JPS62291317A - Quick construction of wide-width underground wall - Google Patents

Abstract

PURPOSE:To shorten the time of operation to a great extent by a simple constructing method in a method in which, the ground where a parallel two- armed coupler is to be penetrated is softened, a steel sheet pile is driven into the ground, and concrete is placed. CONSTITUTION:The grounds 8a and 8b for penetrating steel tubular sheet piles are softened by a long-drill excavation method, and a steel sheet pile 1 is driven into the ground by hammer. The steel sheet piles 1a-1c are orderly driven and coupled, and the inside grounds 11a-11e are excavated at adequate time. The excavated soil is discharged and concrete is placed. The wall faces of the holes 11a-11e are attached with lath or expandable metals to increase the bonding strength of concrete. The mechanical strength and water-stopping performance of the steel tubular sheet piles can be improved, permitting wide and long underground wall to be constructed.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for constructing underground walls, particularly wide underground walls, in the fields of civil engineering and construction.

[Conventional technology]

Civil engineering, l! In the field of construction, underground walls are often constructed for earth retaining, foundations, or pinto sections, and in order to handle especially large loads, it is necessary to construct wide underground walls with thick walls and a large construction depth. required.

As a method of constructing such wide underground walls,
Invention described in Publication No. 5-68921 (hereinafter referred to as invention A)
It has been known.

This method involves manufacturing a box-shaped guide steel frame by welding eight partition plates between two water-stop steel plates that have a locking part at one end and a guide part at the other end, and then attaching the guide steel frame to a pre-excavated site. This is a method in which the guide steel frame serves as an interlocking pipe, a water stop plate, and a joint, so construction is simple and the construction period is short.

[Problem that the invention seeks to solve]

Invention A is an excellent method for the purpose of constructing a wide and deep underground wall. Since the material must be charged and connected carefully so as not to bend, the construction time becomes longer and special measures are required to prevent the excavated trench from collapsing, which poses an issue in terms of construction cost. is left behind.

[Means for solving problems]

The present invention provides a method for constructing a wide underground wall that is easy to construct, takes extremely short work time, and is sturdy.The present invention provides a method for constructing a wide underground wall that is easy to construct, takes extremely short work time, and is strong. In order to do so, the gist is a method of weakening the planned penetration site of the parallel double-arm joint in advance, or driving or press-fitting the steel pipe sheet pile while weakening the area, excavating it, and then filling it with concrete.

[Effect]

Following the structure and operation of the steel pipe sheet pile used in the method of the present invention, the method of the present invention will be explained in detail.

FIG. 4 is a plan view of the steel pipe arrow vi, 1 according to the present invention, in which joints 48 to 4d are attached to the corners 3a to 3d of the square steel pipe 2, respectively, and the axis X passing through the center of the flange walls 2a and 2b of the square steel pipe 2
+ -X +, X! It is fixed along the Xz direction by a welding method.

In the present invention, as mentioned above, the joints 4a, 4b and 4c are mounted in parallel on each side of the steel tube.

4d is called a parallel double arm joint.

FIG. 5 is a plan view of a steel pipe 417 in which parallel double-arm joints 68 to 6d are fixed to a cylindrical steel pipe 5, and the parallel double-arm joints 6a to 6d are connected to a center line Xs passing through the axis of the cylindrical steel pipe 5.
Parallel lines X s −X s symmetrical about Xs.

It extends from both sides of the cylindrical steel pipe 5 along the lines X and -X.

The parallel double-arm joints 4a to 4d and 6a to 6d are constructed by vertically cutting straight & lI steel sheet piles produced by rolling into halves, and are superior to other joints such as round steel pipes or round steel pipes in terms of joint strength, water-stopping properties, and workability. Much superior to shaped steel or steel plate joints.

Since the steel pipe sheet pile according to the present invention is constructed as described above, the desired width (wall thickness) can be freely selected by selecting steel pipes with the desired outer diameter for constructing particularly wide underground walls. I can handle it.

Next, during pouring, in the invention A, there is a high risk that the welded part between the water stop steel plate and the partition steel plate will be damaged during pouring, but the steel pipe sheet pile 1.7 of the present invention has a main body made of steel pipe 2.5, so it is difficult to , has a very large resistance to compressive force, tensile force, or twisting force applied to the steel pipe body from the inside and outside, so there is no need to soften the planned penetration site of the #A pipe body part (i.e.) 121 pipe part in advance. , the fact that the strength of this m9 portion is high, that is, there is no bending, has the effect of reducing damage to the welded joint of the parallel double-arm joint.

FIG. 1 is a plan view showing the procedure for driving steel pipe sheet piles 1. Before driving, the planned penetration areas 8a and 8b, indicated by the broken lines of the parallel double-arm joints 4a to 4d, are drilled using a long drill method, such as an earth auger. It is softened by an excavation method using a jet cutter or the like, and then pipes 11 and 1 are driven or press-fitted using a hammer or pipe rake.

In the present invention, softening refers to soil modification in which earth and sand are not actively removed, such as by drilling with the aforementioned earth auger or the like.

Next, Figure 2 shows steel pipe arrow 4. A high-pressure water injection nozzle lO is installed vertically in the vicinity of the tip claw part 9 of the parallel double-arm joint 4c of Fi1,
It is a partial cross-sectional perspective view showing the construction procedure of driving the steel pipe sheet pile 1 while weakening the planned penetration site by injecting high-pressure water from the tip 10a toward the lowest end 9a of the claw portion 9.

According to this construction procedure, it is possible to drive the steel pipe sheet pile without damaging or bending the parallel double-arm joint (maintaining its normal form).

FIG. 3 shows a plan view of the underground wall 50 constructed according to the casting procedure shown in FIG. 1 or 2 above.

Reference numerals la to 1c are steel pipe sheet piles that are successively cast and engaged, and their inner cavities 11a to 118 are excavated during or at an appropriate time after casting to remove soil and fill with concrete.

If lath, expanded metal, or the like is applied to the wall surface of the inner cavity 1ta-ne, the adhesion strength of concrete increases, and the mechanical strength i of the underground wall 50 can be increased.

【Example〕

The main body is a rectangular steel tube with an approximately square cross section and an outer diameter of 600 x 600vw, and the double arm joint is a half piece of straight steel sheet pile with a width of 28 mm.
0mm, length 20m, and welded to each corner of the square steel pipe to produce a steel pipe sheet pile with a construction depth of 20m.

An underground wall with a length of 40 m was constructed, but there were no accidents involving broken or damaged joints, and the construction period was successfully shortened by about 35% compared to the method of invention A.

In addition, as another example, we manufacture steel pipe sheet piles whose main body is square steel pipes with an outer diameter of 1000 x iooomm, and the construction depth is 30 m.
.

An underground wall with a length of 100 m was constructed, and in this case it was completed in 50% of the construction time using the invented method.

Although efficiency generally varies depending on the location of the planned site, the method of the present invention can shorten the construction period by 20 to 60% compared to the conventional method.

〔Effect of the invention〕

The construction method of the present invention does not require full-scale excavation or removal of earth and sand, so construction is quick.
In addition, the steel pipe sheet piles that are the building blocks for underground walls are mechanically strong and have good water-tightness, so wide and long underground walls can be constructed economically.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the pouring procedure according to the method of the present invention;
Figure 2 is a construction procedure using a shoko water injection nozzle, Figure 3 is a schematic plan view of an underground wall constructed by the method of the present invention, and Figures 4 and 5 are steel pipe sheet piles used in the method of the present invention. FIG.

Claims (1)

[Claims] 1. When constructing a wide underground wall by erecting steel pipe sheet piles with parallel double-arm joints on both sides, weaken the area where the parallel double-arm joints are planned to penetrate in advance, or drive the steel pipe sheet piles while weakening the area. Alternatively, a method for quickly constructing wide underground walls is characterized by press-fitting, excavating, and then filling with concrete.