JPH06108459A - Construction of underground continuous wall - Google Patents

Abstract

PURPOSE:To construct a highly rigid, satisfactorily watertight underground continuous wall in simple process without using reinforcing bar baskets. CONSTITUTION:A steel casing 2, made up of a barrel-like plate body that is equipped with restraint reinforcing materials 4 projecting toward its inside and is further equipped on both sides thereof with joints 6 and 6' for engaging with each other, is installed on the ground. The bottom of the ground is excavated to some extent with an excavator 7 that is brought into the inside of the casing, and the casing is driven into earth with a placement machine 12. After the casing is settled into a specified depth by repeating the above-mentioned processings, the inside of the casing is filled with concrete 3. Adjoining new steel casings 2 and 2 are installed to the right and the left of the settled steel casing 2, and the new steel casings 2 are driven in for settlement, being connected with the steel casing in the middle with the joints 6 and 6' engaged with each other. Then, works for placing concrete 3 to the inside are repeated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing an underground continuous wall.

[0002]

2. Description of the Related Art A conventional underground continuous wall is an underground continuous wall for a temporary earth retaining wall made of reinforced concrete made of normal underwater concrete, or a connecting rebar embedded in a rebar cage to connect floors, columns and walls. There are underground continuous walls that are placed and used as the main structure or part of the main structure as it is, both of which excavate the element by a mud excavation method using a bucket type or a screw auger, and inside it, a rebar cage or After the steel frame rebar cage was sunk, the method of filling concrete was used.

[0003]

SUMMARY OF THE INVENTION In the above conventional method,
Securing the position of the connecting rebars to be connected to the floor, pillars, and walls that are embedded in the rebar cage in advance, setting the height of continuous rebar cages to a predetermined position, and when placing concrete, Preventing uplift is almost impossible, and preventing collapse of the element wall surface during excavation was a difficult task even with the utmost care depending on the soil quality.

[0004]

SUMMARY OF THE INVENTION The present invention is a steel plate made of a cylindrical plate having a restraining reinforcing member 4 projecting from the inner surface thereof and joint pieces 6 and 6'interlocking with each other on both side surfaces provided vertically. Excavator 7 with casing 2 installed on the ground and placed inside
After excavating the bottom ground to some extent by repeating the steps of driving into the ground by the driving machine 12, the concrete is filled into the inside after being sunk to a predetermined depth, and then the steel casing 2 is adjacent to the left and right. The steel casings 2 and 2 are newly installed at the positions, and the new steel casing 2 is laid down in the same manner as described above while the joint pieces 6 and 6 ′ of the steel casings 2 and 2 adjacent to each other are engaged and connected. It proposes a construction method for a continuous underground wall in which the step of placing concrete 3 inside is repeated.

[0005]

[Operation] Steel casing 2 and concrete 3 inside
Can be integrated with the restraint reinforcement material 4 to obtain the underground continuous wall 1 with high rigidity, and the construction can be done quickly without the need for a rebar cage.
The excavated surface can be easily held by the steel casing 2.

[0006]

EXAMPLE A continuous underground wall 1 of the present invention is constructed by immersing a steel casing 2 made of a tubular plate body in the ground and filling concrete 3 therein.

As shown in FIGS. 1 to 4, the steel casing 2 is a hollow box type for the straight wall portion of the underground continuous wall 1 and a hollow hook type for the corner portions of the wall. For the inflection part, a steel plate such as a hollow S-shape or a hollow lightning bolt is used to form a transverse cross section suitable for the installation part, and the inner surface of the concrete 3 is integrated with the concrete 3 filled to the required strength. A large number of restraint reinforcements 4 such as jibbels for holding are attached at predetermined intervals in the vertical and horizontal directions, and for reinforcing the tip of the driven bottom against the hard ground or the like on one or both of the inner and outer surfaces of the lower end. The reinforcing plate 5 is attached.

The restraint reinforcement member 4 has its mounting position set so as to be used also as a guide for an excavator described later.

On both sides of the steel casing 2, joint pieces 6, 6'having a hook-shaped cross section for firmly fitting and connecting the horizontally adjacent steel casings 2, 2 are connected in the vertical direction. One or more are attached in series.

FIG. 5 shows the connected state of the steel casing 2 having two joint pieces 6 and 6'mounted on both side surfaces. In this case, two sets are provided between the adjacent steel casings 2 and 2. Since it is partitioned by the joint pieces 6, 6'of
The water stopping property is improved as compared with the case of.

When constructing the underground continuous wall 1 using the steel casing 2 having the above structure, first, the steel casing 2 is installed at a predetermined position as shown in FIG. The excavator 7 is put in to excavate the bottom sediment.

As the excavator 7, in the embodiment shown in FIGS. 1 and 3, a hydraulic excavator for excavating by injecting water pressure-fed from the water pipe 8 as jet water is shown.
It is possible to use various excavators such as a jet-excavator equipped with an auger at its tip, or an excavator provided with a grab bucket at the tip of a boom.

The water pipe 8 of the excavator 7 is attached together with the sludge discharge pipe 9 to a lift table 11 provided with rollers 10 on the periphery thereof, and a steel casing is provided while guiding the lift table 11 by the restraining reinforcement members 4 arranged vertically. After lowering the inside of 2, and excavating the excavated earth and sand excavated by the excavator 7 by the mud pipe 9, the bottom ground is excavated to the required depth, and then the steel casing 2 is driven by the driving machine 12 by hydraulic pressure or vibration, and sequentially. The same process is repeated to submerge the steel casing 2 in the ground.

If the vertical length of the steel casing 2 is smaller than the depth of the underground continuous wall 1 to be constructed, the steel casing 2 shown in FIG.
As shown in (1), a plurality of layers are sequentially stacked on top of each other, and their joint ends are welded to be connected and integrated.

After the steel casing 2 is sunk in this way, the bottom slime is removed as shown in FIG. To finish.

Next, the steel casing 2 is newly installed at a position adjacent to the left and right of the steel casing 2 of the underground continuous wall 1 constructed as described above, and the adjacent joint pieces 6 and 6'are engaged with each other. A new steel casing 2 is sunk in the same manner as described above while being connected, and concrete 3 is placed therein.

As a procedure of the above construction, for example, as shown in FIG.
After the individual excavation and installation, the adjacent second steel casings 2 on both sides are excavated and installed, and then the second steel casing 2 (third numerical order) is overlaid on the first steel casing 2. Next, a method of constructing a fourth steel casing 2 adjacent to the second steel casing 2 and successively arranging them vertically and horizontally in accordance with the installation order of FIG. 6 is adopted.

The constructed underground continuous wall 1 can be used as an earth retaining wall as it is, like the conventional underground continuous wall, or can be supported by the belly up 13 and the girder 14 as shown in FIG. 10, FIG. 11 or FIG. However, after excavating the inside of the underground continuous wall 1, the floor member 15 and the beam member 16 can be directly welded to the steel casing 2 to use the underground continuous wall 1 as a peripheral wall member of an underground permanent structure.

[0019]

As described above, according to the present invention, it is possible to obtain an underground continuous wall having a high rigidity and a high water-tightness, in which the steel casing and the concrete inside are integrated.
Since there is no need for a rebar cage as in the past, construction management is simple and construction can be done smoothly and quickly. Further, since the steel casing is sunk while excavating the bottom ground, it becomes easy to hold the excavated surface against the collapse of the earth and sand.

When the underground continuous wall is used for the main body of the structure, the installation of the intermediate beam / floor joint rebar and steel frame will be done afterwards, so there is no difficulty like installing a conventional rebar cage, Can be installed accurately.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing a sinking state of a steel casing according to the present invention.

FIG. 2 is a vertical sectional side view of a steel casing according to the present invention.

FIG. 3 is a plan view showing an installed state of a steel casing according to the present invention.

FIG. 4 is a front view of a steel casing according to the present invention.

FIG. 5 is a plan view showing an installed state of a steel casing according to another aspect of the present invention.

FIG. 6 is a process outline view showing an example of a construction sequence of an underground continuous wall of the present invention.

FIG. 7 is a vertical cross-sectional side view showing the step of sinking the steel casing according to the present invention.

FIG. 8 is a vertical cross-sectional side view showing a state in which steel casings according to the present invention are vertically stacked.

FIG. 9 is a vertical cross-sectional side view showing a state in which concrete is placed in a steel casing according to the present invention.

FIG. 10 is a vertical sectional side view showing a construction state when the underground continuous wall constructed according to the present invention is used for a main body structure.

FIG. 11 is a vertical cross-sectional side view showing one embodiment in the case where the underground continuous wall constructed according to the present invention is used for a main body structure.

FIG. 12 is a vertical cross-sectional side view showing another embodiment of the case where the underground continuous wall constructed according to the present invention is used for the main body structure.

[Explanation of symbols]

 1 Underground continuous wall 2 Steel casing 3 Concrete 4 Restraint reinforcing material 5 Reinforcement plate 6 Joint piece 6'Joint piece 7 Excavator 8 Water pipe 9 Mud pipe 10 Roller 11 Lifting table 12 Laying machine 13 Raising 14 Cut beam 15 Floor member 16 Beam member

Claims (1)

[Claims] 1. A steel casing made of a tubular plate body having a constraining reinforcing material protruding from the inner surface thereof and having joint pieces engaging with each other on the both sides provided in the up-and-down direction is installed on the ground, and the steel casing is put in the interior of the steel casing. After excavating the bottom ground a little with an excavator and driving it into the ground with a placing machine, it is sunk to a predetermined depth and then filled with concrete, then adjacent to the left and right of the steel casing A new steel casing is installed at the position, the new steel casing is sunk in the same manner as described above while the joint pieces of adjacent steel casings are engaged and connected, and concrete is placed inside the casing. Construction method of underground continuous wall characterized by repeating.