JPH03208918A - Execution method for water impermeable film wall - Google Patents

Abstract

PURPOSE:To promote greatly execution efficiency by lapping the ends of water impermeable sheets having stopping pieces projected to the boundary between body sections and the end sections in a belt shaped channel to insert, and filling a material with high impermeability between opposite leak stopping pieces. CONSTITUTION:Leak stopping pieces 5 and 5 are projected right and left to the boundary between body sections 3b and 3b of impermeable sheets 3 and 3 and joint sections of the end sections 3a. After that, the impermeable sheets 3 and 3 are inserted into a belt shaped channel 2 by lapping the joint sections each other, and a material 6 with high impermeability such as asphalt mortar, etc. is filled between opposite leak stopping pieces 5 and 5. According to the constitution, pressure-welding work by a large scaled machine is not required, and the impermeable sheets 3 and 3 can be joined without having any trouble even in water or muddy water.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is a water-blocking membrane wall using a water-blocking sheet for construction of underground dams, water-blocking walls of waste treatment plants, water-blocking walls of dams, etc. Regarding construction methods.

[Conventional technology]

Conventionally, methods such as chemical injection, concrete replacement, and in-situ stirring and mixing methods have been used to construct impermeable walls.

However, chemical injection methods, in-situ stirring and mixing methods, etc. require a large construction area (volume), which is disadvantageous in terms of workability and cost, and even if concrete replacement methods are used, cracks, etc. must be taken into consideration. need to be widened.

In order to solve this problem, in recent years, a water-shielding membrane wall construction method has been used in which a water-shielding sheet is inserted into a groove to construct a water-shielding wall. According to this construction method, high water-blocking performance can be ensured even if the construction area is small (using the water-blocking sheet).

FIG. 6 shows an outline of this impermeable membrane wall construction method, in which a belt-shaped groove 2 is formed by excavating trenches with an excavator such as a chainsaw between circular guide holes 1 that have been previously excavated at appropriate intervals.
A water-blocking sheet 3 is inserted into this band-shaped groove 2, and a filler material 4 such as mortar is poured into the gap.

The optimal water-blocking sheet 3 is a sheet several millimeters thick, made of a non-woven fabric core and coated with rubber asphalt, and is rolled out into the band-shaped groove 2 as shown in the figure.

Further, the filling material 4 such as mortar may be filled with a tremie tube or the like.

[Problem to be solved by the invention]

By the way, in order to provide continuity to the water-blocking sheet 3, it is necessary to provide a joint portion 3c.

Conventionally, there are methods for bonding the joint portions 3c, such as by heat-sealing them together or by applying adhesive to the joint surfaces, but these methods require large-scale equipment and are difficult to do underwater. It may not be possible to use it in muddy or muddy water.

SUMMARY OF THE INVENTION An object of the present invention is to provide a water-shielding membrane wall construction method that eliminates the disadvantages of the conventional examples and allows continuity of a water-shielding sheet to be easily and reliably obtained.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention is a method of constructing a water-blocking membrane wall in which a water-blocking sheet is inserted into a belt-shaped groove and the surrounding gap is filled with a filling material such as mortar. The main idea is to provide leak-proofing pieces protruding left and right at the boundaries between parts, wrap the joint parts of the water-blocking sheet, and fill the spaces between the opposing leak-proofing pieces with a highly water-blocking material such as asphalt mortar. It is something.

[Effect]

According to the present invention, the crimping work is omitted by simply wrapping the joint parts of the water-shielding sheets together, so workability is greatly improved. However, if the material is filled with a highly water-shielding material, sufficient water-shielding properties can be expected.

〔Example〕

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

FIGS. 1 and 2 are plan views showing one embodiment of the water-blocking membrane wall construction method of the present invention.

First, to explain the water-shielding sheet used in the present invention, the water-shielding sheet 3 has an end 3a as a joint part with respect to the main body 3b, and there are pleats at the boundary between the end 3a and the main body 3b. Leak prevention pieces 5, which are crossing pieces, are provided to protrude from the left and right.

The water-shielding sheet 3 is, for example, a sheet several millimeters thick made of a non-woven fabric as a core material and coated with rubber asphalt, as in the past. It may be made of synthetic rubber or other different materials.Before installation, the leak-proofing piece 5 should overlap the end portion 3a or the main body portion 3b, and the entire water-blocking sheet 3 should be rolled up and transported. It does not cause any hindrance.

Next, the construction method of the present invention using such a water-blocking sheet 3 will be explained.

This is different from the conventional example in that a belt-shaped groove 2 is formed by excavating between the circular leading guide holes 1 which have been previously drilled at appropriate intervals using an excavator such as a chainsaw, and a water-blocking sheet 3 is inserted into the belt-shaped groove 2. are the same.

In this case, the ends 3a and the leak prevention pieces 5 are located in the guide hole l, but the ends 3a are lapped together in the guide hole 1, and the left and right leak prevention pieces 5 are expanded to form band-shaped grooves. 2
The boundary between the guide hole 1 and the guide hole 1 is closed.

After doing this, a material 6 having high water-shielding properties such as asphalt mortar is filled between the opposing leakage prevention pieces 5. In this case, the leakproof piece 5 acts as a backer and prevents the highly water-impermeable material 6 from flowing into the strip groove 2.

In addition, in the part of the belt-shaped groove 2, the water-blocking sheet 3 is
A gap around the main body portion 3b is filled with a filling material 4 such as mortar.

In this case as well, the leak prevention piece 5 acts as a packer, and the filler 4 can be placed separately for each water-blocking sheet.

In addition, in the above embodiment, the preceding guide hole 1 is required to excavate the strip groove 2 with a chain saw, and the preceding guide hole 1 is used to provide continuity to the water-blocking sheet 3. Depending on the type of the guide hole 1, it may not be necessary to provide the leading guide hole 1.

Even in such a case, the present invention makes it possible to connect the water-blocking sheet 3 at any position in the band-shaped groove 2 by expanding the leak-preventing pieces 5 as shown in FIG.

〔Effect of the invention〕

As described above, in the water-blocking membrane wall construction method of the present invention, when a water-blocking sheet is inserted into a band-shaped groove and the surrounding gap is filled with a filling material such as mortar, the ends of the water-blocking sheet are wrapped. Since the conventional crimping work is omitted,
There is no need for large-scale machinery, and there is no effect even in water or muddy water, greatly improving workability.

In addition, sufficient water-blocking properties can be expected by filling the joint with a highly water-blocking material, and there is no risk of problems occurring even if the lap width is insufficient or if they are separated from each other.

[Brief explanation of drawings]

1 and 2 are plan views of each process showing one embodiment of the impermeable membrane wall construction method of the present invention, Fig. 3 is a perspective view of the same as above, and Fig. 4 is a perspective view of the main parts of the impermeable sheet. FIG. 5 is a plan view showing another embodiment of the present invention, and FIG. 6 is a perspective view showing a conventional example. 1... Leading guide hole 2... Belt-shaped groove 3... Water shielding seam 1- 3a... End portion 3b... Main body portion 3C
... Fitting 4 ... Filler material 5 - Leak prevention piece 6
...Highly waterproof material

Claims (1)

[Claims] In the method of constructing a water-blocking membrane wall, in which a water-blocking sheet is inserted into a belt-shaped groove and a filler is filled in the gap around the sheet, leak-preventing pieces are protruded from side to side at the boundary with the joint at the end of the water-blocking sheet. A construction method for a water-shielding membrane wall, which is characterized by wrapping the joint parts of the water-shielding sheet together and filling a material with high water-shielding properties such as asphalt mortar between the opposing leakage prevention pieces.