JPS6117055Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a novel mesh system that can be used in conjunction with conventional underdrain drainage pipes and can efficiently guide underground water stagnant on both sides of the underdrain pipes to the underdrain drainage pipes. Regarding underdrain members.

Generally, the construction of an underdrain involves digging a trench 100 from the ground as shown in Fig. 6, installing an underdrain drainage pipe 101 having a water absorption hole at the bottom of the trench at a slope, and then using a water-conducting material 102 such as rice husk or ballast. Ditch 10 with soil 103
This is done by filling in 0's. However, in a culvert with such a structure, the water-permeable material 102
In the buried area a, the water absorbed into the ground is efficiently guided to the underdrain drain pipe 101 through the gap in the ballast 102, resulting in better drainage. There was a problem that drainage was not very good because most of the water was not guided to the underdrain pipe 101 and remained underground.

In view of the above-mentioned problems, the present invention has been made to provide a net-like underdrain member that can quickly guide underground water absorbed and stagnant from areas on both sides with poor drainage to the underdrain drainage pipe, This made it possible to construct an underdrain with almost uniform drainage performance over a wide area.

Hereinafter, the present invention will be described in detail with reference to the drawings.

That is, the net-like underdrain member of the present invention has one or both of the warp and weft of the net in the shape of a pipe, and a large number of water absorption holes are formed in the peripheral wall thereof. , Figures 1 and 5
Examples are shown in the figure.

The net-like underdrain member shown in Fig. 1 has a mesh having a rectangular mesh 1, and only the warp threads 2 are pipe-shaped, and a large number of water absorption holes 3 are randomly formed on the peripheral wall of the pipe-like warp threads 2, and thin weft threads 4 and the pipe-shaped warp 2 are not knitted together, but are integrally formed of the same material, as shown in FIG. Such a net-like underdrain member can be manufactured, for example, by applying a molding technique for a non-woven synthetic resin net.

There are no particular restrictions on the thickness (outer diameter) of the pipe-shaped warp 2 or the thickness of its peripheral wall, but when manufacturing it from synthetic resin by applying the above-mentioned molding technology for synthetic resin non-woven nets. From the viewpoint of formability and compressive strength, it is desirable that the thickness of the pipe-shaped warp 2 be about 5 cm or less and the thickness of the peripheral wall be about 0.2 to 1.0 mm. Furthermore, if the distance between the warp yarns 2 is too wide, the amount of water absorption will decrease, so it is preferable to set the distance between the warp threads 2 to be 30 cm or less, preferably about 3 to 20 cm. In addition, water absorption hole 3
The size of the pipe-shaped warp 2 may be sufficient as long as it can prevent the entry of dirt particles into the pipe-shaped warp 2, but in order to exhibit good water absorption performance within a range that does not impair the strength of the pipe-shaped warp 2, the size of the pipe It is desirable to form the water absorption holes 3 with a distribution density such that the open area ratio of the shaped warp threads 2 is 3 to 15%.

On the other hand, it is desirable that the thickness of the weft yarn 4 be approximately 0.1 to 1.0 mm so that it can be easily bent. If the weft threads 4 are easily bent in this way, it is possible to wind the net-like underdrain member with the warp threads 2 in the axial direction, making it easier to transport and carry. Further, in this embodiment, a large number of weft threads 4 are provided with small intervals between them, but since they serve to connect the warp threads 2 inseparably, in the worst case, both ends of the warp threads 2 It is only necessary to provide two wires in total, one for each.

To explain the underdrain construction method that uses the above-mentioned mesh underdrain members in combination with conventional underdrain drainage pipes, the third
~4 As shown in Figure 4, first, a wide groove 5 is cut from the ground.
is dug, and an underdrain drain pipe 6 is laid in the deepest part of the center. Then, rope-shaped underdrain drain pipes A, A are laid at the bottom of the groove on both sides of this underdrain drain pipe 6. In that case, the rope-shaped underdrain drain pipes A, A are arranged so that the pipe-shaped warp threads 2 thereof are at right angles to the under-drain drain pipe 6, and such that the pipe-like warp threads 2 slope downward toward the under-drain drain pipe 6. Lay down. Next, the underdrain drain pipe 6 and the mesh underdrain member A
A water-permeable material 8 such as rice husk or ballast is placed on top of the trench, and soil 9 is poured on top of it to completely fill the trench 5 and complete the construction. Note that the water-permeable material 8, such as rice husk or balus, on which the net-like underdrain members A and A are placed is not necessarily required, and may be replaced with soil. Also,
It goes without saying that instead of rice husk or balas, any water permeable material such as sand or nonwoven fabric can be used as the water permeable material.

In the culvert constructed in this way, water absorbed from the buried area a of the culvert drain pipe 6 is efficiently guided to the culvert drain pipe 6 through the gaps in the water-conducting material 8.
Not only does water flow into the pipe through the water absorption hole 10 of the drain pipe 6 and is drained, but also water absorbed from areas b, b on both sides where the mesh underdrain members A, A are buried is also absorbed into the mesh underdrain members A, A. It flows into the warp threads 2, 2 through the water absorption holes 3, 3 of the pipe-shaped warp threads 2, 2, and is efficiently guided to the underdrain drainage pipe 6, and the water absorption holes 10 of the drainage pipe
Since the water flows into the pipe and is drained, sufficient drainage can be achieved over a wide range of area a and area b.

Furthermore, since the net-like underdrain members A and A are net-like, they can be laid easily over a wide area at equal intervals, and because they are net-like, even if there are some irregularities on the bottom of the groove, individual pipes can be laid easily. has the advantage of having a nearly constant drainage gradient.

The net-like underdrain member illustrated in FIG. 5 has a net structure in which warp threads 2' and weft threads 4' are overlapped in a crosswise manner, and both warp threads 2' and weft threads 4' are configured in a pipe shape, and these pipe-shaped warp threads 2' and weft threads A large number of water absorption holes 3' are formed in the circumferential wall of 4'. In such a mesh underdrain member, both the warp threads 2' and the weft threads 4' are diagonal to the underdrain drainage pipe.
It is constructed in the same manner as the net-like culvert member shown in FIG. 1 above, except that it is buried at a 45-degree angle.

As explained above, the reticulated underdrain member of the present invention is
It is buried on both sides of the culvert drainage pipe, and can efficiently guide water absorbed from areas b and b on both sides, which conventionally had poor drainage, to the culvert drainage pipe, and therefore has good drainage over a wide area. This method has the remarkable effect of making it possible to easily construct an underdrain with good drainage performance.

[Brief explanation of the drawing]

Fig. 1 is a plan view of an embodiment of the present invention, Fig. 2 is a sectional view taken along the line - - of Fig. 1, Fig. 3 is a perspective view showing an intermediate stage of constructing a culvert using the same embodiment, and Fig. Figure 4 is an explanatory diagram of a culvert constructed using the same embodiment, Figure 5 is a perspective view of another embodiment of the present invention, and Figure 6 is a perspective view of another embodiment of the present invention.
The figure is an explanatory diagram of a conventional culvert. Explanation of main symbols in the drawing, 2, 2'... Pipe-shaped warp, 3, 3'... Water absorption hole, 4... Weft, 4'...
...Pipe-shaped weft, 5...Groove, 6...Drainage pipe, 8...Water passage material, A...Net-like culvert member.

Claims (1)

[Scope of utility model registration request] A net-like underdrain member in which one of the warp and weft of the net is formed into a pipe shape, and a large number of water absorption holes are formed in the peripheral wall of the pipe.