JP2528673B2 - Synthetic resin core material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is suitable as a core material such as a synthetic resin core material, particularly a planar drainage material for guiding water in the ground to a gutter or the like for drainage. The present invention relates to a synthetic resin core material that can be used for.

[Prior art] A planar drainage material used as backfill drainage material for tunnels, glands, slopes, etc. forms a water passage inside the ground, and the water in the surrounding ground collected in the water passage forms a gutter. It has a role of draining by guiding to other places, and conventionally, various planar drainage materials having a synthetic resin core material have been proposed.

For example, the core material of the sheet drainage material disclosed in Japanese Utility Model Publication No. 62-20499 is made of a synthetic resin sheet, and a large number of ridges and valleys are formed by molding the sheet into an uneven shape. Having a shaped portion, the gap spaces formed between the respective mountain shaped portions and between the respective valley shaped portions, and a large number of through holes formed in the aforementioned mountain shaped portion and the valley shaped portion are used as water passages. I can do it.

In addition, instead of the above sheet, there is also one in which a net made of synthetic resin is formed in an uneven shape.

[Problems to be Solved by the Invention] However, as in the core material disclosed in the above publication, the sheet is formed at the forming points of the respective peak-shaped portions and valley-shaped portions by molding the sheet in a concavo-convex shape. Of the resin layer forming the ridges and valleys is weakened, and the thickness direction of the core material (the height direction of the ridges or the valleys is reduced). It is easy to cause inconveniences such as deformation and crushing due to load such as earth pressure acting in the depth direction of the shape part, and if such inconvenience occurs, the width of the water passage will become uneven in each part There is a problem that a sufficiently wide water passage is not secured and drainage performance is impaired. In addition, since the stretched synthetic resin is apt to cause heat shrinkage, the core material disclosed in the above publication has a problem that the water passage is narrowed due to heat shrinkage for some reason.

The core material formed by molding the net made of synthetic resin in an uneven shape is difficult to position the crossing point of the warp or weft of the above net at the top of the mountain-shaped portion or the bottom of the valley-shaped portion because of problems in molding technology. In most cases, only the warp threads and the weft threads of the net pass through the top or bottom, and the intersections of the warp threads and the weft threads are not located. Therefore, the pressure resistance of the top and bottom is extremely reduced, and the above problem becomes more remarkable.

The present invention has been made in view of the above problems, and the mountain-shaped portion and the valley-shaped portion are constituted by a plurality of synthetic resin ribs that are not stretched, and the intersections of the plurality of ribs are the peaks and valleys of the mountain-shaped portion. Providing a core material made of synthetic resin that is positioned at the bottom of the shaped part to prevent it from deforming or being crushed by the load such as earth pressure, and that secures a sufficiently wide space between the ribs The purpose is to do.

[Means for solving problems]

In order to achieve the above object, the synthetic resin core material of the present invention is such that the tops of a large number of chevron portions and the bottoms of a large number of trough portions are arranged in a regulated manner in plan view, and the tops of the chevron portions and their chevron shapes are formed. The bottoms of the valley portions adjacent to each other around the portion, and the bottom of the valley portion and the tops of the adjacent chevron portions around the valley portion are integrally connected by a plurality of spaced ribs. The plurality of ribs are composed of a synthetic resin molded product that is not stretched.

[Action]

The load in the thickness direction acting on the core member having the above structure is supported by a plurality of unstretched ribs connecting the top of the chevron portion and the bottom of the trough portion. Further, since the rib is a synthetic resin molded product that is not stretched and the intersections of the ribs are located at the top and bottom, a very large strength is secured. Further, since the core material is a three-dimensional structure including a plurality of ribs, a wide space portion secured inside the core material can be used as, for example, a water passage for a planar drainage material, and the core material as a whole has an appropriate flexibility. Have.

〔Example〕

FIG. 1 is a vertical sectional side view in which a part of a core material 1 according to an embodiment of the present invention is cut away, FIG. 2 is a partial plan view, and FIG. 3 is a schematic perspective view of a main part. As shown in these drawings, in the core material 1, a large number of peak-shaped portions a and valley-shaped bottom portions b are alternately arranged in a rectangular lattice pattern in plan view, and the peak portions a and The bottoms b of four valley-shaped portions adjacent to each other around the mountain-shaped portion are integrally connected by four ribs 2 at equal intervals. These ribs 2 are common to the ribs that integrally connect the bottom portion b of the valley-shaped portion and the top portions a of the plurality of mountain-shaped portions adjacent to each other around the valley-shaped portion. Rib 2
Is an elongated strip having a rectangular cross section in which only the portions in the vicinity of the top portion a and the bottom portion b are curved in an arc shape, and the other portions are linear, and the width dimension H is larger than the thickness dimension T thereof. It is shaped like a plate. Moreover, the rib 2 is formed by injection molding a synthetic resin, for example, a thermoplastic resin such as polyvinyl chloride resin or polypropylene resin, into the above-described shape, and is formed by drawing a warp or a weft of a synthetic resin net. Not a thing. In the above description, the chevron portion means a portion that is raised in a chevron shape around the top portion a, and the trough portion is a portion that is recessed in a trough shape around the bottom portion.

Such a core material 1 forms a groove-shaped molding surface for molding the ribs 2 on each of a pair of mating dies, closes the dies, and presses a synthetic resin into the molding surface to perform molding. It is molded in the form of a three-dimensional structure by releasing the mold later. Therefore, the core material of the present invention can be manufactured by one-time molding, and it is necessary to mold the sheet or net once with a synthetic resin as in the conventional method and then mold them into an uneven shape twice. In comparison, the molding process is simplified and the cost is low.

The core 1 has a top portion a of a mountain portion and a bottom portion b of a valley portion.
That the four ribs 2 ... cross each other, and those ribs 2
The adjacent widths of the ... Are orthogonal to each other, and the ribs 2 are not stretched so that they have a uniform thickness T in the entire length portion, etc. Therefore, it has a very large compressive strength in the thickness direction. Therefore, when it is used as a core material for a planar drainage material, it can sufficiently resist earth pressure, and the ridges and valleys are unlikely to be deformed or crushed.
Moreover, the core material 1 has a three-dimensional structure with the ribs 2 ... And a wide space between the ribs 2 ... serves as a water passage, so that a high drainage capacity is provided for a long period of time. Nevertheless, since the core material 1 as a whole has flexibility, if the core material 1 is used as a core material for a planar drainage material,
Familiar with unevenness in the ground, water collection capacity is improved. Also,
As shown by the phantom lines in FIG. 3, if protrusions 6 and 7 of a predetermined length are respectively provided on the back surface of the top a of the mountain portion and the top surface of the bottom b of the valley portion, the mountain portion and Even if the valley portion is crushed by earth pressure, it is possible to prevent the above-mentioned protruding parts 6 and 7 from functioning as spacers and completely eliminating the above-mentioned space portion. However, there is an advantage that the minimum level is secured.

In order to use the core material 1 as a core material for a planar drainage material,
As shown in FIG. 7, when the core material 1 is covered with the outer skin 3 made of a water-permeable woven fabric, non-woven fabric, knitted fabric, papermaking, etc., the mud does not enter the space portion of the core material 1 when buried in the ground. Keep it. In such a case, when the outer cover 3 is pushed into the inside of the mountain-shaped portion or the inside of the valley-shaped portion of the core material 1 by the earth pressure, the above-mentioned space portion becomes narrow and the drainage performance is impaired. In order to control this, it is effective to integrally project the protrusions 4 and 5 on the top portion a of the mountain portion and the bottom portion b of the valley portion as shown in FIG. If you do this, the protrusions 4 and 5 will be the outer skin 3.
It is difficult for the outer skin 3 to be pushed into the inside of the mountain portion or the inside of the valley portion due to being caught in the area, and the deterioration of the drainage performance due to the narrowing of the space portion is effectively suppressed.

The width dimension H of the rib 2 of the embodiment described above is uniform over the entire length, but the width dimension of the rib 2 is made wider at the top a of the chevron portion than at other portions as shown in FIG. 6, for example. In this case, the top portion a is locally reinforced so that the top portion a is less likely to spread due to the load, and there is an advantage that the top portion a is further strengthened against a load such as earth pressure. Therefore, with the configuration shown in FIG. 6, it is not necessary to provide an annular connecting rib or the like for connecting the ribs 2 in the vicinity of the top a to prevent the top a from expanding. The same applies to the bottom of the valley portion. Also,
The top portion a of the mountain portion in the above embodiment has a cross-shaped configuration in which four ribs 2 are assembled, but other configurations, for example, an annular ring plate 5 as shown in FIG. May be formed, or may be formed in a square annular shape or a non-annular flat plate shape. According to these, since the top portion a has a certain flatness, the load acting on the top portion a is dispersed, and the deformation resistance of the top portion a is improved. Further, the arrangement shape of the top of the mountain portion and the bottom of the valley portion is not limited to the lattice shape, and may be a triangular shape, a hexagonal shape, or any other shape.

〔The invention's effect〕

As described above, the core material of the present invention is molded in a shape of a three-dimensional structure by one molding, and the ribs forming the mountain-shaped portion and the valley-shaped portion are not stretched, so that the ribs cause thermal contraction. Of course, there is no fear that the ribs are arranged correctly and that the crossing points of the ribs are located at the top of the mountain portion and the bottom of the valley portion synergistically, and the entire core is covered. It has uniform and great strength. Therefore, when the core material of the present invention is used as the core material of the planar drainage material, it becomes difficult for the mountain-shaped portion and the valley-shaped portion to be deformed or crushed by the surrounding earth pressure, and between the plurality of ribs. The wide space part of the water serves as a water passage, and the top and bottom are arranged in a regulated manner, so that the width of the water passage is uniform in each part, and the drainage performance does not deteriorate for a long time. It becomes a surface drainage material.

In addition, since the core material as a whole has moderate flexibility, when the planar drainage material using the core material of the present invention is buried in the ground, the planar drainage material is well protected from unevenness in the ground. Familiarity and water collection capacity is improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view in which a part of a core material according to an embodiment of the present invention is cut away, FIG. 2 is a partial plan view, FIG. 3 is a schematic perspective view of a main portion, and FIG. 4 is a main portion of a modified example. FIG. 5 is a schematic perspective view showing an essential part of another modification, FIG. 6 is a schematic perspective view showing an essential part of still another modification, and FIG. It is a schematic perspective view which shows the example of use at the time of utilizing as a drainage material. 1 ... Core material, 2 ... Rib, a ... Top of mountain portion, b ... Bottom of valley portion.

Claims (1)

(57) [Claims] 1. The tops of a large number of chevron portions and the bottoms of a large number of valley portions are arranged in a restricted manner in a plan view, and the crests of the chevron portions and the bottoms of a plurality of valley portions adjacent to each other around the chevron portions are arranged. , And the bottom of the valley-shaped portion and the tops of a plurality of chevron-shaped portions adjacent to the valley-shaped portion are integrally connected by a plurality of spaced ribs, and the plurality of ribs are not stretched synthetic resin molding A core material made of synthetic resin, characterized in that it is made of a product.