JP2017095894A - Drainage material installation method for natural ground - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drainage material installation method for natural ground, which does not damage the following filter even in the case of a drainage material having an outer periphery provided with the filter for preventing inflow of sediment, and which enables execution of work for installation of the drainage material without any vibration or noise and without earth removal.SOLUTION: In a drainage material 5, an outer periphery of a synthetic resin drain pipe 6 having a large number of water-permeable holes formed in its peripheral wall is covered with a nonwoven fabric filter 7, and its top surface is held by a geotextile net 8. A sharp-edged excavation head 9 is installed. The drainage material 5 is advanced into natural ground while the excavation head is rotated by a rotating shaft 10 for excavation, which is inserted into the drainage material 5.SELECTED DRAWING: Figure 1

Description

  This invention relates to the drainage material installation method of the natural ground which installs a drainage material in order to prevent a landslide collapse and a retaining wall collapse.

  Currently, in Japan, there is a tendency for “very heavy rain” that causes precipitation to exceed 50 mm per hour in relation to climate change, and as a result, the number of landslide disasters also tends to increase. Such climate change is also observed in snowfall areas, and landslide disasters tend to increase during the snowmelt season.

  At the time of large-scale earthquakes in recent years, major damage such as embankment collapse has occurred in embankments crossing valleys and valley filling areas in large-scale land development, and it is known that groundwater is involved in these collapses . Since the collapse of earth structures and slopes also causes damage to roads, houses, etc. that are close to them, the scale of damage tends to increase.

  An increase in groundwater level due to rainfall or melting snow reduces the stability of embankment slopes and slopes. For this reason, it is stipulated that the drainage is to be maintained, but the embankment before the legislation may not have the drainage, or even if the drainage is in place, the function may be degraded. This is one of the causes of disasters.

  In addition, it has been pointed out that the retention of groundwater in the embankment for a long period of time causes deterioration of the embankment material and may promote a decrease in the stability of the embankment during an earthquake or heavy rain.

  In order to quickly drain rainfall and snowmelt water from the embankments and slopes, measures have been taken to insert drainage pipes on slopes and slopes. However, these drainage pipes often suffer from functional deterioration due to blockage after construction in places where the drainage frequency changes significantly seasonally.

  However, this functional deterioration can be recovered to some extent by cleaning, and the frequency is preferably once every two to three years.

  Moreover, when a house is constructed on the upper part of the embankment like a built-up residential land, there is a concern that the embankment material will be washed away by the drainage water during the rain, thereby inducing the uneven settlement of the building.

The following Patent Document 1 is proposed as a drainage pipe and a drainage pipe manufacturing method and a drainage method for preventing landslide collapse and retaining wall collapse, and is a perforated drainage pipe, which is a peripheral surface of a pipe body. One or more non-porous parts are continuously formed along the longitudinal direction of the tube body, the tube body is covered with a water-permeable sheet, and a water-permeable filling is installed inside the tube body It is.
JP 2006-336338 A

  According to Patent Document 1, when the through-hole is large and earth or sand flows into the inside of the pipe body from the through-hole, the pipe body is covered with a water-permeable sheet that is a sheet having water permeability. Thus, water can be collected more efficiently by providing a large through hole while preventing outflow of earth and sand from the perforated portion.

  That is, only the water can be drained through the water permeable sheet by covering the pipe body with the water permeable sheet and placing the water drain pipe so that the earth and sand do not flow into the water drain pipe and flow out.

  As shown in FIG. 8, the conventional resin drainage pipe including the above-mentioned Patent Document 1 often strikes and penetrates the driving pipe, but if it has a water-permeable sheet, that is, a filter, it is damaged. Such a construction cannot be performed because of concerns. In FIG. 8, 1 is a drain pipe, 2 is a driving pipe, and 3 is a tip cap.

  It is an object of the present invention to drain a natural ground that can be installed without any vibration, noise, and drainage without damaging the filter even if it has a filter for preventing sediment inflow on the outer periphery. It is to provide a material installation method.

  In order to achieve the above object, according to the present invention, the drainage material is formed by covering the outer periphery of a synthetic resin drainage pipe having a large number of water permeable holes formed on the peripheral wall thereof with a non-woven fabric filter and pressing it from above with a geotextile net. The point is to install a pointed excavation head at the head of the drainage material and dig the drainage material into the ground while rotating the excavation head with the excavation rotating shaft inserted into the drainage material. is there.

  According to the first aspect of the present invention, since the drainage material is installed while excavating with the pointed excavation head installed at the head of the drainage material, the drainage material can be installed without difficulty compared to the blow. And since the drainage material made from the synthetic resin drainage pipe which comprises this is a perforated pipe | tube material by which many water-permeable holes were formed in the surrounding wall, and the inside and outside were connected, water can be taken in here. And it is possible to block the earth and sand from flowing into the water permeable holes by the nonwoven fabric filter covering the water permeable holes.

  In addition, when the water permeable filter is arranged on the outer peripheral side, the water permeable filter may be in direct contact with soil, sand, etc., but it is protected by pressing it with a geotextile net, and the water permeable filter may be damaged. Can be effectively prevented.

  According to the second aspect of the present invention, the excavation head is detachably engaged with the excavation rotating shaft, and after the predetermined length of drainage material is dug into the ground, the excavation rotation shaft is pulled out and left in the ground together with the drainage material. The gist is to do.

  According to the second aspect of the present invention, the excavation head is left in the ground together with the drainage material, so that the drainage material can be installed without difficulty.

  The gist of the present invention described in claim 3 is that the drainage material is installed in the perforated PVC pipe.

  According to this invention of Claim 3, a porous PVC pipe | tube can be arrange | positioned on the outer side of drainage material, and this can be installed simultaneously.

  In the present invention according to claim 4, after the drainage material and the perforated PVC pipe are installed, the perforated PVC pipe is pulled out, the end of the drainage material is exposed from the perforated PVC pipe, and the exposed portion is defined as the water collecting portion. The gist is to do.

  According to the present invention, the end of the drainage material is exposed from the perforated PVC pipe, and the perforated PVC pipe is disposed at the same time by setting the exposed portion as the water collecting portion. Even in the case where water is collected, water can be collected even at portions other than the perforated PVC pipe, and the drainage performance can be further enhanced.

  The gist of the present invention described in claim 5 is to dig the inside of the existing drain pipe.

  According to this invention of Claim 5, this invention can be utilized as reproduction | regeneration of the existing drain pipe.

  The present invention described in claim 6 is characterized in that the excavation head is formed with a boss hole into which the boss at the distal end of the excavation rotating shaft fits in the main body portion, and a blade that extends elliptically toward the original pointed portion. It is what.

  According to the sixth aspect of the present invention, the excavation head and the excavation rotation shaft can be secured and removed by the boss and the boss hole, and the arrowhead bites into the excavation head by providing the blade extending in an elliptical shape. Reliable excavation is obtained.

  The gist of the present invention described in claim 7 is that the excavation rotating shaft is rotationally driven by a handy type driving machine.

  According to this invention of Claim 7, it can construct simply with a handy type drive.

  As described above, the groundwater drainage installation method according to the present invention allows drainage with no vibration, no noise, and no soil without damaging the filter even if the drainage material has a filter for preventing inflow of sediment on the outer periphery. It can be used for installation of materials.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an explanatory view showing an embodiment of a groundwater drainage material installation method according to the present invention, which is a regeneration method when an existing drainage pipe 4 is installed.

  In the figure, reference numeral 5 denotes a drainage material used in the present invention, wherein the outer periphery of a synthetic resin drainage pipe 6 having a large number of water permeable holes formed on the peripheral wall thereof is covered with a nonwoven fabric filter 7 and pressed by a geotextile net 8 from above. .

  The synthetic resin drain pipe 6 is not particularly limited. As an example, for example, a resin string, that is, a synthetic resin made of a thermoplastic material such as polypropylene, polystyrene, polyethylene, or polyester, is heated and melted to have a diameter of about 1 to 6 mm (standard). Laminate that is extruded in the shape of a string with a constant diameter (diameter 2 mm) and is irregularly curled in order to sequentially laminate resin strings (linear synthetic resin), and has a hole in the center along the length direction. A material in which mutual contact portions of string-like polypropylene, polystyrene, polyethylene, or polyester are welded and formed into a hollow cylindrical shape is preferable.

  The synthetic resin drainage pipe 6 in which the resin strings (linear synthetic resins) are sequentially laminated has a predetermined hole formed in the central portion along the length direction, is substantially flexible and has high pressure resistance. The surface opening ratio is 90 to 95% (changes depending on the density), and the porosity is 85 ± 5% (the density and the like can be adjusted).

  Although not shown as another example of the synthetic resin drain pipe 6, a thermoplastic resin cage in which a plurality of water permeable holes penetrating in the inner and outer directions are formed in the peripheral wall so as to extend linearly in the same direction. It may be due to the shape.

  The thermoplastic resin is polyester, polypropylene, or the like, and each water permeable hole is formed so as to extend from the outer peripheral surface to the inner peripheral surface of the thermoplastic resin cage.

  The nonwoven fabric filter 7 is a nonwoven fabric having a thickness of about 1 mm or 2 mm, for example, and is made of a thermoplastic resin (made of polyester, polypropylene, or the like).

  The geotextile net 8 is a cell force that has a structure in which a strip made of stretched polypropylene tape and a strip of ethylene / vinyl acetate copolymer resin are woven in a grid shape and the intersections are integrated by heat fusion. Asahi Kasei Kogyo Co., Ltd. (registered trademark name) is suitable, and is excellent in tensile strength characteristics, creep characteristics, impact resistance, durability, friction characteristics with soil, and chemical resistance necessary as a reinforcing material.

  SELFORCE can build a highly safe earth structure, especially in impact resistance, even if the embankment material is rocky, even if the embankment material is rocky, the strength decrease due to damage during leveling and rolling is small (strength retention rate of 94% or more). The creep reduction coefficient is large (0.65), and in the present invention, the nonwoven fabric filter 7 is covered and protected from the outside with such a geotextile net 8. The geotextile net 8 is fixed by clip fastening or adhesion.

  In the present invention, a pointed excavation head 9 is installed at the head of the drainage material 5, and the excavation rotary shaft 10 inserted into the drainage material 5 rotates the excavation head 9 to dig into the natural ground.

  3 and 4 show details of the excavation head 9. The excavation head 9 has a boss hole 9b into which the boss 10a at the distal end of the excavation rotating shaft 10 fits in the rear end hollow portion of the main body portion 9a, and has a pointed tip portion. 9c was provided with a blade 9d that spreads in an elliptical shape toward the root in a plan view from the tip.

  As for the relationship between the boss 10a and the boss hole 9b, a rectangular shape (square) is selected so that the boss 10a can be easily extracted from the boss hole 9b and the rotational force of the excavation rotary shaft 10 can be reliably transmitted to the excavation head 9. did.

  The excavation head 9 may be made of hard metal, but is preferably made of hard plastic as an inexpensive one.

  Further, as shown in FIGS. 5 to 7, the driving source of the excavation rotating shaft 10 may be a handy type driving machine 11, and the excavation rotating shaft 10 is rotationally driven by the handy type driving machine 11. In the case of large-scale construction, it is possible to use a fixed drive device.

  In the case of regeneration when the existing drainage pipe 4 is installed, even if the existing drainage pipe 4 is buried, excavation is easier than in the case of new piping, and the excavation head 9 is drained as shown in FIG. The excavation rotary shaft 10 is passed through the drainage material 5 at the front end of the material 5, and a handy type driving machine 11 is set at the rear end.

  As shown in FIG. 6, the excavation is continued by excavating the existing drainage pipe 4 so that the drainage material 5 comes out from the tip of the existing drainage pipe 4.

  Thereafter, as shown in FIG. 7, if the excavation head 9 and the drainage material 5 are left and the excavation rotary shaft 10 is pulled out, the installation of the drainage material 5 is completed, and the portion of the drainage material 5 coming out from the tip of the existing drainage pipe 4 is When the existing drainage pipe 4 is a perforated pipe, it functions as a water collecting section. It is also submerged from its peripheral surface. In either case, the water flows through the synthetic resin drainage pipe 6, Drained.

  In addition to the case where the drainage material 5 is buried in this way, as shown in FIG. 1, the drainage material 5 is installed in the perforated PVC pipe 12 and may be set on the excavation rotating shaft 10 together with the perforated PVC pipe 12. it can.

  In order to dig the perforated PVC pipe 12 and the drainage material 5 and to collect water more reliably, after the excavation is completed, the perforated PVC pipe 12 is pulled out as shown in FIG. Let it come out and secure the exposed part as the water collection part A.

  The installation of the perforated PVC pipe 12 is effective in preventing clogging of the existing drainage pipe 4.

  Although the above embodiment demonstrated the case of the reproduction | regeneration in case the existing drainage pipe 4 is installed, when the drainage material 5 is installed as a new drainage pipe, the drainage of a new bank, the drainage of a parent bank, water The present invention can be applied to various fields such as a retaining wall without a punched pipe and a drainage to a natural slope.

  In that case, it is possible to install the drainage material 5 without the perforated PVC pipe 12 alone, but if it is installed together with the perforated PVC pipe 12, a satisfactory construction can be obtained in this case as well. In order to dig up the PVC pipe 12 and the drainage material 5 and to collect water more reliably, after the excavation is completed, the perforated PVC pipe 12 is pulled out and the tip of the drainage material 5 is exposed to the ground, Secured as water collection part A.

It is explanatory drawing which shows one Example of the drainage material installation method of the natural ground of this invention. It is a vertical side view which shows the post process of one Example of the drainage material installation method of the natural ground of this invention. It is a vertical side view of an excavation head. It is a rear view of an excavation head. It is a side view which shows the 1st process of the drainage material installation procedure of the drainage material installation construction method of the natural ground of this invention. It is a side view which shows the 2nd process of the drainage material installation procedure of the drainage material installation method of the natural ground of this invention. It is a side view which shows the 3rd process of the drainage material installation procedure of the drainage material installation method of the natural ground of this invention. It is explanatory drawing which shows a prior art example.

DESCRIPTION OF SYMBOLS 1 ... Drain pipe 2 ... Driving pipe 3 ... End cap 4 ... Existing drain pipe 5 ... Drainage material 6 ... Synthetic resin drain pipe 7 ... Nonwoven fabric filter 8 ... Geotextile net 9 ... Excavation head 9a ... Main-body part 9b ... Boss hole 9c ... Tip point 9d ... blade 10 ... excavation rotary shaft 10a ... boss 11 ... handy type drive 12 ... perforated PVC pipe

Claims (7)

  The drainage material is made by covering the outer periphery of a synthetic resin drainage pipe with a large number of water-permeable holes on its peripheral wall with a non-woven fabric filter and holding it with a geotextile net from above, with a pointed drilling head at the top of the drainage material. The groundwater drainage material installation method, characterized in that the drainage material is dug into the natural ground while rotating the excavation head with the excavation rotating shaft installed and inserted into the drainage material.   The excavation head is detachably engaged with an excavation rotary shaft, and after a predetermined length of drainage material is excavated in the natural ground, the excavation rotary shaft is pulled out and left in the ground together with the drainage material. Drainage material installation method.   The drainage material installation method for a natural ground according to claim 1 or 2, wherein the drainage material is installed in a perforated PVC pipe.   4. After installing the drainage material and the perforated PVC pipe, pull out the perforated PVC pipe, expose the end of the drainage material from the perforated PVC pipe, and use the exposed part as the water collecting part. Drainage material installation method.   The drainage material installation method of the natural ground in any one of Claim 1 thru | or 4 which excavates the inside of the existing drainage pipe.   6. The excavation head is formed with a boss hole into which a boss at a distal end of an excavation rotating shaft is fitted in a main body portion, and a blade that extends in an elliptical shape toward the original is provided at a tip sharpened portion. The drainage material installation method of the natural ground. The ground excavation material installation method according to any one of claims 1 to 6, wherein the excavation rotating shaft is rotationally driven by a handy type driving machine.

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