JPH0611977B2 - Impermeable material - Google Patents

Description

Description: [Industrial field of use] The present invention relates to a water-impervious material used in water-impervious construction for preventing water leakage in the field of civil engineering.

In the field of civil engineering, it is necessary to carry out water shielding work on reservoirs, water storage facilities, (industrial) waste storage facilities, irrigation facilities, irrigation canals, etc. Needless to say, sufficient water impermeability must be achieved by such construction, but other than that, construction is required to be simple, quick, and reliable, and the cost is also preferably as low as possible.

[Prior Art] Conventional water-blocking work is performed by spraying a soil-based material with a low water permeability, which is mainly composed of natural swelling clay, or an artificial waterproofing material such as a waterproof sheet, asphalt, Waterproof concrete or the like has been used alone or in combination as a water-impervious structure.

Although the waterproof sheet has excellent waterproof performance, the preparatory process and laying process before installation are not easy and the material cost is high. Asphalt or its composites and concrete are not easy to repair when they are damaged by cracks or other ground changes. Also, the waterproof sheet, asphalt, and concrete all have a certain shape and size, but
Water leakage from the connection between these units is a major defect, and construction to prevent this is extremely difficult.

Natural swelling clay can create an impermeable layer that is well compatible with the ground, but when it is used alone in a granular form, it is not easy to lay it to a specified thickness, Careful construction is required and experience is required. Instead of careful construction, it is possible to achieve its water impermeability by using a much larger excess of swelling clay than necessary.
Material costs are high and not economical. Further, when used by mixing with other materials, the selection of other materials and the amount used are problems, and a specific mixing operation is required. Furthermore, when using a granular waterproof material, it is difficult to construct slopes and corners of 25 ° or more and special operations are required.

[Problems to be Solved by the Invention] An object of the present invention is to use natural swelling clay as a main material, solve the above-mentioned problems in construction, and ensure impermeable water with simple construction. The purpose is to provide a water blocking material from which layers can be made. That is, according to the present invention, it is possible to carry out the water-shielding work by a simple construction method in which the factory-manufactured products having a predetermined shape are lined up on site and covered with soil, and yet a very excellent water-shielding effect is achieved. Provide a water barrier material that can

[Means for Solving the Problems] The water-blocking material of the present invention comprises a matrix composed of a swelling clay bonded with a extensible binder and embedded in the matrix or on one outer surface of the matrix. It is characterized by comprising a core material of a perforated or reticulated sheet which is joined and has extensibility.

A typical swelling clay is bentonite, but other natural minerals such as montmorillonite, hectorite, saponite, hydelite, fluorohectorite, artificial minerals such as laponite and dimonite are also used as swelling clay in the present invention. be able to.

A extensible binder means a binder that allows a certain degree of elongation of the matrix when tension is applied to the matrix. A latex such as isoprene rubber latex or butadiene rubber latex can be used as the extensible binder. In addition, as solid rubber, isoprene rubber, butadiene rubber, ethylene-
Propylene rubber, etc., liquid polyisoprene, liquid polybutadiene, liquid styrene-butadiene rubber, and polystyrene-based, polyolefin-based, polyester-based, and thermoplastic elastomers as thermoplastic elastomers may also be used in the present invention as binders having extensibility. it can.

A stretchable perforated or reticulated sheet means a sheet having a large number of openings or a reticulated sheet, which can be stretched to some extent when a tension is applied to the sheet. For example, if a sheet made of plastic such as polyvinyl chloride or polyethylene is provided with a large number of openings and the total area of the openings is sufficiently large with respect to the total area of the sheet, such a sheet exhibits extensibility. Therefore, such a sheet can be used in the present invention as a perforated sheet having stretchability. Also, a thread formed of natural or synthetic fibers or a sheet formed by meshing a metal wire into a net-like form has stretchability and can be used in the present invention. A perforated sheet made of plastic is a particularly suitable sheet because it has a property of retaining the shape of the water-impervious material.

The binder is preferably used in a proportion of 10 to 20% by weight based on the swelling clay. Further, additives usually used for the swelling clay, for example, sodium tripolyphosphate, sodium pyrophosphate and the like can be added in a proportion of 0.5 to 5.0% by weight.

The core material is preferably embedded in the matrix, but in some cases, it may be bonded along one outer surface of the matrix.

[Example] An example of the water blocking material of the present invention is shown in FIG. This comprises a matrix 1 composed of swelling clay and a binder, and a single layer core material 2 embedded therein. In the figure, a part of the core material is projected to the outside of the matrix, but this is convenient for transporting and constructing the water blocking material.

The water-blocking material shown in FIG. 1 can be manufactured as follows. First, a mixture of swelling clay with a binder added and mixed is divided into two, and as shown in FIG. 2, half 1'is formed into a sheet and placed on a support (not shown). Core material 2
And the remaining half 1 ″ of the clay-binder mixture is placed on it in sheet form. When this assembly is pressed from above with a constant pressure and kept in that state for a certain period of time,
Swellable clay is bound by a binder to form a matrix 1
(FIG. 1) is formed, and at the same time, the core material 2 is joined to the matrix to form a plate-shaped water-impervious material. Some heat may optionally be applied to the assembly during or after pressing.

2 (a) to (c) show an example of the core material. (a) is an example of a reticulated sheet, and (b) and (c) are examples of a perforated sheet having a large number of openings. Perforated sheets can be made by punching or, if the sheet material is plastic, by injection molding.

The water blocking material of the present invention, as shown in (a) to (h) of FIG.
(a) flat plate shape, (b) block shape, (c) square tubular shape, (d) frame shape, (e)
It can be formed into various shapes such as a circular tube shape, (f) ring shape, (g) curved plate shape, and (h) L-shaped plate shape. These various shapes are selectively used according to the situation of the construction site, which will be described in more detail later.

When the water-blocking material has a large thickness as shown in FIG. 4 (b), it is preferable to use a plurality of layers of core material. The impermeable material is
It is shaped into a size that is convenient for transportation and construction. For example, in the case of the flat plate shown in FIG.
m, width 30 to 100 cm, thickness 3 to 7 mm is preferable, and in the case of the block shape shown in Fig. 4 (b), length 20 to 40 cm, width 10
The thickness is preferably -20 cm and the thickness is 5-10 mm.

[Operation] The construction of the water-impervious material of the present invention can be carried out by directly using conventional common techniques such as laying tiles, stacking blocks, and stretching sheets depending on the situation of the construction site.

In the case of waterproofing work on a flat part, a sheet-shaped or block-shaped water-impervious material is laid on the bottom of the excavation part. In that case, it is arranged so that the matrix portions of the adjacent water-blocking materials are as close to each other as possible. When the core material protrudes to the outside of the matrix, the adjacent matrix of the water blocking material is superposed on the protruding portion of one water blocking material. In some cases, the projecting portion may be cut off before construction. The thickness of the sheet is determined according to the geological condition of the construction site. When the geology is in a normal wet condition, it is preferable to use a sheet-shaped water-impervious material having a thickness of about 7 mm. For soft or gravel ground, the thickness of the sheet should be about 20 mm. Also, in a place with a lot of water seepage, the thickness is about 50 mm.
It is preferable to use a block-shaped water-blocking material of a certain size. After laying, excavated soil is compacted on the upper surface of the impermeable material layer to protect the surface.

After the construction, if the swelling clay in the water-blocking material comes into contact with groundwater, rainwater, seepage water, etc., it will hydrate and exhibit a swelling phenomenon. This fills the voids in the water-blocking material and further expands outward to fill the voids between adjacent water-blocking materials. The extensible core and the extensible binder allow such water-barrier material to expand outward. The swollen portion is highly sticky, and since it is in the form of gel, it completely blocks the passage of water after swelling.

The core material serves as a support material for the matrix during transportation and construction, but it supports the swelling clay even after it gels after construction, and prevents the matrix portion from flowing out even in places where there is a great amount of underground underground water, For this reason, a perfect water-blocking effect is achieved over a long period of time.

When constructing a vertical impermeable wall using the impermeable material of the present invention, it is convenient to stack blocks formed into blocks. After excavating soil on the front, back, and top of the back wall after the blocks are piled up, a protective layer is created. When water-impervious construction is performed on the inclined surface using the water-impervious material of the present invention, a rhomboid block shaped to fit the inclination may be used. For the construction of the corners, a flat plate can be used by bending it, but it is convenient to use an L-shaped one as shown in FIG. 4 (h).

Gas venting pipes and drainage pipes may be installed through the impermeable layer in reservoirs and other construction work. In this case, a water-impervious material molded to match the size and shape of the penetrating pipe is used. In the case of a circular pipe, the water-blocking material is molded into the shape shown in Fig. 4 (e) or (f), and in the case of a square pipe, the shape as shown in Fig. 4 (c) and (d). It is possible to prevent water from leaking from the gap of the mounting portion by fitting it into the penetrating portion.

[Effect] The water-blocking material of the present invention effectively utilizes the excellent water-blocking function of the swelling clay, and eliminates the conventional drawback that the construction is difficult. Since the matrix and the core material that are bound by the binding material are integrated to form a unit, the handling is convenient at the time of transportation and construction, and the scattering of clay is also prevented.

It is possible to reliably perform construction by simple operation of arranging or stacking units created in the optimum shape according to the situation of the place to be constructed, especially the ground, geology, and structure at the site, and also on steeply sloping land It can also be easily installed. Since the construction method is simple and less material is wasted, the construction cost per unit area is low.

Since the binder having stretchability and the core material having stretchability are used, the swelling clay can easily expand to fill the gap between the units when absorbing water after construction,
Excellent water impermeability of the connection is thus achieved.

[Brief description of drawings]

FIG. 1 shows an example of the water-impervious material of the present invention, FIG. 2 shows an example of the manufacturing process of the water-impervious material of the present invention shown in FIG. 1, and FIG. 3 shows the core material used in the present invention. Examples are shown, and FIG. 4 shows various shapes of the water-blocking material of the present invention. 1,1 ', 1 ": Matrix 2: Core material

Claims (3)

[Claims] 1. A matrix comprising a swellable clay bonded with a extensible binder and an extensible perforated or reticulated sheet embedded in the matrix or joined to one outer surface of the matrix. A water-impervious material that is made of a core material. 2. The water-blocking material according to claim 1, wherein a part of the core material projects to the outside from a side portion of the matrix. 3. The water-blocking material according to claim 1, which is in the shape of a flat plate, a hollow prism or a hollow cylinder.