JPH01310011A - Underground continuous wall construction - Google Patents

Abstract

PURPOSE:To construct an underground wall without moving an obstruction by forming a leading groove with a normal excavator to the adjoining part and the directly upper part of an underground obstruction, then excavating the directly lower part of the obstruction and widening width with a horizontal excavator, and inserting the reinforced cage having a recessed part to be concreted. CONSTITUTION:When an obstruction is in an underground, a leading groove 3 is excavated and formed by excavating the adjoining part and the upper part of the obstruction 1 with an excavator. Next the groove 3 width is widened by excavating the directly lower part of the obstruction 1 with a horizontal excavator 6 lowered in the groove 3. Then a reinforced cage having the recessed part corresponding to the underground obstruction is hung down in the width- widened groove 3 to laterally moved, and the obstruction is taken in the recessed part. Finally an underground continuous wall is provided by concreting with a tremie tube etc. This enables the underground continuous wall to be provided without moving or removing the underground obstruction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an underground continuous wall construction method when there are obstacles such as underground objects or surface structures.

[Conventional technology]

If there are obstacles such as underground structures such as water distribution pipes or power distribution pipes or surface structures in the area where the underground continuous wall is to be constructed, the underground continuous wall should be constructed after the obstacles are relocated and removed. I will do it.

On the other hand, in order to relocate and remove the obstacles at the same time as the continuous wall construction, auxiliary construction methods such as chemical injection, SMW (cement milk continuous wall using multi-axis auger), and continuous wall construction using column jets can be used to remove the obstacles. Reinforce the back of the continuous wall construction area where there is a wall, and then remove this obstacle and build a continuous wall.

This construction will be carried out using the reverse winding method as the excavation progresses.

[Problem to be solved by the invention]

If the removal of obstacles is to be carried out prior to the construction of the underground wall, excavation and other work must be carried out separately from the underground wall construction, and the removal work must be carried out at the same time. Even in some cases, auxiliary construction methods were required, which was extremely troublesome and time-consuming.

An object of the present invention is to eliminate the disadvantages of the conventional example and to provide an underground continuous wall construction method that can take in obstacles and construct a continuous wall directly below them without removing and relocating them.

[Means to solve the problem]

In order to achieve the above object, the present invention excavates the area adjacent to and just above the obstacle using a commonly used excavator to form a leading trench, and then lowers the horizontal excavator into the leading trench to directly beneath the obstacle. horizontally excavate and widen the trench, suspend a reinforcing bar cage with a recess formed on the side in the leading trench, move it laterally to take the obstacle into the recess, or remove the upper part of the obstacle and the adjacent part. A reinforcing bar cage with an enlarged upper diameter that is arranged in the upper part, and a reinforcing bar cage that is combined with a reinforcing bar cage for pulling out inside is suspended in the preceding groove, and the reinforcing bar cage for pulling out is pulled out directly below the obstacle. The purpose of this project is to remove obstacles from the ground and place concrete.

[Function] According to the present invention, even if there are obstacles such as underground objects or surface structures at the location where the underground continuous wall is to be constructed, the construction can be carried out without having to relocate or remove them, and the construction can be streamlined. can.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

1 to 7 are side views showing each step of the first embodiment of the underground continuous wall construction method of the present invention, and 1 in the figures indicates obstacles such as underground objects and surface structures.

As shown in Figure 1, the area adjacent to and directly above the obstacle 1 is excavated using a commonly used excavator 2 such as a excavation packet such as a clamshell, an earth drill, or an earth auger, or a rotary excavator. A leading groove 3 is formed on the side of the object 1.

This leading groove 3 has a certain width and is of the same depth as that required for the continuous wall to be constructed. In the figure, 4 indicates a stabilizing liquid that prevents pore wall collapse.

Next, as shown in FIG. 2, a guide 5 made of H-shaped steel or the like is erected in the leading groove 3 to also serve as a reaction wall, and a horizontal auger 6 as a horizontal excavator is attached to the guide 5 so as to be movable up and down. This horizontal excavator excavates directly below the obstacle 1 in the horizontal direction.

As shown in FIGS. 8 to 10, the horizontal auger 6 includes a telescoping device 7 attached to the guide 5 and having a telescoping arm 7a using a hydraulic jack or the like, a drive device 8 using an electric motor or a hydraulic motor, and this drive device. The auger screw 9 is provided with a casing 10 around it, and its tip is formed as a rectangular cutting edge 11 with a cutter bit.
The auger head 9a provided at the tip of the blade is positioned within or in front of the blade mouth 11. In the figure, reference numeral 12 indicates an earth and sand intake port formed in the auger head 9a, and reference numeral 13 indicates an adjustable guide for posture control provided outside the casing 10.

If the drive device 8 rotates the auger screw 9 and the auger head 9a and simultaneously extends the telescopic arm 7a, the earth and sand excavated by the auger throat 9a and the cutting edge 11 will flow from the earth and sand intake port 12 to the auger screw. It is transported backward by the screw blade 9 and falls from the rear of the drive device 8 to the bottom of the leading groove 3.

In this way, the area directly below the obstacle 1 is excavated horizontally, and once one stage of horizontal excavation has been completed, the telescopic arm 7a is retracted, the horizontal auger 6 is lowered along the guide 5, and the area immediately below it is excavated horizontally again. Widen the leading groove 3 (see Figure 3).

During or after excavation, the excavated soil deposited at the bottom of the preceding trench 3 is discharged to the ground through the earth discharge pipe 14 using a fluid transport method using an air lift or pump, or directly discharged in a packet or the like.

As shown in FIG. 4, a reinforcing bar cage 16 with a recess 15 formed in advance on its side surface is suspended in the leading groove 3, and the reinforcing bar cage 16 is laterally moved to take the obstacle 1 into the recess 15.

As shown in FIG. 5, the reinforcing bar cage 16 can be moved horizontally by suspending the upper end hanging portion 16a with a lifting machine such as a crane, or by horizontally moving the reinforcing bar cage 16 or the ground. 17 may be attached and extruded using this, or both may be used together.

Once the reinforcing bar cage 16 is set as described above, concrete 19 is placed using the tremie pipe 18 as shown in FIG. 6, and the underground continuous wall 20 is completed as shown in FIG. 7.

In addition, if the width of the continuous underground wall 20 to be constructed is large and occupies this part of the interior of the preceding groove 3 after horizontally moving the reinforcing bar cage 16, it should be placed parallel to the reinforcing bar cage 16 and separate from the wall (not shown). A large width reinforcing bar cage is constructed by suspending and setting reinforcing bar cages.

In addition, if the width of the continuous wall is excessive in the preceding groove 3, a partition plate 21 made of a steel plate or the like is attached to the side of the reinforcing bar cage 16 so that the poured concrete 19 flows out toward the preceding groove 3. After constructing the underground continuous wall 20, earth and sand should be buried in the preceding trench 3.

11 to 13 show the other side of the horizontal excavator which is attached to the guide 5 so as to be movable up and down.

The details of the device shown in FIG. 11 are shown in FIG. 14, and a holding arm 23 is provided in a tiltable manner on a chain drive device 22 using an electric motor or a hydraulic motor that moves the guide up and down. Sprocket 24.
A chainsaw or chain packet 25 is wound around 24'. One of the sprockets 24, 24' is a drive sprocket connected to the chain drive 22.

Although not shown, a telescoping device 7 having a telescoping arm 7a using a jack or the like as shown in FIG. 8 may be interposed between the chain drive device 22 and the guide 5.

To horizontally excavate directly below the obstacle 1, attach the holding arm 23 vertically to a predetermined position on the guide 5 as shown by the chain line in FIG. Excavation is performed by slowly rotating the holding arm 23 while

When the holding arm 23 becomes horizontal, excavation is carried out by moving the entire chain saw or chain packet 25 up and down along the guide 5 while rotating only the chain saw or the chain packet 25.

The details of the device shown in FIG. 12 are shown in FIG. 15, and a bendable telescoping arm 27 with a hydraulic cylinder attached is provided on a holder 26 that moves the guide 5 up and down.
A packet 28 such as a backhoe was rotatably attached to the end. In the figure, 29 indicates the expansion and contraction of the arm 27 and the packet 28.
The hydraulic hose that controls the rotation of the is shown.

In order to excavate directly below the obstacle 1, the guide 5 is attached to a predetermined position in the middle, and the packet 28 is excavated while extending the telescopic arm 27.

When the excavation within the turning range of the packet 28 is completed, the whole is moved up and down along the guide 5 and excavation is performed sequentially in the same manner.

As shown in FIG. 13 in detail, an auger drive device 30 consisting of an electric motor and a hydraulic motor that moves the guide 5 up and down is provided with an auger screw 31 that is tiltable. An auger head 32 is formed with a cutter 32a implanted at the tip of the auger head 31.

As shown by the chain line in FIG. 13, the auger screw 31 is installed in a predetermined position on the guide 5 in a vertical state, and the auger screw 31 and the auger head 3 are driven by the drive device 30.
Excavate by slowly rotating the whole body while rotating 2.

When the auger screw 31 becomes horizontal, the entire auger screw 31 is moved up and down while keeping it in the same state to perform excavation.

In this case as well, a telescoping device 7 having a telescoping arm 7a may be interposed between the auger drive device 30 and the guide 5.

17 and 18 are side views showing a second embodiment of the present invention, in which the reinforcing bar cage 33 uses a stepped reinforcing bar cage with an enlarged upper diameter to be placed above and adjacent to the obstacle 1. This is the case.

This reinforcing bar cage 33 has a built-in reinforcing bar cage 33a for pulling out in its lower part, and a rope 34 for pulling out the cage is attached to this reinforcing bar cage 33a for pulling out via guide rollers 35.

Alternatively, a jack 36 for pushing out the basket may be attached in place of or together with the rope 34 for pulling out the basket.

The reinforcing bar nW33 is suspended into the leading groove 3 with the reinforcing bar ff[33a housed therein, and then the reinforcing bar dragon 33a is suspended by pulling the rope 34 from the ground and extending the jack 36.
Pull out the reinforcement and place it in the empty space directly under Obstacle 1.

If concrete is poured after doing this, the obstacle 1 is incorporated into the reinforcing bar 33, and an underground continuous wall with a large width including the leading trench 3 is obtained.

In addition, if the construction method of the present invention using the retractable reinforcing bar cage 33 as shown in FIGS. 17 and 18 is applied, the wall thickness of the continuous wall can be increased arbitrarily even when there is no obstacle 1. As shown in Figs. 19 and 20, underground continuous walls 20 and continuous wall foundations 3 that have a wider wall thickness than the wall thickness a.
7 can be created. Further, it is possible to increase the supporting force immediately below the enlarged diameter portion of the widened wall thickness.

〔Effect of the invention〕

As described above, the underground continuous wall construction method of the present invention can construct a continuous wall by incorporating underground objects or surface structures without having to relocate or remove them, which is conventionally done for relocation and removal. By omitting the previously mentioned process, construction can be streamlined and costs can be reduced.

[Brief Description of the Drawings] Figures 1 to 7 are side views showing each step of one embodiment of the underground wall construction method of the present invention, and Figure 8 is a partially cutaway side view showing details of the horizontal auger. Figure 9 is a view taken along arrow A-A in Figure 8;
Figure 10 is a sectional view taken along the line B-B in Figure 9, and Figures 11 to 13.
The figure is a side view showing the other side of the horizontal excavator, and Figure 14 is a side view showing the other side of the horizontal excavator.
FIG. 15 is a side view showing details of the excavator shown in FIG. 12, FIG. 16 is a side view showing details of the excavator shown in FIG. Figure 18 is a side view of the process showing the second embodiment of the construction method of the present invention, Figures 19 and 20
The figure is a longitudinal cross-sectional side view of an underground continuous wall created by applying the construction method of the present invention. 1... Obstacle 2... Ordinarily used excavator 3... Leading groove 4... Stabilizing liquid 5... Guide 6... Horizontal auger 7... Telescopic device 7a... Telescopic Arm 8...drive device
9... Auger screw 9a... Auger head 10... Casing 11... Rectangular cutting edge
12... Sediment intake port 13... Adjustable guide 14... Earth discharge pipe 15... Recessed portion 16...
・Reinforcing bar t[16a... Hanging part 17... Horizontal jack 18... Tremy pipe 19... Concrete 20... Underground continuous wall 21... Partition plate 22.
... Chain drive device 23 ... Holding arm 24.2
4'...Sprocket

Claims (2)

[Claims] (1) Excavate the area adjacent to and directly above the obstacle with a commonly used excavator to form a leading trench, lower the horizontal excavator into the leading trench, and use it to horizontally excavate directly below the obstacle. An underground continuous wall characterized by suspending a reinforcing bar cage that has been widened and has a recess formed on the side surface in a leading groove, moving the cage laterally to take an obstacle into the recess, and pouring concrete. Construction method. (2) Use a commonly used excavator to excavate the area adjacent to and directly above the obstacle to form a leading trench, lower the horizontal excavator into the leading trench, and use it to horizontally excavate directly below the obstacle. A reinforcing bar cage with an enlarged upper diameter that is widened and placed above and adjacent to the obstacle, and a reinforcing bar cage that is combined with a reinforcing bar cage for pulling out inside is suspended in the preceding groove and placed directly below the obstacle. This underground continuous wall construction method is characterized by pulling out a rebar cage, trapping obstacles inside the rebar cage, and pouring concrete.