JPH02171413A - Method for constructing underground continuous wall - Google Patents

Abstract

PURPOSE:To improve strength by falling a cleaning device into a deep groove provided at one side of an underground wall to clean the neighborhood of the one side and also removing remains formed on the inner wall between both the adjacent deep grooves by the cutter of the cleaning device. CONSTITUTION:A secondary deep groove H2 is drilled at the side of an underground wall W1 constructed previously to form remains T at the continuous portion between both the deep grooves H1, H2. A cleaning device 5 is fallen along a guide rail 6 with ejecting cleaning liquid from get nozzles 10 and the remains T are cut down in turn by a cutter 12. Next, slime and sediment cut down are removed with the cleaning liquid and also they are scraped off with a brush 13 to be fallen on the bottom of the deep groove H2.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for constructing an underground continuous wall, particularly for a subway, an underground mall, an underground parking lot, or a water-stop wall for an underground LPG storage tank. The present invention relates to a method of constructing an underground continuous wall suitable for use in underground structures.

[Prior Art] Conventionally, when constructing an underground continuous wall such as a cutoff wall for an underground LPG storage tank, construction methods shown in FIGS. 3(A) to 3(E) have already been proposed. .

The details of the construction method of this underground continuous wall are as follows.

First, as shown in Figure 3 (A), an excavator 1 (a wall drill excavator is shown as an example) excavates the ground using the muddy method (a method in which excavation is carried out in a stabilized liquid made of bentonite). After excavating a deep groove I11 of a predetermined width inside, the slime in the deep groove Ill is treated.

Next, as shown in FIG. 3(B), a reinforcing bar cage 2 assembled into a substantially rectangular cross-sectional shape is installed inside the deep groove 111, and joint boxes are placed on both sides of the cage in the width direction. 3 to hold this reinforcing bar cage 2 vertically.

This reinforcing bar cage 2 is assembled with main bars, transverse bars, column bars, and the like.

From this, as shown in Fig. 3(C), after inserting the tremie pipe 4 into the deep groove 1 (1) and pouring the concrete C, both the joint boxes 3 are removed and the preceding ground is placed. Build the inner wall Wl.At this time, as the concrete C is being poured, the stable if&L is sequentially extracted.

Next, as shown in FIG. 3(D), the excavator l is placed adjacent to one side of the previously constructed underground wall W1.
After excavating the next deep trench 112 using the muddy water method, one side of the previously constructed underground wall Wl, that is, the next deep trench 1 (2) is excavated on the side of the excavated side. Along the line, as shown in FIG. 3(E), while lowering the cleaning device 5,
One side of the underground wall Wl and its surroundings are cleaned to remove mud and slime adhering to the debris.

From this, after processing the slime etc. that has settled at the bottom of i'J i+II II 2, the above-mentioned work after inserting the reinforcing bar cage 2 is sequentially repeated to remove the underground continuous wall W.
Build.

According to such a construction method, there are many advantages such as the effect of preventing loosening of the excavated ground, the effect of preventing the generation of vibration and noise during excavation, and the simplification of construction.

[Problem to be solved by the invention] By the way, in such a conventional underground continuous wall construction method, when excavating the next depth 11*112 adjacent to the previously formed deep trench I11, the following Problems like this may occur.

That is, when a deep groove H is excavated with a drill, both sides of the groove H are formed into an arc shape in plan view.

Along with this, in the conventional construction method, the next deep groove 11
The excavation in step 2 is carried out after the underground wall Wl has been constructed in the previously formed deep trench I11, and must be carried out while avoiding interference with the previously constructed underground wall W1. Then, as shown in Figure 4, operate the excavator l so as not to contact the reinforcing bars that extend from the underground wall Wl to the underground wall W2 side in the continuous part of the adjacent double slope old ditch H2. Therefore, slime, dirt, etc. will remain in the residual portion T.

If a residual part T such as slime is generated in this way, when concrete C is poured into the next deep trench 1!2 and an underground wall W2 is horizontally constructed, as shown in FIG. Recessed cross-sectional defects K are formed on both sides of the wall W2, and in order to remove them, repair work must be carried out on the surface of the underground wall 12.

Therefore, in the past, there has been a desire to deal with the above-mentioned problems, and the present invention aims to solve the remaining problems in the conventional technology.

[Means for Solving the Problems] The present invention aims to provide a method for constructing an underground continuous wall that can effectively solve the above-mentioned problems. A deep trench of a specified width is excavated, a reinforcing steel cage is installed inside the trench, and then concrete is poured to construct the preceding underground wall, and then adjacent to one side of this previously constructed underground wall. Then, the excavator excavates the next deep trench, installs a reinforcing cage inside it, and then pours concrete 1, making the next underground wall continuous with the previous pond wall. A method for constructing an underground continuous wall in which, in a state where a next deep trench is excavated in one side of the preceding underground wall, a cleaning device is installed along one side of the underground wall. is lowered to clean the vicinity of one side of the underground wall, and a cutter provided in the cleaning device removes the residual portion formed on the inner wall between the two adjacent deep trenches.

[Function] According to the method for constructing an underground continuous wall according to the present invention, prior to constructing the next underground wall, a wall is attached to one side of the previously constructed underground wall. When the cleaning device is lowered to clean the vicinity of one side of the underground wall, the residual portion remaining on the inner wall of the deep trench is scraped off using a cutter provided in the cleaning device.

Thereafter, by pouring concrete into the next deep trench to construct an underground wall, a continuous underground wall with substantially smooth front and back surfaces can be obtained.

[Example] An example of the present invention will be described below with reference to FIGS. 1 and 2.

The basic steps in this embodiment are the same as those in the conventional construction method shown in FIG. 3, so the following description will incorporate FIG. 3, and common parts will be described using the same reference numerals.

First, a cleaning device suitably used for carrying out the construction method according to this embodiment will be explained based on FIGS. 1 and 2.

As shown in FIG. 1, this cleaning device 5 slides onto a T-shaped guide rail 6 that protrudes from the side of a previously constructed underground wall Wt along its length. A main body 7 that is movably mounted and constituted by a frame, an engaging member 8 provided on one side of the main body 7 and engaged with the flange portion 6a of the guide rail 6, and the main body a submersible pump 9 mounted approximately at the center of the main body 7; a cleaning pipe 11 connected to the submersible pump 9 and equipped with a substantially horizontal nozzle 10; and both sides of the main body 7. (the side portion on the inner wall surface side of the deep groove H) is configured by cutters 12 attached below, and a brush L3 attached near these cutters 12 toward the engaging member 8 side.

As shown in FIG. 1, the main body 7 is formed in such a shape that it can be inserted between the horizontal reinforcements 2a that constitute the reinforcing bar cage 2.

Moreover, each cutter 12 is \1 in this embodiment.
It is formed in a Z plate shape, and when the main body 7 is engaged with the guide rail 6 via the engagement member 8, the horizontal strip 2
It is attached at a position protruding from one end of the wall a and parallel to the wall at an interval approximately equal to the thickness of the underground wall ill.

Furthermore, the brush 13 is formed in such a length that it comes into contact with the end of the horizontal strip 2a when the main body 7 is attached to the guide rail 6.

On the other hand, a bracket 14 is integrally provided at the upper end of the main body 7, to which a wire 15 suspended from a crane (not shown) or the like is connected. , the cleaning device 5 is moved up and down along a guide rail 6. As this crane, for example, the crane used when inserting and installing the reinforcing bar cage 2 into the deep groove H is also used.

Next, a construction method of this embodiment will be explained.

In this embodiment, FIGS. 3(A) to 3(D)
The process shown in , that is, the depth iff to be excavated in advance
The underground wall W constructed in advance from the excavation process of tl l
The construction process of 1 and the subsequent excavation process of deep trench 1 (2) are the same as the conventional construction method.

This embodiment has a feature in the cleaning process performed after the excavation process shown in FIG. 3(D).

That is, when the next deep trench +12 is excavated on the side of the previously constructed underground wall Wl, both trenches 1! A residual portion 1'' as shown in FIG. 4, similar to the conventional method, is formed in the continuous portion of 112.

Here, the engaging member 8 of the cleaning device 5 is engaged with the guide rail 6 provided on the side of the constructed underground wall W1.

With the δL cleaning device 5 attached to the guide rail 6 in this manner, the cutters 12 provided on both sides of the cleaning device M5 are positioned oppositely above the residual portion T remaining on the inner wall surface of the deep groove H. .

From this, the cleaning device 5 is operated while jetting the cleaning liquid from the jet nozzle 10 provided in the cleaning pipe 11.
It is lowered along the guide rail 6 by its own weight.

By this operation, the double-sided vine 12 is moved so as to bite into each residual portion 'r, and these residual portions 'r are successively scraped off.

It is assumed that the slime and earth and sand scraped off in this way will stick to the reinforcing bars (horizontal reinforcement 2a) etc. located in the vicinity, but these slime and earth and sand are injected from the jet nozzle IO. The deep groove H(+(2)
dropped to the bottom of the

By performing this operation up to the bottom of the deep trench +12, both of the remaining portions T are removed and the scraped earth and sand is prevented from adhering to the reinforcing bars.

After this, if the next underground wall W2 is formed in the next K'tiSff II 2 and the underground continuous wall W is constructed,
Since the inner wall surface of the deep trench 112 is formed to be substantially smooth, the smoothness of the front and back surfaces of the underground continuous wall W after construction is ensured.

Therefore, repair work after constructing the underground continuous wall W is not required, making it possible to shorten the construction period and reduce costs.

Note that the above-mentioned embodiments are merely examples, and various changes can be made depending on the type and shape of the underground continuous wall to be applied, changes in construction procedures, differences in geology, etc.

For example, in the above embodiment, an example was shown in which the remaining portion T was removed by pressing the flat cutter 12 against the remaining portion T by the weight of the cleaning device 5. The cutter 12 may be vibrated.

Further, the method of guiding the t-shield device 5 is not limited to the above embodiment.

[Effects of the Invention] 2. As explained above, according to the method for constructing an underground continuous wall according to the present invention, the next underground wall can be constructed on the side of the previously constructed underground wall. When cleaning the vicinity of one side of the underground wall by lowering the cleaning device along one side of the previously constructed underground wall, The remaining part of the inner wall of the deep trench is scraped off using a cutter, and then concrete is poured into the next deep trench to construct the underground wall. By smoothing the wall surface, it is possible to obtain a diaphragm wall with smooth front and back surfaces, which makes it possible to construct a diaphragm wall with sufficient strength, and also makes it possible to construct a diaphragm wall with sufficient strength. This has excellent effects such as eliminating the need for later repair work, shortening the construction period and reducing costs.

[Brief explanation of the drawing]

In the drawings, FIGS. 1 and 2 show an example of a cleaning device suitably used for carrying out the present invention. FIG. 1 is a plan view, FIG. 2 is a side view, and FIGS. Figure 3 (E) is a process diagram for explaining the conventional underground wall construction method;
The figure is a plan view showing the condition of a deep trench excavated by the conventional construction method, and FIG. 5 is a cross-sectional view of the diaphragm wall constructed by the conventional construction method. DESCRIPTION OF SYMBOLS 1... Excavator, 5... Cleaning device, W... Underground continuous wall, H... Deep trench, T... Remaining part. 2...Reinforced cage, 12...Force, TarWl...Underground wall, C...Concrete,

Claims (1)

[Claims] An excavator excavates a deep trench of a predetermined width underground, a reinforcing cage is installed inside the trench, and then concrete is poured to construct the preceding underground wall. A next deep trench is excavated by the excavator adjacent to one side, a reinforcing cage is installed inside the trench, and concrete is poured to form the next underground wall on top of the previous one. A method of constructing an underground continuous wall in which the continuous underground wall is constructed in a continuous state, wherein, in a state where a next deep trench is excavated in one side of the preceding underground wall, the following deep trench is constructed along one side of the underground wall. The cleaning device is lowered to clean the vicinity of one side of the underground wall, and a cutter installed in the cleaning device removes the residual portion formed on the inner wall between the two adjacent deep trenches. How to build a diaphragm wall