JPS632507Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to drain paper used for improving soft ground.

Conventionally, as shown in FIG. 6, drain paper has been used in which grooves 3 on both sides of a corrugated sheet 2 are closed with water-permeable sheets 1.

However, when the above-mentioned drain paper is subjected to excessive pressure from the soil side or when it is necessary to mechanically pressurize and dewater the soil for the purpose of highly improving the soil bearing capacity, the water-permeable sheet 1 is damaged by the pressure from the soil side. The sheet was pushed into the groove 3, causing breakage of the sheet 1 and narrowing of the groove 3, resulting in the loss of its function as a drain paper.

Therefore, as shown in FIG. 5, the present applicant has formed a substrate 4 by blocking the openings on one side of a corrugated sheet 2, which has parallel grooves 3 and 3a alternately formed on both sides, with a water-permeable sheet 1. A water passage hole 6 is opened in the groove 3a whose surface is closed, and the substrate 4 is folded in half, or the two substrates 4 are stacked and the protrusions between the opposing grooves 3 and 3 are formed in each groove 3. proposed a drain paper with 5 facing each other (Utility Application No. 56-145946 (Utility Model Application No. 58-50135)). When this drain paper is placed in the soil, each protrusion 5 engages with the other groove 3 due to earth pressure, and a narrow passage parallel to the groove 3 is formed between the protrusion 5 and the groove 3. Water holes 7 are formed, and even if the sheet is damaged or the grooves 3 are narrowed, water absorption capacity can be maintained from the water holes 6 through the water passages 7, and the paper does not lose its function as a drain paper.

However, in the case of the above-mentioned drain paper, the side walls 51a, 51a of the protrusions 5 are inclined to expand outward at the tip side, and each protrusion 5 bites into the mating groove 3, so that the protrusions or grooves are formed by earth pressure. The walls of the strips 3 were easily crushed and deformed, and there was a risk that the function of the drain paper would deteriorate.

The present invention prevents deformation of the protrusions by forming the side walls of each protrusion at a substantially right angle to the water-permeable sheet, and by hanging the tips of the protrusions against the tips of both side walls of the mating groove. The purpose is to provide drain paper that can prevent functional deterioration.

The present invention will be specifically described below based on embodiments shown in the drawings.

FIG. 1 shows a drain paper according to the present invention, in which a substrate 4 has a water-permeable sheet 1 stretched on one side of a corrugated plate 2 with grooves 3, 3a alternately formed on both sides, and the water-permeable sheet 1 is placed on the outside. It is formed by folding it in half along the groove 3 so that it faces , and joining the leading edges of both grooves.

As shown in FIG. 3, the corrugated sheet 2 is formed by extrusion molding of thermoplastic resin such as polyethylene or polypropylene, and the side walls 31, 31 of each groove 3, 3a are formed at right angles to the water-permeable sheet 1. There is.

Water passage holes 6 penetrating from the front and back are provided at appropriate intervals in the tops of the respective grooves 3a on one surface of the corrugated plate 2, that is, the protrusions 5 when viewed from the other surface.

The water passage hole 6 is an elongated hole that is long in the direction in which the drain paper is driven, that is, in the direction of the protrusion 5, so that the strength of driving the drain paper does not decrease even if the hole area is increased.

Further, positioning pieces 52, 52 are provided on the tip end surface of the protruding strip 5 in parallel and protruding over the entire length of the corrugated plate 2, corresponding to the width of the groove strip.

The water-permeable sheet 1 is made of a material with good water permeability, such as non-woven fabric, and is adhered to the corrugated plate 2 so as to close the opening surface of the groove 3a in which the water passage holes 6 are formed.

Fold the substrate 4 in half with the water-permeable sheet 1 facing outward, and make the grooves 3 and the mating protrusions 5 face each other,
Both ends of the substrate 4 are bonded 11.

When the drain paper is placed in the soil, as shown in FIG.
1 and 31 are abutted against each other, and the positioning pieces 52 and 52 of the protrusion 5 are fitted into the groove 3, so that a water passage 7 is formed between the protrusion 5 and the groove 3.

Water that has permeated the water-permeable sheet 1 and entered the grooves 3a flows into the water passage 7 through the water passage holes 6 of the groove 3a, and rises in the water passage 7 by capillary action.

Even if the water-permeable sheet 1 is damaged or the grooves 3a are narrowed, the water passage 7 formed between the overlapping corrugated plates 2, 2
The capillary action of is not impaired and the function as drain paper is not lost.

However, the side walls 31, 31 of the groove 3 and the side wall 3
Side walls 51, 5 of the protrusion 5 butted against 1, 31
1 is formed at right angles to the water-permeable sheet 1, so it can withstand large pressure and is difficult to deform.
2 and 52 are fitted into the mating groove 3, so the protrusion 5
Therefore, no displacement of the opposing groove 3 occurs.

As described above, in the present invention, when the corrugated sheets 2 are overlapped, the water passage 7 is formed between the corrugated sheets 2, 2, and water flows into the water passage 7 through the water passage hole 6 formed in the corrugated sheet 2, forming a capillary tube. Since water can be absorbed by the action, even if the water-permeable sheet 1 is damaged or the grooves 3a are narrowed, it will not lose its function as a drain paper.

Further, the side walls 51, 51, 31, 31 of the protrusion 5 and the groove 3 facing the protrusion 5 are covered with the water-permeable sheet 1.
Since it is formed perpendicularly to the ground pressure, that is, in the direction in which ground pressure is applied, it has a large pressure resistance, is not easily crushed, and can prevent the drain paper from deteriorating in function.

In the case of the above embodiment, one substrate 4 was folded in half to form the drain paper, but the invention is not limited to this, and it is also possible to overlap two substrates with the water-permeable sheets 1, 1 on the outside. stomach.

FIG. 4 shows another embodiment of the positioning piece 52 formed on the distal end surface of the protrusion 5, in which the distal end surface of the protrusion 5 is made to protrude like a mountain over the entire length so that the center part is higher. A positioning piece 52 that fits into the groove 3 is formed, and a water passage hole 6 is opened at the top.

Further, it has excellent effects such as being easily formed by folding the substrate 4 in half or by stacking two substrates.

It should be noted that the present invention is not limited to the above-mentioned configuration, and it goes without saying that various modifications can be made within the technical scope described in the claims of the utility model registration.

[Brief explanation of drawings]

Fig. 1 is an oblique view of the drain paper, Fig. 2 is a sectional view of the used state, Fig. 3 is an oblique view of the corrugated plate, Fig. 4 is a sectional view of another embodiment, and Fig. 5 is a A sectional view of the proposed drain paper, and FIG. 6 is a perspective view of a conventional example. 3... Grooves, 5... Projections, 31, 31, 51,
51...Side wall, 52...Positioning piece.

Claims (1)

[Claims for Utility Model Registration] A corrugated plate 2 has parallel grooves 3 and 3a alternately formed on both sides, and the openings of the grooves 3a on one side of the corrugated plate 2 are covered with a water-permeable sheet 1, and the openings are closed. Grooves 3a
Fold the substrate 4 in half along the groove 3 with the water-permeable sheet 1 on the outside, or fold the two substrates 4, 4 with the water-permeable sheets 1, 1 on the outside. The protrusions 5 between the mating grooves 3 and 3 are made to face each other, and the side walls 51, 51 of the protrusions 5, 5 are formed approximately at right angles to the water-permeable sheet 1, and each protrusion is Both side edges of the tip surface of the strip are butted against the tips of both side walls 31, 31 of the mating groove strip 3, and the tip surface of each protruding strip 5 is attached to the mating groove strip 3.
A drain paper characterized by having a protruding positioning piece 52 that fits and engages with the drain paper. The drain paper according to claim 1, wherein the water passage holes 6 are elongated holes extending in the direction along the grooves 3. The drain paper according to claim 1 or 2, wherein the positioning pieces 52 are provided in a parallel protruding manner with an interval corresponding to the width of the groove 3. The drain paper according to claim 1 or 2, wherein the positioning piece 52 is formed by bulging the tip end face of the protrusion 5 into a mountain shape.