JPH05202512A - Construction of underdrain tube - Google Patents

Abstract

PURPOSE:To enhance the construction workability of underdrain tube by a method in which in the formation of a culvert for draining under damp ground, a bullet is attached to the tip of a corrugated tube wound around a turntable, set to a given depth in a trench formed in the initial end of the culvert, and dragged. CONSTITUTION:A trench 2 is excavated on downstream side of sludgy ground, damp ground, or wet farm ground 3, and a corrugated tube 1 of synthetic resin is placed on a turntable 4 and set near the trench 2. A bullet 12 is attached to the tip of the tube 1 and set to a given depth in the trench 2. The bullet 2 is connected through a shunk 11 to a dragger 10 and the tube 1 is dragged to a given position to form a culvert 20. Water in the ground is collected from many small holes of the tube 1 and drained from the tube end on the downstream side. Even the corrugated tubes can thus be smoothly set, the breakage and deformation of the tube 1 can be prevented, and the weight of the device can be reduced. Strength against soil pressure can be raised and draining function can be maintained for a long period of time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction method in which a bullet is pulled by a towing machine to provide an underdrain.

[0002]

2. Description of the Related Art Conventionally, there are various methods for constructing a bullet culvert. For example, a method in which only a bullet is run into the ground to provide a culvert, a method in which a smooth pipe is buried after traveling a bullet, a method in which a belt-like sheet is formed in a cylinder to form a culvert, or a pipe is mounted on a towing machine There was a method of continuously laying a pipe just behind the bullet.

[0003]

Since the construction method using a bullet culvert is basically a method of running a bullet to form a culvert, it is better than a method in which a trencher or the like forms a groove to bury a corrugated pipe. And there is a big feature that the construction speed is extremely fast. However, for example, a so-called mogura culvert without a pipe buried therein has a drawback that the culvert is easily buried.

The method using a smooth tube has a tube diameter of 5
When the length is 0 mm or more, it is difficult to wind and a long object cannot be used. Therefore, a relatively thin pipe is buried, which causes a problem that sufficient drainage cannot be performed. Further, if the wall thickness of the pipe is made thin, the pipe becomes light in weight, the flexibility of the entire pipe is generated, and winding is possible, but there is a problem that the pipe is destroyed because the earth pressure resistance strength becomes small.

Further, the one in which the strip-shaped sheet is formed in the cylindrical body to form the underdrain has a small earth pressure resistance as in the above,
There was a problem that the cylinder was easily destroyed.

Further, the method of laying the pipe by placing it on a traction machine has a problem that the pipe is often cut because the pipe can be bent at a substantially right angle.

[0007] These conventional underdrain generally have a smooth outer shape in order to reduce the resistance to the soil as much as possible when the tube is pulled behind the bullet. This is because it is important to avoid troubles in construction and construction speed, and it can be said that the size of the pipe and the strength of the pipe against earth pressure have been mostly sacrificed in the past.

The present invention has been made in view of the above problems, and has a pipe diameter large enough as an underdrain drainage pipe,
Moreover, it is an object of the present invention to provide a construction method capable of constructing a corrugated pipe having a high earth pressure resistance strength with a bullet culvert.

[0009]

In order to achieve the above object, a method of constructing an underdrain drainage pipe according to the present invention is to first form a groove for introducing a corrugated pipe, and to form a corrugated pipe wound behind the groove. A turntable is placed, one end of the corrugated pipe is detachably attached to the rear of the bullet pulled by the towing machine, and the towing machine is run to pull the corrugated pipe into the ground. is there.

[0010]

According to the present invention, since the groove for introducing the corrugated pipe is formed and the corrugated pipe is on the turntable,
When the pipe end is attached to the back of the bullet and is pulled into the ground, the irregularities on the outer surface of the corrugated pipe have almost no resistance, and the corrugated pipe is pulled out while the turntable rotates, so the pipe is strongly pulled. The tube is not torn and the connection between the bullet and the tube is not broken because it is not in a state.

Further, since the turntable on which the corrugated pipe is placed can be fed out simply by placing it in the rear of the introduction groove, there is an advantage that no labor is required for construction. Further, by using a corrugated pipe, it can be wound even if the pipe diameter is 50 mm or more, and it is lightweight and has high earth pressure resistance.

[0012]

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

FIG. 1 is an explanatory view showing an embodiment of the construction method of the present invention, in which 1 is a corrugated pipe made of synthetic resin. As the corrugated tube 1, a tube having annular peaks and valleys alternately, or a tube in which peaks and valleys are spiral is used. Since these pipes have thin ridges and valleys, they are flexible and can be easily wound. What is used as a pipe for underdrain drainage has an inner diameter of about 50 to 100 m.
m, outer diameter is about 60-120 mm, length is about 30
Those of m to 100 m are preferably used. Also, many small holes are bored in the valleys of these pipes, and the open area ratio is 3
%, The water absorption is about 85 to 90%. The material of the tube is a thermoplastic resin such as polyvinyl chloride or high density polyethylene. Such a long tube 1
Is transported to the construction site as a scroll.

In the construction method of the present invention, first, a groove 2 is dug in a downstream side of a mud, a wetland or a moist field (hereinafter referred to as a field) 3 so that a drainage pipe can be buried. The bullet 12 for forming the underdrain 20 at the tip of the shank 11 mounted on the towing machine 10 and the auxiliary bullet 1
3 is attached, and the corrugated tube 1 is firmly and detachably connected to the rear of the auxiliary bullet by a connecting tool 14, and the groove 2
To the predetermined position in the field 3 or the like. At this time, the corrugated tube 1 is placed on the turntable 4, and when the end of the tube 1 is pulled, the turntable 4 rotates and the tube 1 is delivered with almost no resistance. Here, the position of the turntable 4 is preferably near the groove 2 and behind the traction machine 10 traveling. Since the outer surface of the corrugated tube 1 has an uneven shape, when it comes into strong contact with earth and sand or the like, a large resistance is exerted. Be careful as the connecting part may come off. Therefore, it is important to position the turntable 4 at a position where the tube 1 is smoothly introduced into the underdrain 20.

FIG. 2 is a perspective view showing an example of the turntable. In FIG. 2, the turntable 4 is provided with a pedestal 15 below, and four leg portions 16 are provided under the pedestal 15 for placing the pedestal 15 in a stable state. By the support of the leg portions 16, it is possible to install even on uneven ground without tilting or rolling. There is a rotating shaft (not shown) at the center of the pedestal 15,
There is a turntable 17 above it. Four support rods 14 are erected in the vicinity of the center of the turntable 17, and the support rods 14 are inserted into the center of the wound corrugated pipe.

As the towing machine 10, a civil engineering vehicle such as a bulldozer or an agricultural vehicle such as a cultivator is preferably used.

Further, the corrugated pipe 1 used as the underdrain drainage pipe may be filled with a water-permeable material such as chaff, around the corrugated pipe 1.
In places with good soil quality, sufficient drainage is performed without the use of permeable materials. The underdrain drainage pipe according to the present invention has a depth of less than 1 m, and is generally horizontal or is gradually shallow toward the direction of the towing machine 10 so that the downstream side becomes low, and the propelling of the bullet is performed in consideration of the flow gradient of the drainage pipe. It is desirable to do. Also, the corrugated tube 1
When is installed in the underdrain 20, it is preferable to install a rising pipe (not shown) at the upstream end so that maintenance can be performed at a later date. The downstream end of the pipe 1 is connected to a drain pipe such as a non-perforated pipe by using a joint.

[0018]

As is clear from the above description, the construction method of the underdrain drainage pipe of the present invention is to construct by the bullet underdrain construction method using a long corrugated pipe whose surface is uneven. A turntable is placed behind the dug groove, and a corrugated pipe is guided from there to a culvert formed by bullets. Even with a corrugated pipe, the pipe can be laid smoothly and continuously with almost no resistance. Therefore, there is a remarkable effect that the pipe can be installed quickly and without trouble, without being cut or deformed. Further, since it is a corrugated pipe, it is lightweight, has a high earth pressure resistance, and has the effect of exhibiting a drainage function for a long period of time.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of a construction method of the present invention.

FIG. 2 is a perspective view of the turntable used in FIG.

[Explanation of symbols]

 1 Corrugated tube 4 Turntable 10 Traction machine 12 Bullet 13 Auxiliary bullet

Claims (1)

[Claims] 1. A groove for introducing a corrugated tube is formed, and a turntable on which a corrugated tube is wound is placed behind the groove, and one end of the corrugated tube is placed behind a bullet pulled by a towing machine. A method of constructing an underdrain drainage pipe, characterized in that the corrugated pipe, which is removably attached to and is pulled by a towing machine, is pulled into the ground.