JPH03217517A - Construction of water-shield film wall - Google Patents

Abstract

PURPOSE:To obtain a water-shield wall of high accuracy by a method in which weights with hooks are fixed at an adequate interval to a banded trench bottom and dragged with the lopes of a water-shield sheet to draw the water-shield sheet into the banded trench. CONSTITUTION:A water-shield film wall is formed by tensely setting a water- shield sheet 2 in a banded trench 1. In this case, the banded trench 1 is excavated, weights 5 with hooks 4 are set at an adequate interval on the bottom of the trench 1, and the foots of the weight 5 are fixed with concrete 7. A cable 6 such as rope, piano wire, etc., is provided to the lower end of the sheet 2 and pulled through the hooks 4 in the trench 1 to draw the lower end of the sheet 2 into the bottom of the trench 1 tensely. The sheet 2 can thus be inserted with high accuracy to a given depth into the trench 1 for constructing a water- shield film wall.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is applicable to the construction of underground dams, impermeable walls of waste treatment plants, ice-blocking walls of dams, etc. Regarding construction methods.

[Prior Art] Conventionally, chemical injection methods, concrete replacement methods, in-situ stirring and mixing methods, etc. have been used to construct ice 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 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 properties can be ensured by using the water-blocking sheet even if the construction area is small.

Fig. 8 shows an outline of such a water-blocking membrane construction method, in which a trench is excavated with an excavator such as a chainsaw to form a band-shaped groove 1, a water-blocking sheet 2 is inserted into the band-shaped groove 1, and A filling material 3 such as mortar is poured into the gap.

The most suitable water-blocking sheet 2 is a sheet made of non-woven fabric as a core material and coated with comb asphalt, which has a thickness of several bars, and is rolled out into the strip groove 1 as shown in the figure. .

Further, although not shown, the filling material 3 such as mortar may be filled with a tremie tube or the like.

[Problem to be solved by the invention]

By the way, when the water-shielding seams 1 and 2 are shallow, they are curved so that they are drawn out along rod-shaped guide rollers, and although not shown, when the depth is deep, a weight such as a steel bar is placed in parallel along the lower end. I am trying to install it and take it down.

However, the band-shaped groove 1 is narrow and tends to bend as the depth increases, so the tip of the sheet 2 may come into contact with the hole wall of the groove 1 or shift in the horizontal direction, resulting in poor accuracy. In addition, the water-shielding sheet 2 must be provided with joints 2a to provide continuity in the horizontal direction, and these joints 2a must be joined together, but it is difficult to secure and manage the ramp width of the joints 2a. becomes difficult.

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 example and allows a water-shielding sheet to be inserted smoothly and accurately to a predetermined depth in a band-shaped groove.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a method for constructing a water-blocking membrane wall in which a water-blocking sheet is inserted into a strip-shaped groove and a filling material is filled in a gap around the strip-shaped groove. A weight with a hook or pulley on the top was placed at the bottom of the trench, concrete was poured at the bottom of the gutter, the hook or pulley was exposed, and the weight was hardened and connected to the lower end of the water-shielding sheet. The gist of this method is to insert a cable through the hook or trough and pull the lower end of the water-blocking sheet into the bottom of the band-shaped groove by pulling the cable.

[Function] According to the present invention, by pulling the cable, the end of the water-blocking sheet is pulled downward using the hook or pulley at the bottom of the band-shaped groove as a reaction force, and can be drawn directly to the bottom of the band-shaped groove.

In addition, since the retraction of the water-shielding sheet is also regulated by hooks or pulleys in the left and right positions, it is possible to reliably perform the lancing of the water-shielding sheet joint.

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

FIGS. 1 to 5 are side views showing one embodiment of the water-blocking membrane wall construction method of the present invention.

First, a trench is excavated in the ground using an excavator such as a chainsaw as in the conventional method to form a band-shaped groove l up to the impermeable layer (below the boundary α between the permeable layer and the impermeable layer). Prior to insertion, a weight 5 having a hook 4 on the top as shown in FIG. 6 is placed at the bottom of the strip groove 1. In this case, the cable 6 may be inserted in the middle of the hook 4 of the weight 5 in advance and suspended as it is.

Note that the weights 5 are placed at appropriate intervals at the bottom of the band-shaped groove 1, but if the weights 5 are located where the joint portion 2a of the water-blocking sheet 2 should be, they should be aligned with this position.

After arranging the weights 5 in this way, concrete 7 for foot protection is placed at the bottom of the strip groove 1 as shown in FIG.
The weight 5 is embedded and fixed in this concrete 7 in a state in which the weight 4 is exposed.

Next, as shown in FIG.
One end of a cable 6 such as a piano wire or wire is connected, and the other end of the cable 6 is towed on the ground with the middle of the cable 6 inserted through a fusoku 4.

Since the weight 5 of the hook 4 is fixed with concrete 7, the cable 6 can be retracted using the hook 4 as a reaction force, and as shown in FIG. It can be pulled directly to the bottom of the band-shaped groove.

In this way, once the preceding water-shielding notebook 2 is suspended in the belt-shaped groove 1, the next water-shielding sheet 2' to be joined to this water-shielding sheet 2 is similarly suspended in the belt-shaped groove 1, as shown in FIG. 1
hang it in.

At that time, if you use the same hook 4 to pull in the adjacent parts of the water-shielding sheets 2 and 2", all you need to do is select the joints of the water-shielding sheets 2" and 8 on the rope 6, and the joints will be connected. It is possible to ensure that the lantern in part 2a is correct.

Further, as another embodiment, as shown in FIG. 7, a pulley 8 may be provided in place of the hook 4 on the upper part of the weight 5.

By using the C-shaped pulley 8 in this manner, the cable 6 that is partially wound around the C-shaped pulley 8 can be pulled in smoothly with less frictional resistance with the pulley 8.

In addition, the water-shielding sheets 2, 2'' are separated in this way, and the gaps between the outer periphery of the water-shielding sheets 22' and the strip groove 1 are filled with mortar or the like (3) between the joint parts 2a. is the same as the conventional example.

[Effects of the Invention] As described above, the water-shielding membrane wall construction method of the present invention is effective when inserting the water-shielding saw 1- into a strip groove and filling the surrounding gap with a filling material such as mortar. To easily and smoothly insert a water sheet into a band-shaped groove to a predetermined depth and at a proper position with high precision.

[Brief explanation of drawings]

Figures 1 to 5 are side views of each process showing one embodiment of the water-blocking membrane wall construction method of the present invention, Figure 6 is a perspective view of a weight with a hook used, and Figure 7 is a side view of each process showing one embodiment of the water-blocking membrane wall construction method of the present invention. A perspective view of a weight with a pulley used in the embodiment, and FIG. 8 is a perspective view showing a conventional example. 1... Belt-shaped groove 2, 2''... Water-shielding sea} 2a... Joint part 3...
・Filling material 4... Funoku 5... Weight
6... Cable 7... Concrete 8
...Pulley Fig. 2 7 (Tsushi pulley 7 Fig. 4 Fig. 2 Fig. 5 Fig. 8 20)

Claims (2)

[Claims] (1) In the method of constructing a water-blocking membrane wall in which a water-blocking sheet is inserted into a band-shaped groove and the surrounding gap is filled with filler, a weight with a hook at the top is placed at the bottom of the band-shaped groove, and concrete is placed in a band-shaped groove. This weight is cast at the bottom of the groove and the hooks are exposed, and the cables connected to the ends of the water-blocking sheet are inserted through the hooks, and the water-blocking sheet is pulled by the cables. A method of constructing a water-blocking membrane wall that is characterized by being drawn into the bottom of a band-shaped groove. (2) In the method of constructing a water-blocking membrane wall in which a water-blocking sheet is inserted into a band-shaped groove and the surrounding gap is filled with filler, a weight with a pulley on the top is placed at the bottom of the band-shaped groove, and concrete is placed in the band-shaped groove. This weight is cast at the bottom of the trench and the pulley is exposed, and the weight is hardened, and the rope connected to the end of the water-shielding sheet is wound around the pulley, and the water-shielding sheet is pulled by the rope. A method of constructing a water-blocking membrane wall that is characterized by being drawn into the bottom of a band-shaped groove.