the preceding continuous wall is constructed later. In this case, a sufficient resistance to the pushing force from the cutter post is exerted, so that the occurrence of cracks in the preceding continuous wall is prevented.

In this case, even if the joint between the solidified joint hole and the continuous wall connected to the joint hole becomes a cold joint, the passage path becomes longer than when there is no joint hole, so that the possibility of water leakage is increased. Drops.

[Brief description of the drawings]

FIG. 1 is a plan view showing how a continuous wall orbiting in a box shape is constructed.

FIG. 2 is a plan view showing another construction of a continuous wall orbiting in a box shape.

FIG. 3 is a partially enlarged view of FIG. 1;

FIG. 4 is an elevational view showing how a continuous wall is constructed.

FIGS. 5 (a) and 5 (b) are elevation views showing how a joint hole is formed.

FIG. 6 (a) is a plan view showing groundwater at an intersection of continuous walls according to the present invention, and FIG. 6 (b) is a plan view showing groundwater infiltration at a conventional intersection of continuous walls.

FIG. 7 (a) is a plan view showing a state in which a preceding continuous wall is cracked by the construction of a continuous wall to be constructed later, and FIG. It is the top view which showed the situation when exerting force.

[Explanation of symbols]

1 cutting blade, 2 endless chain, 3 cutter post, 4, 41, 42, 43, 44 continuous wall, 5 joint hole, 6 drilling device, 7 drilling stirring device .

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masaru Tateyama 2-8-3 Hikaricho, Kokubunji-shi, Tokyo Inside the Railway Technical Research Institute (72) Inventor Kosei Fukuda 6-13-7 Akasaka, Minato-ku, Tokyo Tenox Co., Ltd. (72) Inventor Shigeru Yoshida 6-13-7 Akasaka, Minato-ku, Tokyo Tenox Co., Ltd. (72) Inventor Shuji Kami 6-13-7 Akasaka, Minato-ku, Tokyo Tenox U. F Terms (reference) 2D049 EA01 EA02 GA03 GA12 GA15 GA17 GB01 GC11

Claims (3)

[Claims] An endless chain having a cutting blade is circulated around a cutter post, and the cutter post is traversed in the ground while discharging a solidifying material liquid in the ground or from the surface of the ground, thereby forming a continuous wall of soil cement. In the method of building,
The intersection of the continuous wall that is built before and the continuous wall that is built later and intersects the previously built continuous wall is filled with a liquid containing a non-consolidating impermeable material in advance. A method of stopping water at an intersection of soil cement continuous walls in which a joint hole is formed and ends of the intersecting continuous walls are connected to each other in the joint hole. 2. An endless chain having a cutting blade is circulated around a cutter post, and the cutter post is traversed under the ground while discharging a solidifying material liquid in the ground or from the surface of the ground to form a continuous wall of soil cement. In the method of building,
At least the intersection of the continuous wall constructed first and the continuous wall constructed last and intersecting with the first constructed continuous wall was filled with a liquid containing a non-consolidating impermeable material in advance. A method for stopping water at an intersection of a soil cement continuous wall in which a joint hole is formed and ends of the intersecting continuous walls are connected to each other in the joint hole. 3. An endless chain having a cutting blade is circulated around the cutter post, and the cutter post is traversed under the ground while discharging the solidifying material liquid in the ground or from the surface of the ground, thereby forming a continuous wall of the soil cement. In the method of building,
While forming joint holes pre-filled with a liquid containing a non-consolidating water-impermeable material at both ends of each continuous wall, a continuous wall is constructed starting from one of the joint holes to the other joint hole The method of stopping water at the intersection of soil cement continuous walls in which the ends of the continuous walls intersecting are connected to each other in the joint hole.