JP4428833B2 - Construction method of angled underground continuous wall - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an angled underground continuous wall construction method for constructing underground continuous walls that are angled to each other.
[0002]
[Prior art and problems to be solved by the invention]
While circulating an endless chain having a cutting blade around the cutter post, the cutter post is traversed while being inserted into the ground, and at the same time, a solidifying material liquid is discharged from the lower end portion of the cutter post or near the ground surface to obtain a predetermined value. The method of constructing a continuous wall with a wall thickness is limited to the case of constructing a straight continuous underground wall, for example, as disclosed in JP-A-10-159084 and JP-A-11-117349. If the underground continuous wall is attached continuously, it will not work.
[0003]
When building an underground continuous wall with an angle, conventionally, once the entire cutter post is pulled out of the ground at the intersection, the direction of the cutter post is changed, and a new continuous wall is started. It is carried out in the same way that the cutter post is built underground.
[0004]
However, since the entire cutter post is pulled out for each unit that is originally divided as shown in FIG. 7, the following 1) to 7) can be performed by simply pulling out the cutter post on the ground. ), Multiple operations and preparation steps are required, and if a cutter post direction change is included, many operations must be performed.
[0005]
1) While lifting the cutter post for a certain distance, wash the solidified material liquid adhering to the cutter post etc., and hold the raised cutter post with the holder.
[0006]
2) Separate the cutter post with the endless chain attached from the construction machine body at the part on the ground surface, and remove the construction machine body.
[0007]
3) Connect a lifting device with an injection pipe to inject bentonite liquid lifted by a crane to a cutter post with an endless chain that remains in the ground, support the cutter post with a crane, and temporarily remove it from the holder. Separate.
[0008]
4) While injecting the solidified material liquid from the tip of the cutter post and washing the solidified material liquid adhering to the cutter post lifted to the ground, lift the cutter post by a certain distance with a crane and hold it again with the holder.
[0009]
5) Separate the cutter post raised to the ground for each unit. 6) Connect the lifting device with the injection pipe that is lifted again by the crane to the upper part of the cutter post remaining in the ground.
[0010]
7) Repeat the steps from 3) to 6) until the cutter post with the endless chain is collected on the ground.
[0011]
After the direction of the cutter post is changed, the process opposite to the process for pulling out the cutter post is repeated. Therefore, when an underground wall with an angle is constructed, an extremely complicated operation is forced.
[0012]
There are Japanese Patent Laid-Open Nos. 6-1858663 and 9-296478 for changing the direction without pulling the cutter post from the ground, but the former method forcibly pushes the cutter post by turning the entire construction machine. Since the direction is changed, the target ground is limited to ultra-soft ground.
[0013]
The latter is a method in which a number of auger heads that are equipped separately from the cutter post are rotated around the rotation axis to excavate a hole that is bent in the entire direction of rotation, and the cutter post is rotated along this hole. However, it is necessary to equip the construction machine with a large number of auger heads, and it is impossible to construct the cutter post alone.
[0014]
The present invention proposes a method of changing the direction from the above background by using only the cutter post and without pulling out the cutter post from the ground.
[0015]
[Means for Solving the Problems]
In the present invention, among the two-way underground continuous walls constructed at an angle to each other, the underground continuous that precedes the intersection of the underground continuous wall constructed in advance and the underground continuous wall intersecting with the underground continuous wall. A widening wall with a wall thickness larger than the wall thickness is constructed by discharging the solidified liquid , and the cutter post can be redirected within the widening wall before it is solidified , and the cutter post is pulled out from the ground. Without any problem, the underground continuous wall in a different direction from the preceding underground continuous wall is continuously constructed .
[0016]
The preceding underground continuous wall allows the endless chain with cutting blades to circulate around the cutter post while traversing while the cutter post is inserted into the ground, and at the same time, solidifying material from the lower end of the cutter post or near the ground surface It is constructed by discharging the liquid, and a widening wall having a wall thickness 1.3 to 1.5 times the wall thickness is constructed by discharging the solidifying material liquid continuously to the underground continuous wall.
[0017]
Preceding underground continuous wall wall thickness greater than the wall thickness of the widening walls of the reciprocating in the construction position of the widened wall cutter post in the case of construction while wearing endless chain was constructed underground continuous wall the preceding Although the construction by, after construction of the diaphragm wall the preceding as described in claim 2, a portion of the cutting edge of the endless chain once to replace the large cutting edge in the width direction end distance construction If so, the widening wall can be constructed without necessarily reciprocating the cutter post.
[0018]
If the widening wall does not solidify until the direction change of the cutter post is completed, the construction of the widening wall and the construction of the continuous continuous underground wall will continue from the end of the construction of the preceding underground continuous wall. However, from the viewpoint of easy direction change of the cutter post inside the widened wall, when the widened wall is not solidified, the bentonite liquid or the low concentration which does not solidify the widened wall as described in claim 3. The widening wall is constructed while supplying the solidifying material liquid into the ground.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 6, the underground continuous wall 4 circulates an endless chain 2 having a cutting blade 1 around the cutter post 3, and at the same time traverses while the cutter post 3 is inserted into the ground, It is constructed by discharging a solidified liquid such as cement milk having a predetermined concentration from the lower end or near the ground surface, and has a wall thickness larger than the wall thickness continuously from the underground continuous wall 4 as shown in FIG. The widening wall 5 is constructed .
[0020]
FIG. 1- (a) shows a state in which the cutter post 3 reaches the end of the underground continuous wall 4. The construction of the widening wall 5 is made by moving the cutter post 3 from the state (a) until the cutting blade 1 located on the rear side in the traveling direction of the cutter post 3 reaches the end of the underground continuous wall 4 (b). Start from state.
[0021]
In the state shown in FIG. 1- (b), the cutting blade 1 shown in FIG. 3- (a) is temporarily placed between both ends in the width direction as shown in FIG. 3- (b) or (c). Replace the cutting blade 6 with a longer distance, and switch the solidifying material liquid to a water-soluble liquid mixed with clay such as bentonite or a low concentration solidifying material liquid that does not solidify the widening wall . The solidified material concentration on the widening wall 5 side is lowered from the boundary between the underground continuous wall 4 and the widening wall 5 shown in FIG.
[0022]
The widening wall 5 may be constructed while continuing to discharge the solidifying material liquid from the time of construction of the underground continuous wall 4 without switching the discharge of the solidifying material liquid to bentonite liquid or the like.
[0023]
In FIG. 1, when the cutting blade 1 located on the front side in the advancing direction of the cutter post 3 reaches the end of the underground continuous wall 4, the cutting blade 1 is replaced with the cutting blade 6, and the solidified material liquid is discharged by bentonite liquid. However, the cutting blade 1 may be replaced and the discharge liquid may be switched while the cutter post 3 is further advanced to the position (d).
[0024]
The cutting blade 6 for the construction of the widening wall 5 is a plate 1a on which a cutting blade 1 for construction of the underground continuous wall 4 shown in FIG. The plates 6a and 6b project from the wider plate, and the cutting blade 1 and the cutting blade 6 are exchanged for each of the plates 1a and 6a (6b). FIG. 3 (c) shows a case where the width of the plate 6b is larger than the plate 6a shown in FIG. 3 (b). In the case of (c), the distance between both ends in the width direction of the cutting blade 6 is larger than in the case of (b). .
[0025]
The replacement from the cutting blade 1 to the cutting blade 6 is performed on the cutting blade 1 of the endless chain 2 that is on the ground in FIG. 6, and after the replacement, the endless chain 2 is circulated while the endless chain 2 is circulated. As shown in 1- (d), the widening wall 5 is constructed by traversing the cutter post 3 forward in the traveling direction.
[0026]
When the endless chain 2 cannot be continuously circulated because the distance between both ends in the width direction of the cutting blade 6 is large, the cutting blade 6 located at the head in the direction in which the endless chain 2 circulates is the deepest part in the ground. The remaining cutting blade 1 on the ground is replaced with the cutting blade 6, and the endless chain 2 is circulated in the reverse direction.
[0027]
Circulation in the reverse direction of the endless chain 2 is performed until the cutting blade 6 that is located at the head during the circulation in that direction reaches the deepest part in the ground. The fact that the cutting blade 6 replaced later has reached the deepest part in the ground is confirmed by the fact that the cutting blade 6 replaced first appears on the ground.
[0028]
Thereafter, the widening wall 5 is constructed by traversing the cutter post 3 while circulating the endless chain 2 in the original circulation direction. When the discharge of the solidifying material liquid is switched to bentonite liquid or the like at the time of FIG. 1- (b), the widened wall 5 in which bentonite liquid or the like and earth and sand are mixed is constructed .
[0029]
Since the wall thickness of the widening wall 5 is determined by the distance between both ends in the width direction of the cutting blade 6 exchanged in FIG. 1- (c), the cutting blade 6 shown in FIG. As the cutting blade 6 having a larger distance between both ends shown is used, the widened wall 5 having a larger wall thickness can be constructed , and the rotation angle of the cutter post 3 can be secured at the time of changing the direction of the cutter post 3. angle between underground continuous wall 4 was constructed to underground continuous wall 7 and above are the construction Te can be increased.
[0030]
In addition, when constructing the widening wall 5 having a wall thickness larger than the wall thickness of the underground continuous wall 4, both ends in the width direction of the cutting blade 1 shown in FIG. The cutting blade 1 is replaced with the cutting blade 6 so that the difference between the distance and the distance between both ends in the width direction of the cutting blade 6 shown in FIG. 3- (b) or (c) does not become extremely large.
[0031]
For example, when the plate 1a with the cutting blade 1 shown in FIG. 3- (a) is suddenly replaced with the plate 6b with the cutting blade 6 shown in FIG. 3- (c), the plates 1a and 6b are positioned on both sides in the width direction. Since the distance between the cutting blade 1 and the cutting blade 6 is large, a portion between the cutting blade 1 and the cutting blade 6 may be left without being excavated.
[0032]
In the case where there is a possibility that an unexcavated portion may be generated as described above, when the plate 1a with the cutting blade 1 shown in FIG. 3 (a) is replaced with the plate 6b with the cutting blade 6 shown in (c), Once the plate 1a in FIG. 3- (a) is replaced with the plate 6a in (b) and the widening wall 5 having a wall thickness corresponding to the distance between both ends of the cutting blade 6 is constructed , The plate 6a is replaced with the plate 6b of (c), and the widening wall 5 having a wall thickness corresponding to the distance between both ends of the cutting blade 6 in the width direction is applied .
[0033]
At the time of drawing construction widening wall 5 is completed 1-(d), the diaphragm wall 7 for construction crossing the cutting blade 6 which was constructed a widened wall 5 (e), the Figure 3- ( The original cutting blade 1 shown in a) is replaced.
[0034]
When the discharge of the solidifying material liquid is switched to bentonite liquid or the like at the time of FIG. 1- (b), a cutter is used to solidify the widening wall 5 and ensure continuity with the preceding underground continuous wall 4. While the post 3 is traversed and the endless chain 2 is circulated, the solidifying material liquid is discharged from the lower end portion of the cutter post 3 and the solidifying material liquid is stirred and mixed in the widening wall 5. Is returned to the construction start position of the widening wall 5 as shown in (f).
[0035]
Alternatively, the bentonite liquid or the like is switched to the solidified material liquid when the cutter post 3 returns to the construction start position of the widening wall 5 shown in (f). In this case, the cutting blade 6 may be replaced with the cutting blade 1 when the cutter post 3 is returned to the construction start position of the widening wall 5.
[0036]
When switching from bentonite liquid or the like to the solidified material liquid at the position shown in FIG. 1- (f), the endless chain 2 is circulated while discharging the solidified liquid to the position shown by the two-dot chain line in FIG. if it caused to traverse the cutter post 3 Te, since the solidifying material liquid in the widening walls 5 are stirred and mixed, widening wall 5 is construction as a continuous wall having an intensity equivalent to the underground continuous wall 4 was constructed previously The continuity and integrity of the underground continuous wall 4 and the widened wall 5 can be ensured.
[0037]
The direction of the cutter post 3 is changed at any position within the widening wall 5 indicated by a two-dot chain line in FIG. The direction change of the cutter post 3 is performed, for example, by changing the direction of the caterpillar of the construction apparatus shown in FIG.
[0038]
If the position changing directions of the cutter post 3 have collided cutting blade 1 after turning within the hole wall of the widening wall 5 may be a one position within the widened walls 5, underground continuous pre construction It is also performed near the wall 4 or the other side.
[0039]
After changing the direction of the cutter post 3, as in the construction of the preceding underground continuous wall 4 as shown in FIG. 2- (b), the cutter post 3 while circulating the endless chain 2 accompanied by the discharge of the solidified liquid. is rampant starts, construction of underground continuous walls 7 which intersect in the same manner as the construction of the underground continuous wall 4 preceding as shown in FIG. 2-(c) is carried out.
[0040]
Since the stirring and mixing of the solidified material liquid is performed in the widening wall 5, by performing as it construction of underground continuous walls 7 after turning the cutter post 3, diaphragm wall 7 and widening wall 5 crossing Is also ensured.
[0041]
4 shows a case where a widened wall 5 having a wall thickness of about 1.5 times the wall thickness of the preceding underground continuous wall 4 is constructed , and FIG. 5 shows that a widened wall 5 having a wall thickness of about 1.3 times is constructed. However, the angle at which the center lines of the former ground walls 4 and 7 intersect is about 1.7 times the angle at which the center lines of the latter ground walls 4 and 7 intersect. The larger the wall thickness, the larger the angle at which the underground walls 4 and 7 intersect.
[0042]
【The invention's effect】
Among the two-way underground continuous walls constructed at an angle to each other, the walls of the underground continuous wall that precedes the intersection of the underground continuous wall that is constructed in advance and the underground continuous wall that intersects it. Since a widened wall with a wall thickness greater than the thickness is constructed, it is possible to change the direction of the cutter post within the widened wall, and by using only the cutter post, the preceding underground continuation without being pulled out from the ground Underground continuous walls with different directions from the walls can be constructed continuously.
[0043]
In claim 2, after the construction of the preceding underground continuous wall, a part of the cutting blade of the endless chain is once replaced with a cutting blade having a large distance between both ends in the width direction, so that the cutter post is reciprocated within the widening wall. A widening wall can be constructed without moving it.
[0044]
In claim 3, since the widening wall is not solidified by constructing the widening wall while supplying bentonite liquid or a low-concentration solidifying material liquid into the ground, it is easy to change the direction of the cutter post inside the widening wall. Can do.
[Brief description of the drawings]
FIGS. 1A to 1F are plan views showing a construction procedure of a preceding underground continuous wall and a widened wall.
FIGS. 2A to 2C are plan views showing a construction procedure of an underground continuous wall intersecting with a widened wall.
3A is a plan view showing a cutting blade for building an underground continuous wall, and FIGS. 3B and 3C are plan views showing a cutting blade for building a widened wall. FIG.
FIG. 4 is a plan view showing a construction example of a widening wall in the case of constructing an underground continuous wall having a large intersecting angle.
FIG. 5 is a plan view showing an example of construction of a widened wall in the case of constructing underground continuous walls with a small intersecting angle.
FIG. 6 is an elevation view showing a cutter post and a construction machine.
FIG. 7 is an elevational view showing a connected state of units constituting the cutter post.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Cutting blade, 1a ... Plate, 2 ... Endless chain, 3 ... Cutter post, 4 ... Underground continuous wall, 5 ... Widening wall, 6 ... Cutting blade, 6a ... Plate, 7 ... ... underground continuous wall.

Claims (3)

It is a construction device limited to constructing a straight underground wall, and while circulating an endless chain having a cutting blade around the cutter post, the cutter post is traversed while being inserted into the ground, The solidified material liquid is discharged from the lower end of the cutter post or near the ground surface to construct an underground continuous wall with a predetermined wall thickness, and the wall thickness is 1.3 to 1. After expanding the widening wall with a wall thickness of 5 times by discharging the solidified material liquid , the cutter post is turned in the widened wall before the widened wall is solidified, and the endless chain is circulated while discharging the solidified material liquid. The construction method of the underground continuous wall with an angle which constructs the underground continuous wall of a predetermined wall thickness by constructing the underground continuous wall with a predetermined wall thickness by moving the cutter post while being inserted into the ground. The angled underground continuous wall according to claim 1, wherein after the preceding underground continuous wall is constructed, the widened wall is constructed by replacing a part of the cutting blade of the endless chain with a cutting blade having a large distance between both ends in the width direction. How to build. The construction method of the angled underground continuous wall of Claim 1 or Claim 2 which constructs a widened wall, supplying a bentonite liquid or the low concentration solidification material liquid which does not solidify a widened wall in the ground.

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