JPS59145813A - Grooved culvert drain pipe - Google Patents

Abstract

PURPOSE:To obtain a culvert drain pipe having a high flexibility and a high pressure resistance by spirally winding a hollow bar-like strand around the outside of film-like strands set at an interval in parallel with the longitudinal direction. CONSTITUTION:A hollow bar-like strand 3 of a synthetic resin is spirally wound around the outside of a synthetic resin filmy strands 2 set at intervals in parallel with the longitudinal direction. Of the filmy strands 2, at least one strand 2a has a wide width enough to close 1/4-1/2 of the inside circumference of the hollow bar-like strand 3. When using such a culvert drain pipe 1, the wide filmy strand 2a is set on the downside, a filter 4 of a nonwoven fabric, perforated sheet, etc., is wound around the pipe 1, and the pipe 1 is buried under the ground.

Description

[Detailed Description of the Invention] The present invention provides j! I! Regarding synthetic resin grooved culvert drainage pipes to be installed.

Many synthetic resin pipes have been proposed as culvert drainage pipes, and this type of culvert drainage pipe has a large number of openings on the surface of the pipe to drain rainwater and spring water. Depending on the usage situation, well-balanced quality characteristics such as pressure resistance, water absorption rate, roughness coefficient, flexibility, etc. are required.

In conventional synthetic resin underdrain drainage pipes, a large number of thread-like strands extending in the longitudinal direction of the pipe form a cylindrical shape, and inside these thread-like strands are wound in a spiral shape, and these strands are integrated. One that has a mesh-like cylindrical body is known. however,
Such known underdrain drainage pipes have good water absorption (although they have a large roughness coefficient and therefore poor water flow characteristics), and also have the drawbacks of insufficient pressure resistance and poor flexibility.

Also known is a structure in which ring-shaped strands are arranged in a cylindrical shape at regular intervals in the longitudinal direction and connected by several film-shaped strands to form an integrated structure. However, although such known underdrain drainage pipes have improved roughness coefficients and flexibility, they have the drawback that the ring-shaped strands tend to break when subjected to external force and do not have sufficient pressure resistance.

Therefore, an object of the present invention is to provide a grooved underground drainage pipe that is highly flexible, has high pressure resistance, and has good water flow characteristics.

According to the present invention, a plurality of film-like strands made of synthetic resin are arranged at intervals in the longitudinal direction, and a hollow rod-like strand made of synthetic resin is spirally wound on the outside of the film-like strands. At least one of the film-like strands is formed wide, that is, in the form of a groove. This wide film-like strand is therefore referred to herein as a groove.

The grooved underdrain drainage pipe according to the present invention is used by being buried in the soil in a place where the groundwater level is high, for example, in a field. As a result, a cylindrical cavity is formed in the soil, and groundwater enters the cavity in the underdrain drainage pipe through the gap between the film-like strand and the rod-like strand, and is drained through the cavity. In this case, in the present invention, since the film-like strand is formed inside the spiral rod-like strand, the inner surface is smooth and the roughness coefficient is small.
Therefore, the water flow performance is good. Moreover, since the spiral rod-shaped strand is formed hollow, it has an eave m and extremely high pressure resistance. Furthermore, since the strands arranged in the longitudinal direction are film-like, they have excellent flexibility. If the wide film-like strand is buried with the wide film-like strand on the lower side, the groundwater that has entered the underdrain drainage pipe will flow on the upper surface of the wide film-like strand, resulting in better water flow performance. In addition, in sandy soil, etc.
By burying the wide culvert drainage pipe with the top side facing upward, it is possible to prevent the upper earth and sand from falling and accumulating inside the culvert drainage pipe.

In carrying out the present invention, it is preferable that the full or wide film-like strand has a width that covers 1/4 to 1/2 of the inner circumference of the rod-like strand. 1/1 of the inner circumference of the rod-shaped strand
If it is less than 4, the above-mentioned improvement in water flow characteristics and prevention of falling of earth and sand will be less effective, and the water absorbency will deteriorate as it exceeds 1/2 of the inner circumference of the rod-shaped strand.

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, an underdrain drainage pipe 1 according to the present invention includes a plurality of film-like strands 2 arranged parallel to each other at intervals in the longitudinal direction, and a plurality of film-like strands 2 arranged on the outside of the film-like strands 2. It is composed of a film-like strand 2 and two rod-like strands 3.3 that are helically wound and integrally fixed. Film strand 2
One of the strands 2a is formed like a wide groove, and extends from 1/4 to 1/2 of the inner circumference of the rod-shaped strands 1 to 3.3.
is blocking the The appropriate width of the other film-like strands 2 is about 3 to 30 mm. Further, the thickness of each film-like strand 2 is preferably about 0.3 to 1.5 mm for a pipe with a diameter of 50 mm, for example. The hollow rod-like strand 3.3 is wound in a spiral, and the inclination angle α of the spiral with respect to the axial direction is preferably 70 to 87 degrees. Therefore, for example, in a pipe with a diameter of 50 mm, the pitch D of the hollow rod-like strand 3 is Appropriately, it is about 20 to 40 mm.

Such an underdrain drainage pipe 1 is produced by simultaneously extruding a synthetic resin from an extruder having an extrusion nozzle for a fixed film-like strand 2 and an extrusion nozzle for a hollow rod-like strand 3.3 that rotates relative to the extrusion nozzle. It can be easily formed by welding a hollow rod-shaped strand 3.3 to the outer periphery of the shaped strand 2.

When using this culvert drainage pipe 1, for example, as shown in FIG.
A is placed on the lower side, and a non-woven fabric is placed around the outer periphery of the underdrain drainage pipe 1.
A filter 4 such as a perforated sheet may be wrapped and buried in the soil. As a result, groundwater passes through the filter 4 and further enters the underdrain drainage pipe 1 through the gap between the film-like strand 2 and the bar-like strand 3.3, and is drained through the underdrain drainage pipe 1. In this case, culvert drainage pipe 1
Since the water that has entered the soil flows over the upper surface of the wide film-like strand 2a, water is prevented from seeping into the soil again, and water flow characteristics are improved.

For example, in sandy soil, as shown in Figure 4,
A wide film-like strand 2a is placed on the upper side and buried. Thereby, earth and sand can be prevented from falling into the underdrain drainage pipe 1.

In addition, in the above embodiment, two hollow rod-shaped strands 3
．． Although the strand 3 is spirally wound, one or more rod-shaped strands 3 may be wound. Also, the cross-sectional shape of the rod-shaped strand 3 is shown in Figure 5 (a).
As shown in (E) to (E), various shapes can be used, such as square, rectangle, circle, ellipse, and trigonal shape. moreover,
The wide film-like strand 2a is connected to the underdrain drainage pipe 1.
They may be provided on the upper and lower surfaces of the.

As explained above, according to the present invention, a hollow rod-shaped strip in which a film-like strand is spirally wound! ~It is formed inside the lands, and at least one of them is wide, so the inner surface of the underdrain drainage pipe is smooth,
The 11 degree coefficient is small, thus improving water flow performance.

In addition, since the hollow rod-shaped strand is spirally wound, it is lightweight and has extremely high pressure resistance.

For example, in the case of a pipe made using high-density polyethylene with a density of 200 (]
It is up to 30 to 34 kc (] per unit, whereas in conventional underdrain drainage pipes, it is 10-15 kc+ per 10 cm.

In this way, it is possible to make a hollow rod-like strand thicker by thinning the film-like strand, which has a high structural pressure-resistant strength and has relatively little effect on the strength, and using the corresponding amount of material, so the pressure-resistant strength can be increased. Material costs can be reduced while maintaining sufficient retention. Further, the rod-shaped land 1 to the land that is spirally turned has an inclination angle of, for example, 70 to 87 degrees, so that it is difficult to break even when subjected to external force.

Furthermore, since the strands formed in the longitudinal direction are film-like, they have excellent flexibility.

By arranging a wide film-like strand on the lower side, the water flow characteristics are further improved, and it can also be used as a water collection pipe in areas where the underground water level is random, long routes, slopes, etc. It can also be used in sandy soils by placing a wide film-like strand on top.

[Brief explanation of drawings]

FIG. 1 is a side view of a grooved culvert drainage pipe showing an embodiment of the present invention, FIG. 2 is a side sectional view of the grooved culvert drainage pipe, and FIG.
Figures 4 and 4 are cross-sectional views showing examples of the use of grooved culvert drainage pipes, and Figures 5 (a), (b), (c), (d), and (e).
FIG. 2 is a cross-sectional view showing the shape of a hollow rod-like strand. 1... Underdrain drainage pipe 2... Film-like strand 2a... Wide film-like strand (vortex)
3...Hollow rod-shaped strand Figure 3 Figure 4 Figure 5 (A) (0) (C) (D) (Thursday)
Big picture ◎mouth Δ

Claims (2)

[Claims] (1) Consisting of a plurality of film-like strands made of synthetic resin arranged parallel to each other at intervals in the longitudinal direction, and hollow rod-like strands made of synthetic resin spirally wound around the outside of the film-like strands. , a groove corner culvert 41F water pipe, characterized in that one of the lower ends of the film-like strand is formed wide. (2) The groove-angle culvert drainage pipe according to claim 1, wherein the wide film-like strand has a width that covers 1/4 to 1/2 of the inner circumference of the rod-like strand.