JPS604958Y2 - Water-stop structure for underground storage tanks - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an underground tank for storing LNG, LPG, crude oil, etc., and more specifically, to a water stop structure that prevents groundwater from entering the tank.

Conventionally, underground tanks have generally been made of concrete, and waterproofing has been performed only at localized locations such as target areas using water stop plates against infiltration of groundwater.

However, if repeated loads such as earthquakes cause displacement at localized locations such as joints, the water stop plates will break and groundwater will infiltrate into the tank through these gaps.

In addition, after the concrete that forms the tank is placed, if the hardening concrete undergoes a sudden temperature change, temperature stress will occur due to the temperature difference between the inside and outside, causing cracks, and groundwater will leak into the tank through these minute gaps. There are problems such as infiltration.

This invention addresses the above-mentioned conventional problems, and its purpose is to provide a water-stop structure that prevents groundwater from seeping into an underground tank.

An embodiment of this invention shown in the drawings will be described below.

As shown in the figure, an underground tank 1 is constructed after excavating the inside of an annular earth retaining wall 2, and a side wall 3 of the tank is surrounded by the earth retaining wall 2 and is made of concrete.

Further, a bottom plate 4 is disposed below and adjacent to the side wall 3 of the tank.

That is, the peripheral edge of the bottom plate 5 is formed with a horizontal end surface 4a that contacts the lower surface 3a of the side wall 3 and a vertical end surface 4b that contacts the lower inner surface 3b of the side wall 3.

A water stop plate 5 is interposed between the lower surface 3a of the side wall 3 and the horizontal end surface 4a of the bottom plate 4.

The present invention is an underground tank having the above structure, in which a water-stopping sheet material 7 is interposed between the earth retaining wall 2 and the side wall 3, and the water-stopping sheet material 7 covers the outer surfaces of the side wall 3 and the bottom plate 4 in a bag shape. The reason is that it is formed integrally so as to cover it.

That is, after excavating the inside of the earth retaining wall 2 cast in an annular shape, the water-stopping sheet material 7a is attached to the inner surface of the earth retaining wall 2,
Thereafter, the concrete side wall 3 is formed so as to be surrounded by the earth retaining wall 2.

Next, a water-stopping sheet material 7b is laid on the entire surface of the base 6, and is adhered integrally to the lower part of the water-stopping sheet material 7a interposed between the earth retaining wall 2 and the side wall 3 to maintain watertightness. , and then a concrete bottom slab 4 is formed.

As the sheet material 7, a wide variety of materials can be used, such as rubber and plastic, which have waterproof properties and can be bonded to a concrete surface by adhesive or baking.

As described above, according to the present invention, by integrally forming a water-stop sheet material on the outer surface of the side wall and bottom plate of the tank, water-stop plates installed at localized locations such as joints of the tank can be prevented by external loads, etc. In addition, the difference in temperature between the inside and outside of the concrete during hardening causes cracks in the concrete, which can prevent groundwater from entering the tank through these gaps.

In addition, according to the present invention, a double water-stop structure consisting of a water-stop plate and a water-stop sheet material can be obtained, and the infiltration of underground water, which is a problem especially when storing low-temperature storage materials such as LNG and LPG, is prevented. In addition, there is an earth retaining wall on the outside of the water-stopping sheet material, so the surrounding soil water pressure does not directly act on it, so the water-stopping function can be maintained over time.

Furthermore, if a water-stopping sheet material is installed on the outer surface of the side wall without installing an earth-retaining wall, construction would be extremely difficult, but in this invention, the side wall is formed by pasting a water-stopping sheet material on the inner surface of the earth-retaining wall. This has the advantage of eliminating construction difficulties.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an underground storage tank according to the present invention. 1...Underground tank, 2...Earth retaining wall, 3
...Side wall, 3a...Bottom surface of side wall, 3b
... lower inner surface of side wall, 4 ... bottom plate, 4
a...Horizontal end face of the bottom plate, 4b...Vertical end face of the bottom plate, 5...Water stop plate, 6...Base, ? , 7a, 7b...Waterstop sheet.

Claims (1)

[Scope of utility model registration request] In a water-stop structure for an underground tank in which a water-stop plate is interposed between the side wall and the bottom plate of the tank, the side wall is surrounded by an earth retaining wall, and a water-stop sheet material is interposed between the side wall and the earth retaining wall. , and the water-stopping sheet material is integrally formed so as to cover the outer surface of the side wall and the bottom plate in a bag-like manner.