JPH0657954B2 - Construction method of impermeable membrane wall - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a water-blocking membrane wall that uses a water-blocking sheet in the construction of an underground dam, a water blocking wall of a waste treatment plant, a water blocking wall of a dam, or the like. Regarding the construction method.

[Conventional technology]

Conventionally, a chemical injection method, a concrete replacement method, an in-situ agitation mixing method, etc. are used to construct the impermeable wall.

However, the construction area (volume) of the chemical injection method or in-situ mixing method is large, which is disadvantageous in terms of workability and cost. Need to be wide.

In order to solve this problem, in recent years, a water-impervious membrane wall construction method has been performed in which a water-impermeable sheet is inserted into a groove to construct an impermeable wall. According to this construction method, a high water-blocking property can be secured by the water-blocking sheet even if the construction area is reduced.

FIG. 6 shows an outline of such a water-blocking film wall construction method, in which the band-shaped groove 1 is formed by trench excavation with a chain cutter as disclosed in JP-A-64-80624 and JP-A-1-121491. The water-blocking sheet 2 is inserted into the band-shaped groove 1, and a filler 3 such as mortar is poured into the gap.

As the water-blocking sheet 2, a sheet having a thickness of several millimeters, which is made of a non-woven fabric as a core material and coated with rubber asphalt, is most suitable, and the sheet is pulled out from the roll-shaped groove 1 from a roll state as shown in the drawing.

The filling material 3 such as mortar may be filled with a tremie tube or the like.

[Problems to be Solved by the Invention]

By the way, when the water-impervious sheet 2 has a shallow depth, it is fed along a rod-shaped guide roller, and when the depth becomes deeper, a weight such as a steel bar is attached to the lower end to lower it. 1 has a narrow width, and when the depth increases, bending easily occurs, so that the leading end of the sheet 2 may contact the hole wall of the groove 1 or may be displaced in the horizontal direction, so that the sheet 1 cannot be inserted accurately.

Further, the water-impervious sheet 2 needs to be provided with the joint portion 2a in order to have continuity, and conventionally there are methods of heat-sealing each other or applying an adhesive to the joint surface to adhere them. This method requires a large-scale device and cannot be used in water or muddy water.

In addition to this, if the depth is large, it is difficult to secure and manage the lap width of the joint portion 2a.

An object of the present invention is to eliminate the disadvantages of the conventional example, and to insert the water-impermeable sheet smoothly and accurately to a predetermined depth of the band-shaped groove, and to easily and reliably obtain continuity of the water-impermeable sheet. To provide a wall construction method.

[Means for Solving the Problems]

In order to achieve the above object, the present invention can fold a short piece in the center of the band-shaped groove in a method of constructing a water-blocking membrane wall in which a water-blocking sheet is inserted into the band-shaped groove and the gap around the water-blocking sheet is filled. Vertically-shaped interlocking strips that are bound to each other are arranged side by side in the length direction of the groove at intervals, and the short pieces at the lower end are connected by a spacing member such as a bolt and arranged, and inserted into the groove. The water-impermeable sheet has a locking projection at the end of the joint, and by inserting this locking projection outside of the vertically long plate, the joint is wrapped and inserted between the vertically long plates, and the vertically long plate is pressed and brought into close proximity. The gist is to sandwich and fix the water-impervious sheet joint.

[Action]

According to the present invention, since the locking projection is projected to the outside of the vertically long plate, the water-impervious sheet does not come off the vertically long plate, and the locking projection moves along the edge of the vertically long plate. ,
It is possible to lower the water barrier sheet without difficulty.

In this way, when the water-impervious sheet is inserted into the band-shaped groove so that the joint portion at the end is inserted between the vertically long plates, the position is controlled by this vertically long plate, and the lap length of the joint portion can be reliably ensured.

In addition, the joints can be joined to each other simply by pressing the vertically long plates close to each other and sandwiching the water-impervious sheet joint, and the crimping work is omitted, so the workability is greatly improved and the effects of water, muddy water, etc. I do not receive it.

〔Example〕

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 to 3 are plan views showing an embodiment of the water-permeable film wall construction method of the present invention.

First, as in the conventional case, trenches are excavated in the ground by an excavator such as a chain cutter as disclosed in JP-A-64-80624 and JP-A-1-121491 to form a band-shaped groove 1, and the inside of the band-shaped groove 1 is formed. Vertically long plates 4 are arranged in parallel with each other in the longitudinal direction of the groove 1 with a space in the center. The vertical plates 4 are arranged at intervals to connect the water-impervious sheet 2 described later, and the length of the vertical plates 4 is the same as the depth of the band-shaped groove 1.

An example of the vertically long plate 4 is shown in FIG. 4, which is a comb-shaped short piece 4a that is foldably connected, and the short pieces 4a at the lower end are connected by a spacing member 5 such as a bolt.

As the material of the short piece 4a, a metal plate such as a steel plate, a wooden plate such as a control panel, and a synthetic resin plate having appropriate hardness are suitable. The short pieces 4a are connected to each other by a connecting tool 6 such as a ring or a coil.

As shown in FIG. 1, if two such vertically long plates 4 are juxtaposed and hung down in the band-shaped groove 1, then the water-impervious sheet 2 is inserted into the band-shaped groove 1 at that time. As shown in the figure, the joint portion 2a of the water-impervious sheet 2 is wrapped and inserted between the vertically long plates 4.

Since the locking projection 7 is formed at the end of the joint portion 2a of the water-impervious sheet 2 and the locking projection 7 is projected to the outside of the vertically long plate 4, the water impermeable sheet 2 is made up of the vertically long plate 4. Since the locking projection 7 moves along the end of the vertically long plate 4 without coming off, the water-impervious sheet 2 can be lowered without difficulty.

Then, as shown in FIG. 3, a cylindrical body made of the civil engineering sheet 8 is arranged on the outside of the vertically long plate 4, and the mortar 9 is poured into the civil engineering sheet 8 to inflate the same, as shown in FIG. The water shield sheet 2 is pressed by pressing the plates 4 to bring them close to each other.
The joint portion 2a of is clamped and fixed.

The short pieces 4a at the lower ends connected by the spacing members 5 such as bolts form a mountain shape only when their upper ends are close to each other, but the connecting portions between the short pieces 4a are freely formed in the upper portion. The water-impervious sheet 2 is bent and easily sandwiched.

After the water-impermeable sheets 2 are connected to each other via the vertically long plate 4 in this manner, the gap between the outer periphery of the water-impermeable sheet 2 and the band-shaped groove 1 is filled with a filler 3 such as mortar.

〔The invention's effect〕

As described above, the impermeable membrane wall construction method of the present invention, when the impermeable sheet is inserted into the band-shaped groove, and when the surrounding gap is filled with a filling material such as mortar, the impermeable sheet has a joint portion at the end. Since it is inserted into the band-shaped groove so as to be inserted between the vertically long plates, the position is controlled by the vertically long plates, and the lap length of the joint portion can be reliably ensured.

In addition, the joints of the water-impermeable sheets can be joined to each other simply by pressing the vertically long plates into close proximity and sandwiching the water-impermeable sheet joints, and the conventional crimping work with an adhesive material is omitted. However, it is not affected by water or muddy water.

[Brief description of drawings]

1, 2 and 3 are the first of the water-blocking membrane wall construction method of the present invention.
FIG. 4 is a plan view of each step showing an embodiment, FIG. 4 is a perspective view of a vertically long plate to be used, FIG. 5 is a perspective view of the vertically long plate in a pressing proximity state, and FIG. 6 is a perspective view showing a conventional example. DESCRIPTION OF SYMBOLS 1 ... Band-shaped groove 2 ... Water-blocking sheet 2a ... Joint part 3 ... Filler material 4 ... Vertically long plate 4a ... Short piece 5 ... Interval holding material 6 ... Connector, 7 ... Locking protrusion 8 ... Civil engineering sheet, 9 ... mortar

Claims (1)

[Claims] 1. A method for constructing a water-impervious membrane wall in which a water-impermeable sheet is inserted into a band-shaped groove and a gap is surrounded by a filler, in the center of the band-shaped groove, a short piece is foldably bound. -Shaped vertical plates are arranged side by side in the longitudinal direction of the groove with a gap, and the short pieces at the lower end are arranged by connecting them with a spacing material such as bolts, and the waterproof sheet inserted into the groove is a joint. Form a locking projection on the end of the part, and by inserting this locking projection outside the vertical plate, insert the joint part by wrapping it between the vertical plates.
A method of constructing a water-impervious membrane wall, characterized in that the vertically long plates are pressed close to each other to sandwich and fix the water-impervious sheet joint.