JPH069057Y2 - Waterproof sheet for civil engineering work - Google Patents

Description

[Detailed Description of the Invention] << Industrial Application Field >> The present invention relates to a tarpaulin for civil engineering work used for residential land development, soft ground improvement work, revetment work, and the like.

《Prior art》 A waterproof sheet as a civil engineering stabilization material has the advantages of being cheaper and superior in water impermeability than natural materials, being easy to control the thickness, and being simple to implement. Therefore, the range of application is expanding more and more.For example, it is used as backfill material for articulated blocks and rockfill layers in revetment work, and earth and sand flow out through crevices such as block joints and are scoured. It is used to prevent the ground and stabilize the ground. As the sheet material, in addition to water-blocking properties, flexibility and durability that can withstand some uneven settlement are required. For example, in the case of slopes, vinyl chloride,
A polyethylene sheet or the like is suitable.

FIG. 3 shows an example of using the waterproof sheet, and the waterproof sheet a is
It is used as a backfilling material for the continuous blocks c laid on the slope b, and the blocks c are sequentially stacked with the sheet a covering the slope b formed by cutting or embankment. The block load is dispersed and kept stable, and the water entering from the block joints is completely blocked. As shown in FIG. 4, the waterproof sheet a has a structure in which vinyl chloride d, felt e, and cloth material f are laminated, and the water-blocking vinyl chloride d in the lower layer is formed by the cushioning felt e and cloth material f. By covering it, the vinyl chloride d is prevented from being damaged by the block c and the block c can be stably installed. The cloth material f is provided to protect the felt e by preventing the felt e from fraying.

<Problems to be solved by the invention> The conventional waterproof sheet has a single-layer structure composed of only a water-impervious layer such as vinyl chloride, while a block or the like is provided on the slope side due to the cushioning effect of the felt. It is easy to fit in and is more stable, and the installation strength of the structure itself such as a block can be improved.

However, in the case of the waterproof sheet, a relatively thick felt has to be used because of its cushioning property and the like, so that it is heavier than a waterproof sheet having a single-layer structure. Therefore, in the slope covering work and the like, more force than apparent is required. In addition, the felt requires a cloth material to prevent fraying, which increases the cost, and when the felt is integrated with the water-blocking synthetic polymer sheet using an adhesive, the felt is peeled off. Or
Not only is it easy to cut, but the workability also deteriorates.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a waterproof sheet for civil engineering work that can eliminate the risk of the buffer layer peeling off from the water-impervious layer and improve workability. And

<< Means for Solving the Problems >> In order to achieve the above object, the present invention comprises a waterproof sheet having two layers of a water-impervious layer and a buffer layer integrally provided on the surface thereof, and both layers of the waterproof sheet. Is composed of a synthetic resin material of the same system, the water-blocking layer side is formed of a non-foaming layer, and the buffer layer side is formed of a foaming layer.

<Operation> According to the waterproof sheet, in addition to the cushioning effect of the foam layer on the structure such as the block, since both layers are firmly integrated, workability at the construction site is also improved,
There is no peeling of the buffer layer from the impermeable layer.

<Example> An example of a waterproof sheet for civil engineering work according to the present invention will be described below with reference to the drawings.

1 is a perspective view showing a waterproof sheet for civil engineering work to which the present invention is applied, and FIG. 2 is an enlarged sectional view showing the sheet structure. In these figures, a waterproof sheet 1 as a civil engineering material has a structure in which a buffer layer 3 is integrated with the surface of a water-impervious layer 2 located below. Polyvinyl chloride is used as a material for both layers 2 and 3, and the water-impervious layer 2 is a non-foaming layer, whereas the buffer layer 3 is a foaming layer provided by foam molding. ing.

Here, as the water-impervious layer 2, one formed into a thickness of about 0.5 to 1.5 mm is used like the conventional water-impervious synthetic polymer sheet, and the buffer layer 3 is formed on the surface of the water-impervious layer 2. The foamed layer is continuously formed at the time of forming the sheet or in a post process, and is firmly integrated. In this case, the foaming layer is set to an arbitrary foaming ratio, so that the same cushioning properties as those of the conventional cushioning felt can be obtained and the weight is light as a whole. Also, by appropriately changing the expansion ratio, etc.
The thickness and cushioning property of the buffer layer 3 can be set to an optimum state according to the application situation.

According to the waterproof sheet 1 formed in this way, as compared with the case where the felt is integrated with the conventional water-impervious layer by an adhesive,
Not only is the formation of the buffer layer 3 facilitated, but the bonding strength is greatly improved, so that peeling of the buffer layer 3 is less likely to occur.

The present invention is not limited to the polyvinyl chloride, and it goes without saying that a waterproof sheet having a foamed layer and a non-foamed layer can be obtained by using, for example, polyethylene.

<< Effects of the Invention >> As described above, according to the waterproofing sheet for civil engineering work of the present invention, in addition to the cushioning effect of the foam layer on the structure such as the block, the two are firmly integrated so that they can be carried easily. And slope surface covering work can be performed efficiently, and the peeling of the buffer layer from the water impermeable layer is eliminated. In addition, not only the durability is improved as a whole, but also the weight is reduced, and the cost is reduced by eliminating the need for cloth material. Excellent overall performance can be obtained.

When the present invention is used for revetment work and as backfill material for articulated blocks or rockfill layers, a non-foamed layer is installed directly on the slope, providing sufficient water impermeability to prevent gaps such as block joints. Surely prevent soil and sand from flowing out and being scoured, and at the side of the articulated block and rockfill layer,
Since the foam layer is located, the shock received by these articulated blocks and the rockfill layer can be reliably buffered.

[Brief description of drawings]

FIG. 1 is a perspective view of a tarpaulin for civil engineering work shown as an embodiment of the present invention, FIG. 2 is an enlarged cross-sectional view showing the structure of the sheet, and FIG. 3 is one example of a tarpaulin for civil engineering work as a conventional example. FIG. 4 is a schematic view showing a usage example, and FIG. 4 is a sectional view showing the structure of the sheet. 1 ... Waterproof sheet, 2 ... Water-impervious layer (non-foamed layer), 3 ...
Buffer layer (foam layer).

Claims (1)

[Scope of utility model registration request] 1. A waterproof sheet is composed of two layers, a waterproof layer and a buffer layer integrally provided on the surface of the waterproof sheet. Both layers of the waterproof sheet are made of the same type of synthetic resin material, and the waterproof layer is provided on the waterproof layer side. A waterproof sheet for civil engineering, comprising a non-foamed layer and a foamed layer on the buffer layer side.