JPH0226980Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a blind drainage material for civil engineering that is used for underground drainage at the boundary between cutting and filling, the backfilling of structures, etc.

<Conventional technology> Conventionally used groundwater drainage, such as drainage from cutting and embankment boundaries, subgrade drainage, slope drainage, drainage of water flooded in the backfill of structures, etc., commonly used in construction work. Drainage means include buried earthen pipes or perforated pipes. In this case, when burying the earthen pipes, etc., it is necessary to dig a trench of considerable width, and it is also necessary to backfill with a highly water-permeable material, which is troublesome. Moreover, this type of drainage means requires additional facilities to be installed, which results in costly construction work. Of course, when used for a very long period of time, this can lead to clogging of pipes, etc., and the drainage effect is not achieved, which tends to reduce the strength of the embankment etc. and cause frost heaving. This is particularly troublesome when removing groundwater from natural surfaces or embankment slopes that are drained by slopes, and landslides and the like caused by underground drainage are still occurring frequently.

<Problems to be solved by the invention> In view of the above-mentioned circumstances, the present invention aims to provide a blind drainage material that serves as a simple drainage means that does not cause clogging even during long-term use.

<Means for solving the problem> In the present invention, a cylindrical bag of a predetermined length is formed from a water-permeable fabric made of coarse plain weave of synthetic resin fibers such as polypropylene, and inside the cylindrical bag, The cylindrical bag is filled with spherical foamed polystyrene particles made by foaming foamed polystyrene beads, and connecting strings with both ends extending outward are connected to symmetrical positions in the longitudinal direction of this cylindrical bag to form a cylindrical shape as a whole. This is a blind drainage material.

<Function> With the above structure, the blind drainage material that will become the bag is laid one after another in a groove dug at a predetermined location, and a protruding connecting string is tied to each end of each bag to connect the two ends. When the ends of the strings are pulled, the bags are tightly butted against each other and arranged, creating a kind of drainage channel as a whole. If the bag is backfilled in this state, groundwater will permeate through the bag and be drained blindly through the expanded polystyrene particles packed inside, which serve as a filter. Of course, since this expanded polystyrene particle layer is formed by disposing a bag serving as a woven fabric on the surface, dirt, sand, etc. do not enter the expanded polystyrene particle layer, and clogging does not occur.

<Example> Hereinafter, the present invention will be described in detail based on the drawings of the example.

Figures 1 and 2 show an embodiment in which a connecting string is arranged outside the bag, and 1 is a cylindrical bag made of polypropylene made of coarse plain weave etc. through which water can permeate. At symmetrical positions in the longitudinal direction of the cylindrical bag body 1 that is the fabric (up and down positions in the figure), string passage parts 2 with openings at both ends are provided in an overhanging manner, and connecting strings 3 are connected to the string passage parts 2, respectively. At the same time, the interior 1a of the cylindrical bag 1 is filled with foamed polystyrene particles 4 made by foaming foamed polystyrene beads with a predetermined steam heating, and a blind drainage material 5 having a cylindrical shape as a whole is formed.
becomes. In this case, the size of the cylindrical bag 1 is, for example, 10 cm to 1 m in diameter and 2 m to 8 m in length, and the expanded polystyrene particles 4 are foamed particles with a particle size of about 2 mm to 7 mm.

To explain this effect now, for example, as shown in Figure 4, when using blind drainage when constructing the roadbed of a paved road using cut and mounded earth, the connection point c between cut and mounded earth B (the sliding of the mound) is Dig a predetermined groove A in the groove A, and line up the cylindrical blind drainage materials 5 one after another in the groove A (of course, if necessary, groove A may not be provided and the blind drainage materials 5 may be (It is also possible to simply arrange them at the connection part c position.) In this case, if the connecting strings 2 guided on both sides of the bag body 1 of each blind drainage material 5 are tied to the connecting strings 2 of the adjacent bag bodies 1, the connecting strings 2 will pass through the string passage part 2 and be displaced. If the outermost connecting string 2 connecting the plurality of bags 1 in sequence is strongly tightened, the bag end surfaces 1b, 1b, which are the respective lids or bottoms of each bag 1, will come into contact with each other, and water will not leak out from each other. It becomes permeable (see FIG. 2), and the whole constitutes a kind of blind drain 5'. Of course, the bags 1 arranged vertically in a straight line can also be arranged in a somewhat curved arrangement depending on the degree of tightening of the connecting strings 2, 2 on both sides.

Here, the water that has permeated into the mound b is located at the blind drainage material 5, and since this bag body 1 has a coarse plain weave fabric that allows only water to pass through, the clogging factors such as soil and sand can cause clogging of the bag body 1. Instead of flowing into the interior, the water may be drained by a kind of filter action formed by the 4 groups of expanded polystyrene particles inside, or it may flow sequentially into an array of blind drainage materials 5 to obtain an underground waterway.

Figure 5 shows the use of slopes for single-sided cutting and single-sided construction. In this case, the blind drainage material 5 arranged in the diagonal groove A is fixed with an appropriately shaped anchor 6 so as not to cause displacement. Even in such diagonal use, only underground water permeates into the bag body 1 as described above, so it is possible to reduce the moisture content of the soil in the cut-out and mounding parts, and it does not cause landslides.

FIGS. 6 and 7 show another embodiment of the bag body, and in this case, the position of the connecting string to be inserted is arranged inside the bag body. That is, similarly to the above, a string passage part 2 is formed at a position symmetrical to the circumferential wall of the interior 1a of the polypropylene cylindrical bag 1 which is a coarse plain weave, and a connecting cord 3 is inserted into the string passage part 2.

In the case of such a blind drainage material 5, the string passage part 2
is housed in the bag body 1, so even if the width of the guide groove A is as narrow as the bag diameter, it can be easily buried. Even in the drainage action at this time, since the bag body 1 is formed with a fabric (water-permeable fabric) that allows only water to pass through, as described above, the four groups of expanded polystyrene particles packed in the bag body 1 are covered with soil. Drainage can be carried out underground on slopes without causing clogging.

<Effects of the invention> As mentioned above, the blind drainage material of the invention consists of a cylindrical bag made of water-permeable fabric made of synthetic resin such as polypropylene, filled with foamed polystyrene particles, and a connecting string attached to the bag. Because it has a structure that communicates with the polystyrene particles, it is strong and will not change (corrosion, etc.) even during long-term buried use, and since only the permeated water is guided into the expanded polystyrene particles that will be used as a filter, no clogging will occur. Moreover, since this group of bags is made into a straight line by connecting the connecting strings, it becomes possible to form a kind of underground drainage channel as a whole, which prevents the strength of the embankment from decreasing, especially on slopes. It eliminates soil layering and distortion, which in turn helps prevent frost heaving, and in the case of roads, maintains the bearing capacity of roadbeds, roadbeds, etc. Of course, it is also ideal as a backing drainage material for structures. Furthermore, the advantage of the present invention is that the bag is filled with extremely light expanded polystyrene particles, so the bag unit is light and easy to handle, which provides practical effects.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention. Fig. 1 is a partially cutaway slope view, Fig. 2 is a slope view of a plurality of particles connected, Fig. 3 is a front view of expanded polystyrene particles, and Fig. 4 is a diagram showing the use of expanded polystyrene particles. FIG. 5 is an explanatory view of the state in which the bag is used, and FIGS. 6 and 7 are a slope view and a sectional view showing other embodiments of the bag body. DESCRIPTION OF SYMBOLS 1... Cylindrical bag body, 2... String passing part, 3... Connecting string, 4... Foamed polystyrene particles.

Claims (1)

[Scope of utility model registration request] A blind drainage material comprising a synthetic resin cylindrical bag made of water-permeable fabric such as coarse plain weave, filled with expanded polystyrene particles, and connected with connecting strings at symmetrical positions in the longitudinal direction of the bag.