JP2007314963A - Drain structure and drain structure construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drain structure which facilitates construction thereof irrespective of the degree of inclination of a slope, and achieves positive draining. <P>SOLUTION: The drain structure embedded inside a rear slope 12 of a bank 10 is formed of three cages 31, 32, 33 each made of a metal mesh. The cages 31, 32, 33 are filled with broken stones 23, 23, etc. According to the drain structure, each of the cages 31, 32, 33 has no metal mesh lid on an upper surface thereof, and the broken stones 23, 23, etc. are covered with a soft and water-permeable sheet 37, which leads to easy construction of the drain structure and positive draining of percolating water. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a drain structure and a drain structure construction method, and more particularly, to a drain structure and a drain that are embedded in a ground that is an inclined surface and discharge permeated water that has penetrated into the ground into a drainage channel that is installed below the inclined surface. It relates to the construction method of the structure.

  On slopes such as mountainsides, dikes, and beaches, landslides may occur due to water that has penetrated due to rainfall. For example, in a river embankment, as shown in FIG. 18, the infiltrating surface 16 in the embankment is caused by rainfall or water penetrating from the river 14 during a flood or the like (the slope opposite to the river side). It becomes higher than the bottom of the slope (the lower end of the slope) and water leaks, or it is eroded and collapsed. One of such measures for water leakage and seepage erosion is drain work. The drain construction is a structure in which, for example, a drainage layer made of gravel or the like is formed on the back edge of the dike, and the infiltrating surface 16 in the levee body is made lower than the back edge of the back wall, and the permeated water is drained from the drainage layer.

  In Patent Document 1, a grid-like water-permeable pipe constructed by connecting water-permeable pipes such as net pipes in a vertical and horizontal grid pattern is arranged inside the back side of a dike and so on along the slope. The lower end is guided to the outside by a drain pipe, and a permeable mat of entangled fibers is respectively wound around the lateral permeable pipe of each step, which is a horizontal member constituting the lattice-shaped permeable drain pipe, at appropriate intervals, and A drain structure is described in which each wrapping end is extended laterally toward the inside of the levee body to form a priming mat belt portion.

  In Patent Document 2, a dam body infiltrated is formed on a foundation ground on the river back side of a levee body, and is formed by a filling rod filled with a coarse filter material filled with a steel assembly net through which osmotic water passes. It is composed of a smoke drain that allows water to flow in, a dyke channel provided at the bottom of the back of the levee, and a coarse filter material that allows permeate to pass through. And a drain layer that leads the permeated water flowing into the smoked drain part to the dike channel, and the drain layer has a thickness lower than the height of the smoked drain part. The drainage structure of the dike covered with soil is described.

Moreover, although it is not the drain structure of a river dike, patent document 3 describes the drain structure which stabilizes a beach by efficiently draining the wave going up to the beach and lowering the groundwater level.
Japanese Utility Model Publication No. 57-60917 JP 2002-121720 A JP-A-7-207639

  However, in the drain structure described in Patent Document 1, since the portion where the permeated water flows is a pipe, when the amount of permeated water increases, all cannot be discharged, and water leakage and permeation erosion occur. Moreover, since the pipe is easily clogged, there is a possibility that the discharge function of the permeated water may be remarkably deteriorated.

  On the other hand, since the drain structure described in Patent Document 2 requires a drain layer connecting the smoked drain part and the dike channel, it is difficult to construct unless it is a long gentle slope, and the applicable slope is In addition to being limited, it is necessary to increase the excavation distance from the dike channel to the river side, and the construction becomes large. In addition, the drain structure described in Patent Document 3 returns seawater that has risen from the sea to the beach through the basement and returns to the sea, and there is a problem that application to river embankments is difficult.

  This invention is made | formed in view of this point, The place made into the objective provides the drain structure in which construction can be performed easily regardless of the magnitude of the slope of a slope, and reliable drainage is possible. There is.

  In order to solve the above-mentioned problems, the first drain structure of the present invention is embedded in the ground which is a slope, and discharges the permeated water that has penetrated into the ground into a drainage channel installed below the slope. It is a drain structure, is formed of a cage made of a wire mesh filled with a coarse filter material through which the permeated water passes, and has a smoked drain portion that guides the permeated water to the drainage channel, The smoked drain part is formed by stacking a plurality of the firewoods and is covered with earth and sand, and the firewood is located on the near side when viewed from the lower end of the slope toward the slope. A front metal mesh, a rear metal mesh on the back side, and a bottom metal mesh on the bottom surface, and the front metal mesh, the back metal mesh, and the bottom metal mesh are made of self-supporting metal mesh panels, and the front metal mesh of the plurality of stacked stacks Each of The heel placed on the side is arranged on the near side from the lower end of the slope toward the slope, the upper surface side of the heel is open, and the upper surface other than the part where the other heel is stacked is A flexible and water-permeable sheet was laid on the filter material. By having such a configuration, a large amount of permeated water surely flows through the gaps between the coarse filter materials filled in the cage made of a wire mesh. Here, the self-supporting wire mesh panel is a wire mesh panel that holds the panel shape without assistance when standing vertically, such as a panel made of welded wire mesh or expanded metal, a panel with a diamond wire mesh stretched on a steel bar frame, etc. Can be mentioned. In the case of a structure in which a rhombus wire mesh is connected with a wire like a futon bag, the wire mesh will be crushed unless the lifting force is applied, so this cannot be said to be a self-supporting wire mesh panel. A welded wire mesh is a wire mesh that is formed by welding metal wires or rods that are perpendicular to each other at right angles to each other and welding the intersections. Therefore, even a thin wire diameter can withstand a large load weight.

  The drainage channel is installed at the lower end of the slope, and is in contact with the smoked drain part by a back surface part, and the back surface part of the drainage channel has a through hole or a water permeation through which the permeated water passes. It is preferable that a member is provided. Here, the water permeable member is provided on the back surface means that at least a part of the back surface portion is made of a water permeable member. When the drainage channel is made of concrete, the back surface portion is made of porous concrete. As an example.

  It is preferable that a part of the bottom wire mesh and the front wire mesh, and another part of the bottom wire mesh and the back wire mesh are integrally formed.

  It is preferable that the sheet covers the back metal mesh.

  Here, the coarse-grain filter material has a larger particle size and better water permeability than the earth and sand constituting the ground which is a slope, such as gravel, stone, rock crushed material, concrete crushed material, etc. Can be mentioned.

  The second drain structure of the present invention is a drain structure that is embedded in the ground as a slope and discharges the permeated water that has permeated into the ground into a drainage channel that is installed below the slope. Is installed at the lower end of the slope, and when viewed from the lower end of the slope toward the slope rather than the drainage channel, it is made of a self-supporting wire mesh panel on the back side and the bottom and A back side bent wire mesh panel is installed so that a bottom surface portion extends from the upright side to the near side, and allows the permeated water to pass from the drainage channel to the upright side portion of the back side bent metal mesh panel. A layer of the coarse filter material is formed, and a part of the layer of the coarse filter material is placed on the bottom surface portion of the back side bent metal mesh panel, and the vertical surface of the back side bent metal mesh panel And an upper surface of the coarse filter material layer But it has a structure that is covered by having a flexible and permeable sheet. With such a configuration, a large amount of permeated water surely flows through the gaps between the coarse filter materials.

  Between the drainage channel and the layer of the coarse filter material is a front side bent wire mesh panel comprising a self-supporting wire mesh panel and having a bottom surface portion and a vertical surface portion, and a bottom surface portion from the vertical surface portion to the back side. It is installed so as to extend, and an elevation surface portion of the front side bent wire mesh panel is sandwiched between the drainage channel and the coarse filter material layer, It is preferable that a part of the layer of the coarse filter material is placed.

  The drainage channel has a back surface portion that is in contact with the layer of the coarse filter material or the vertical surface portion of the front side bent metal mesh panel, and the back surface portion of the drainage channel includes the permeated water. It is preferable that a through hole or a water-permeable member through which the water passes is provided.

  Above the back side bent wire mesh panel, an upper bent wire mesh panel made of a self-supporting wire mesh panel and provided with a bottom surface portion and an elevation surface portion is installed so that the bottom surface portion extends from the elevation surface to the near side, A part of the coarse filter material layer is also placed on the bottom surface of the upper folded wire mesh panel, and the raised surface of the upper folded wire mesh panel is made of the flexible and water-permeable sheet. Preferably it is covered.

  The construction method of the first drain structure of the present invention is a construction method of a drain structure that is embedded in the ground which is a slope and drains the permeated water that has penetrated into the ground into a drainage channel installed below the slope. The drain structure has at least two ridges made of a self-supporting wire mesh panel and having an open upper surface, and the ridges are a front wire mesh arranged on the front side from the lower end of the slope toward the slope and the back. A back metal mesh disposed on the side, a step of installing the first ridge on a substantially horizontal foundation ground inside and below the slope, and a coarse filter on the first ridge A step of filling the material, a second ridge on the first ridge, and a front metal mesh of the second ridge is substantially parallel to the front metal mesh of the first ridge and more than the front metal mesh of the first ridge Install so that it is located on the back side from the bottom of the slope toward the slope. A step of filling the second ridge with a coarse filter material, and a flexible and water-permeable surface on the exposed surface of the filter material filled in the first and second ridges. And a step of covering the sheet with earth and sand.

  Furthermore, it is preferable to include a step of bringing the front metal mesh of the first ridge into contact with the drainage channel.

  The construction method of the second drain structure of the present invention is a construction method of the drain structure that is embedded in the ground which is a slope and discharges the permeated water that has penetrated into the ground into a drainage channel installed below the slope. And on the substantially horizontal foundation ground that exists inside and below the slope, a back-side folded wire mesh panel comprising a self-supporting wire mesh panel and having a bottom surface portion and an elevation surface portion is formed from the lower end of the slope toward the slope. A step of installing the bottom surface portion on the front side so as to extend from the elevation surface portion, and a layer of a coarse filter material above the foundation ground from the elevation surface portion of the back side bent wire mesh panel to the lower end of the slope. A step of forming, a step of covering the upright portion of the back folded wire mesh panel and the upper surface of the filter material layer with a flexible and water-permeable sheet, and a step of covering the sheet with earth and sand. Including.

  In a preferred embodiment, the step A is a step of forming a coarse filter material layer up to the drainage channel placed at the lower end of the slope.

  In a preferred embodiment, the step A includes a front-side folded wire mesh panel comprising a self-supporting wire mesh panel at the lower end of the slope and having a bottom surface portion and an elevation surface portion, and the bottom surface portion extending from the elevation surface portion to the back side. And forming a coarse layer of filter material from the elevation surface portion of the back side bent wire mesh panel to the elevation surface portion of the near side bent wire mesh panel.

  In a preferred embodiment, after the step A, an upper bent wire mesh panel made of a self-supporting wire mesh panel and having a bottom surface portion and an elevation surface portion is disposed on the front side from the elevation surface portion above the back side bent wire mesh panel. And a step of placing a coarse filter material on the bottom surface of the upper bent wire mesh panel.

  The first drain structure of the present invention has a smoked drain portion formed by stacking a plurality of baskets made of wire mesh, and the basket is filled with a coarse filter material, so that construction is easy. Thus, the permeated water can be surely drained. Since the second drain structure of the present invention is a structure having a back side bent wire mesh panel and a coarse filter material layer, it can be applied easily and in a short time, and the permeated water can be surely secured. Can be drained.

  Before describing the embodiment of the present invention, the present inventors have considered another drain structure using a wire netting, so this consideration will be described. This wire mesh bag is a so-called futon bag. The important points in the drain structure are the size of the cross-sectional area in the section perpendicular to the longitudinal direction of the levee body (hereinafter referred to as the capacity), and the side closest to the river of the drain structure at the same level as the drainage channel ( It is the point how close the heel part is to the river.

  FIG. 19 shows a drain structure assumed when the inclination angle of the back slope 12 of the levee body 10 is about 25 degrees. This drain structure is used as a comparative example. It is set as the smoked drain part which fills the cracks 40 and 40 which consist of a rhombus metal net with cracked stone, and lets permeate flow. The smoked drain part is installed in the back slope 12 with rectangular parallelepiped gauze fences 40, 40 inclined substantially the same as the back slope 12, and a heel part is brought closer to the river 14 by placing a stone 41 below it. The capacity is increased, and the top surface of the smoke drain is covered with earth and sand. In addition, a drain layer 42 is provided for connecting the drainage channel 20 installed at the back butt and the smoked drain portion. The drain layer 42 is a wire mesh basket installed horizontally. The reason for providing the drain layer 42 is that when the drainage channel 20 is brought into direct contact with the smoked drain portion installed at an inclination, the drainage channel 20 is pressurized from the smoked drain portion, and the drainage channel 20 is in the right side of the figure. Because it will fall over.

  Since the drain structure of the comparative example is installed with the wire mesh fence 40 inclined, if the inclination angle becomes large, there is a risk that the wire mesh fence 40 may slide down in the inclination direction, making the construction difficult, and the dam body with a gentle slope It can be applied only to 10 and construction on a gentle slope is also difficult. Furthermore, since the drain layer 42 which is a horizontal part is required, an extra area | region is required for the installation from a back surface bottom to a horizontal ground.

  In addition, considering the construction, the drain structure of the comparative example shown in FIG. 19 is supported by placing a wire mesh rod 40 on the ground excavated on the slope so as not to be crushed. It is necessary to do the work of stuffing stones. Therefore, it is a large and troublesome work, and it takes time and cost. In addition, the cage made of rhombus wire swells in the horizontal direction due to the pressure of the stone after the stones are piled up or the pressure of the earth and sand on the stone, so that the drainage channel 20 is damaged due to the force applied to the drainage channel 20. There is a fear.

  In view of such considerations and the problems of the drain structure described in Patent Documents 1 to 3, the inventors of the present application have come up with the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following drawings, components having substantially the same function are denoted by the same reference numerals for the sake of brevity.

(Embodiment 1)
A schematic cross section of the drain structure according to Embodiment 1 is shown in FIG. In order to make the drawing easier to see, many of the hatching representing the cross section are omitted in FIG. 1 and the subsequent drawings. The drain structure according to the present embodiment is embedded in the ground of the back slope (slope) 12 of the levee body 10, and the infiltrating surface 16 in the levee body continuous from the water surface of the river 14 is formed on the back slope 12 side. The permeated water is led down to the drainage channel 20 installed at the back end. This drain structure is composed of three ridges 31, 32, 33 made of wire mesh, and the ridges 31, 32, 33 are filled with crushed stones 23, 23,. Yes. Since the cracked stones 23, 23,... Have a diameter of several centimeters to several tens of centimeters, the permeated water flows through these gaps. A flexible and water-permeable sheet 37 such as a nonwoven fabric is hung on the upper surface, rear surface (river 24 side), and side surfaces of the ridges 31, 32, 33 so that earth and sand do not enter the gap between the filter materials.

  As shown in FIG. 1, the drain structure according to the present embodiment has a stepped shape that increases in order from the lower end of the back surface 12 toward the upper end side of the back surface 12 in the cross section. The earth and sand 22 is put on the top. The angle formed by the back slope 12 and the horizontal plane is 27 °. The first ridge 31 constituting the lowermost stage of the drain structure is installed on the foundation ground 21 below the back slope 12 (inside the ground that is vertically below the back slope 12), and above it. A second ridge 32 is stacked, and a third ridge 33 is stacked thereon. The foundation ground 12 is excavated substantially horizontally.

  FIG. 2 is a side view of the stacked structure of the cages 31, 32, and 33 constituting the drain structure. The metal meshes that form the cages 31, 32, and 33 and the cages 31, 32, and 33 are connected and fixed by coils 51, 51,.

  FIG. 3 is a perspective view in which the wire mesh constituting the lowermost first brim 31 is separated. The first hook 31 includes an L-shaped front side L-shaped metal mesh (front side bent metal mesh panel) 57 in which the front metal mesh 53 and a part of the bottom metal mesh are integrated, a rear metal mesh 52 and a bottom metal mesh. It is composed of an L-shaped rear-side L-shaped metal mesh (back-side bent metal mesh panel) 56, a bottom-side intermediate metal mesh 54, and two side-surface metal meshes 55, 55 that are partly integrated with each other. Each wire mesh consists of a rectangular welded wire mesh that connects steel bars and metal wires. The front-side L-shaped metal mesh 57 and the back-side L-shaped metal mesh 56 are made by bending a rectangular flat welding metal mesh, and have the same shape and are interchangeable. Further, the front side L-shaped metal mesh 57 and the back side L-shaped metal mesh 56 are L-shaped on surfaces perpendicular to the front surface and the back surface, respectively. These wire meshes are fixed to each other by being connected to each other by adjacent wire meshes and coils 51 (only one is shown and the others are omitted), and assembled into a bag shape. In the present embodiment, these wire meshes are made of iron wire that has been subjected to rust prevention processing (for example, hot dip galvanization, zinc aluminum alloy plating, etc.).

  FIG. 4 is a perspective view in which the metal nets constituting the second cage 32 placed on the first cage 31 are separated. Since the second ridge 32 is substantially the same as the first ridge 31 and only a part thereof is different, the different portion will be described.

  The bottom intermediate wire mesh 64 of the second bar 32 has a length in the front-rear direction smaller than that of the first bar 31. The lengths of the side wire meshes 65 and 65 are similarly reduced. .

  FIG. 5 is a perspective view in which the metal mesh constituting the third ridge 33 placed on the second ridge 32 is separated. Since the third ridge 33 is substantially the same as the second ridge 32 and only a part thereof is different, the different portion will be described.

  The third rod 33 does not have a bottom intermediate wire mesh, and the lengths of the side wire meshes 75 and 75 are reduced accordingly.

  The front metal mesh 53, the back metal mesh 52, and the side metal mesh 55, 65, 75 are rectangular in any of the saddles 31, 32, 33.

  As shown in FIGS. 2 to 5, the rectangular parallelepiped portions of the three flanges 31, 32, and 33 have the same size and shape of the front metal mesh 53 and the rear metal mesh 52, but the bottom and side surfaces in the front-rear direction. The length is different. On the bottom surface, the difference in length is adjusted by inserting bottom metal meshes 54 and 64. The side wire meshes 55, 65, 75 correspond to each other by changing the length itself.

  FIG. 6 is a perspective view of the drainage channel 20. The drainage channel 20 is made of concrete and has a J-shape in a cross-sectional view. The back surface portion 27 is formed higher than the front surface portion, abuts against the front wire mesh 53 of the first ridge 31, and the water that has flowed through the first ridge 31 is provided in the back surface portion 27. 28,... Flows into the groove of the drainage channel 20 and flows through the drainage channel 20 to be discharged.

  Next, the construction method of the drain structure of this embodiment is demonstrated.

  First, in FIG. 1, the back slope 12 side of the dam body 10 is excavated to form a substantially horizontal foundation ground 21. And the drainage channel 20 is installed in the part used as a back butt. The position of the drainage channel 20 is strictly determined in advance, and it is very difficult to put a stone in a wire netting and install it in a precise position, so the drainage channel 20 is first installed.

  Next, a sheet 37 having flexibility and water permeability such as a non-woven fabric is formed on the foundation ground 21, and the wire mesh group shown in FIG. 31 is assembled and installed. The sheet 37 is brought into the construction site in a roll shape, and after being laid on the foundation ground 21, the rest remains in a roll shape and is placed in the vicinity of the back metal mesh 52 of the first trough 31. The front wire mesh 53 is installed in contact with the back surface portion 27 of the drainage channel 20. At this time, the front-side L-shaped metal mesh 57 and the rear-side L-shaped metal mesh 56 are self-supporting, and the side-surface metal meshes 55 and 55 are also leaned against the front-side L-shaped metal mesh 57 and the rear-side L-shaped metal mesh 56. There is no need to support it, and it can be easily installed in a short time with a small number of people.

  Then, the first basket 31 is filled with the cracked stones 23, 23,.

  4 is placed on the first cage 31 filled with the walnut stones 23, 23,..., And the second cage 32 is assembled and installed by connecting the meshes with the coil 51. Also in this case, it can be installed easily and in a short time by a small number of people as in the assembly of the first basket 31. At this time, the back metal meshes 52 and 52 of the two hooks 31 and 32 are arranged so as to be flush with each other, and the upper and lower hooks 31 and 32 are also connected using the coil 51. In a state where the second ridge 32 is installed, a part of the back side of the back slope 12 of the first ridge 31 is covered with a bottom surface of the second ridge 32. Further, the front metal mesh 53 of the second cage 32 is located behind the front metal mesh 53 of the first cage 31, and the two front metal meshes 53, 53 are substantially parallel.

  After this, the second basket 32 is filled with the split stones 23, 23,. In this way, when the walnut stones 23, 23,... Are filled, the state shown in FIG. In FIG. 7, the coil 51 is omitted for easy viewing.

  Next, a group of wire meshes shown in FIG. 5 is placed on the second cage 32 filled with the walnut stones 23, 23,... . Also in this case, it can be installed easily and in a short time by a small number of people as in the assembly of the first basket 31. At this time, similarly to the case where the second cage 32 is installed, the rear meshes 52, 52, 52 of the three cages 31, 32, 33 are arranged so as to be flush with each other, and the upper and lower cages 32, 33 are arranged. The coil 51 is also used for the connection between them. In the state where the third rod 33 is installed, the bottom surface of the third rod 33 is covered with a part of the back side of the back slope 12 of the second rod 32 as when the second rod 32 is installed. I am doing. The front metal mesh 53 of the third cage 33 is located behind the front metal mesh 53 of the second cage 32, and the two front metal meshes 53, 53 are substantially parallel.

  Then, the third basket 33 is filled with the cracked stones 23, 23,.

  Further, as shown in FIG. 8, a flexible and water-permeable sheet 37 wound in a roll shape is spread to cover the back metal nets 52, 52, 52 of the three baskets 31, 32, 33, and then further spread. Then, lay it on the exposed surface of the filled split stones 23, 23,. Further, the front metal mesh 53 of each of the second and third baskets 32 and 33 is also covered with a sheet in the process of spreading from the roll shape. Thus, as shown in FIG. 9, the upper surface, the front surface, and the back surface of each of the collars 31, 32, 33 are covered with the sheet 37. Since the front metal mesh 53 of the first trough 31 is in contact with the back surface portion 27 of the drainage channel 20, it is not covered with the sheet 37. In FIGS. 8 and 9, the coil 51 is omitted for easy viewing. Then, the side surfaces of the ridges 31, 32, 33 are also covered with the sheet 37.

  Next, the drain structure shown in FIG. 1 is completed by covering the sheet 37 with the earth and sand 22. Planting plants such as turf on the earth and sand 22 is preferable because it prevents the earth and sand 22 from collapsing.

  The drain structure according to the present embodiment has the structure described above, and has the following effects.

  The drain structure according to the present embodiment is formed by stacking three ridges 31, 32, 33 made of a plurality of wire meshes, and the front side L-shaped wire mesh 57 that is a constituent member of these ridges 31, 32, 33. And the rear side L-shaped metal mesh 56 can be used in common for all the cages 31, 32, 33, so that the manufacturing cost of the cages 31, 32, 33 is reduced. Since the pots 31, 32, and 33 are filled with the cracked stones 23, 23,..., A large amount of permeated water can be reliably drained. In addition, the inclination angle of the back slope 12 varies depending on the construction site, but any inclination angle can be accommodated by adjusting the length in the front-rear direction of the bottom intermediate metal meshes 54, 64. Get smaller. And since the main body parts (front, back, side, bottom) of the rods 31, 32, and 33 are made of a welded wire mesh, they have high strength and rigidity and are self-supporting. Because it is open, installation work can be done easily. Furthermore, the upper surface and the side surface can be prevented from being disturbed by the penetration of permeated water due to the earth and sand entering between the cracked stones 23, 23,. Can be lowered.

  Since the three ridges 31, 32, and 33 are all stacked in a horizontal plane and have sufficient structural strength against the horizontal force, the horizontal force is not applied to the drainage channel 20. Accordingly, there is no need to provide the horizontal drain layer 42 as shown in FIG. 19, and the horizontal installation area can be reduced accordingly. For this reason, it is possible to secure a wide private area on the back slope 12 side and a road under the bank.

(Embodiment 2)
FIG. 10 shows a schematic side view of the drain structure according to the second embodiment. The drain structure according to the present embodiment is formed by stacking three ridges 61, 62, and 63 made of wire mesh as in the first embodiment, but the embodiment is that the back wire mesh of each heel is not flush. Since the other points are the same as those of the first embodiment, only the differences from the first embodiment will be described.

  In the drain structure of the present embodiment, the rear metal mesh of the second collar 62 is disposed rearward of the rear metal mesh of the first collar 61, and the third collar is disposed behind the rear metal mesh of the second collar 62. The rear metal mesh 63 is disposed rearward. Therefore, the amount of excavation can be reduced as compared with the drain structure of the first embodiment, but the heel portion (the portion closest to the river 14 of the drain structure that is substantially the same level as the drainage channel 20) is far from the river 14. Drainage tends to be insufficient, and the maximum drainage volume may be reduced due to the small capacity. Other effects are the same as those of the first embodiment.

(Embodiment 3)
A schematic side view of the drain structure according to Embodiment 3 is shown in FIG. The drain structure according to the present embodiment is formed by stacking three ridges 71, 72, 73 made of wire mesh as in the first embodiment, but the embodiment is that the back wire mesh of each heel is not flush. Since the other points are the same as those of the first embodiment, only the differences from the first embodiment will be described.

  In the drain structure of the present embodiment, the rear metal mesh of the second collar 72 is disposed in front of the rear metal mesh of the first collar 71, and the third collar than the rear metal mesh of the second collar 72. The rear metal mesh 73 is arranged in front. Therefore, it is necessary to increase the amount of excavation for installation as compared with the drain structure of Embodiment 1, and the cost increases. However, since the capacity is large and the heel part is close to the river 14, the drainage capacity is large. Other effects are the same as those of the first embodiment.

(Embodiment 4)
A schematic side view of the drain structure according to Embodiment 4 is shown in FIG. The drain structure according to the present embodiment is not made of a heel made of a welded wire mesh, but has a structure in which a part of the bottom surface of the heel is missing.

  Specifically, the back side bent metal mesh panel 156 having the same shape as the back side L-shaped metal mesh 56 of the first embodiment is placed on the back side on the foundation ground 21, and the front side L type of the first embodiment is placed on the front side. A front-side bent wire mesh panel 157 having the same shape as the wire mesh 57 is placed. Here, the back side refers to the back slope side when facing from the bottom of the back slope (slope) toward the back slope, and the near side is the opposite side. The back side bent metal mesh panel 156 includes an elevation surface portion and a bottom surface portion, and the bottom surface portion is placed on the foundation ground 21 so as to extend from the elevation surface portion toward the near side. Further, the front-side bent wire mesh panel 157 also includes an elevation surface portion and a bottom surface portion, and the bottom surface portion is placed on the foundation ground 21 so as to extend from the elevation surface portion to the back side. And both bottom face parts are placed apart, and the split stones 23, 23,... Are placed directly on the foundation ground 21 in the separated parts. Since the back side bent metal mesh panel 156 and the front side bent metal mesh panel 157 have the same configuration and shape as the back side L type metal mesh 56 and the front side L type metal mesh 57 of the first embodiment, respectively, description thereof is omitted. To do.

  In the present embodiment, the upright portion of the front side bent metal mesh panel 157 is in contact with the back surface portion of the drainage channel 20. This drainage channel 20 is shown in FIG. Although not shown, the drain structure of the present embodiment has side wire meshes made of welded wire meshes on both side surfaces, and these side wire meshes are connected to the back side bent metal mesh panel 156 and the front side bent metal mesh panel 157, respectively. Connected and fixed. The side wire mesh is the same as the side wire mesh of the first embodiment. .., Which are packed with coarse filter materials 23, 23,..., Which are coarse filter materials, are packed in the regions surrounded by the vertical surfaces of the back side bent wire mesh panel 156 and the front side bent wire mesh panel 157 and the side wire mesh. A layer of material is formed. Since a layer of filter material is placed on the bottom surface of each of the back side bent metal mesh panel 156 and the front side bent metal mesh panel 157, both the metal mesh panels 156 and 157 do not move on the foundation ground 21. It is fixed. A flexible and water-permeable sheet 37 is laid on the foundation ground 21 below the filter material layer.

  Further, a sheet 37 is laid directly on the split stones 23, 23,. Further, the elevational side portion and the side wire mesh of the back side bent wire mesh panel 156 are also covered with the sheet 37.

  Next, the construction method of the drain structure of this embodiment will be described.

  First, in FIG. 13, the back slope side of the levee body is excavated to form a substantially horizontal foundation ground 21. And the drainage channel 20 is installed in the part used as a back butt.

  Next, a flexible and water-permeable sheet 37 such as a non-woven fabric is laid on the foundation ground 21, and the back side bent metal mesh panel 156, the front side bent metal mesh panel 157, and the side wire mesh are placed on the coil. Each panel and side wire mesh are connected and assembled and installed. At this time, the bottom bent metal mesh panel 156 and the front bent metal mesh panel 157 are installed so that the bottom surfaces thereof are separated from each other, and the vertical surfaces are substantially parallel to each other. The front side bent metal mesh panel 157 is installed in contact with the back surface portion 27 of the drainage channel 20. At this time, the back side bent metal mesh panel 156 and the front side bent metal mesh panel 157 are self-supporting, and the side side metal mesh is also leaned against the back side bent metal mesh panel 156 and the front side bent metal mesh panel 157, so it is necessary to support the metal mesh. It can be easily installed in a short time with a small number of people.

  Then, the space surrounded by the metal mesh panels 156 and 157 and the side metal mesh is filled with the cracking stones 23, 23,... To form a filter material layer (step A). As a result, a layer of filter material is formed between the raised portions of the back side bent metal mesh panel 156 and the front side bent metal mesh panel 157.

  Next, the upper surface of the layer of the filter material, the elevation surface portion of the back-side bent wire mesh panel 156, and the side wire mesh are covered with a sheet 37.

  Further, earth and sand are placed on the sheet 37 to form a back slope, and the construction is completed. Plants such as turf may be planted on the earth and sand.

  Since the drain structure according to the present embodiment has only one stage as compared with the drain structure according to the first embodiment, the construction is easier and can be performed in a shorter time. In addition, since there is no wire mesh on a part of the bottom surface and the layer of the filter material is formed directly on the foundation ground 21 at that part, the cost can be reduced and the construction can be performed more easily. The effects other than these differences are the same as those of the first embodiment. In addition, in this embodiment, since the elevation part of the back side bent metal-mesh panel 157 which hits a heel part is low, a capacity | capacitance becomes small. Therefore, in order to sufficiently lower the infiltrating surface in the levee body, it is necessary to install the back side bent wire mesh panel 157 as far as possible, but in that case, the amount of excavation and the amount of quarry stones 23, 23,. It takes extra time.

(Embodiment 5)
FIG. 14 shows a schematic side view of the drain structure according to the fifth embodiment. The drain structure according to this embodiment is obtained by connecting the bottom bent metal mesh panel 156 and the bottom bent metal mesh panel 157 with the bottom metal mesh 154 in the drain structure of the fourth embodiment. As a result, the strength of the drain structure is increased as compared with the fourth embodiment, but the construction takes a little extra time.

(Embodiment 6)
FIG. 15 shows a schematic side view of the drain structure according to the sixth embodiment. The drain structure according to the present embodiment is different from the drain structure according to the fourth embodiment in that an upper bent wire mesh panel 158 is installed above the back bent metal mesh panel 156, and the other points are the same as in the fourth embodiment. Since it is the same as, the differences will be explained.

  The drain structure of this embodiment is constructed in the same manner as in Embodiment 4 up to Step A. After this, the upper bent wire mesh panel 158 is installed above the back bent metal mesh panel 156 and on the filter material layer. The upper bent wire mesh panel 158 has the same configuration and shape as the rear bent wire mesh panel 156, and the upper bent wire mesh panel and the upper bent wire mesh panel 157 have a bottom surface extending from the vertical surface to the front side. It is installed so that the elevation part of 158 is substantially flush.

  Then, the split stones 23, 23,... Are placed on the bottom surface of the upper bent wire mesh panel 158. .. Are placed on at least the entire bottom surface of the upper bent wire mesh panel 158 and up to the height of the elevation in the vicinity of the elevation.

  Next, the sheet 37 covers the upper surface of the filter material layer, the upright portions of the back side bent metal mesh panel 157 and the upper bent wire mesh panel 158, and the side metal mesh. The filter material layer includes the filter material placed on the upper bent wire mesh panel 158.

  Further, earth and sand are placed on the sheet 37 to form a back slope, and the construction is completed. Plants such as turf may be planted on the earth and sand.

  Compared to the drain structure of the fourth embodiment, the drain structure of the present embodiment requires an extra cost and construction time for the installation of the upper bent wire mesh panel 158, but the height of the heel portion is increased and the capacity is increased. Therefore, the horizontal construction distance can be shortened. The other effects are the same as those of the fourth embodiment.

(Embodiment 7)
FIG. 16 shows a schematic side view of the drain structure according to the seventh embodiment. In the drain structure according to the present embodiment, the back-side bent wire mesh panel 159 has a length of about twice as long as the back-side bent wire mesh panel 156 of the drain structure according to the fourth embodiment in both the elevation part and the bottom part. Since the points are different and the other points are almost the same as those of the fourth embodiment, the different points will be described.

  In this embodiment, since the back side bent metal mesh panel 159 is longer than the front side bent metal mesh panel 157 in both the elevation part and the bottom part, the height of the heel part is higher than that in the fourth embodiment, and the horizontal construction distance is increased. As compared with the fourth embodiment. In addition, the cracked stones 23, 23,... Are stacked up to almost the same height as the upright portion in the vicinity of the upright bent wire mesh panel 159, but the stacked height decreases toward the front side. To go. It is preferable to place the cracked stones 23, 23,... On the upper portion of the bottom surface portion of the back side bent metal mesh panel 159 up to almost the same height as this elevation portion. The effects other than the aforementioned merits and demerits are the same as those in the fourth embodiment.

(Embodiment 8)
FIG. 17 shows a schematic side view of the drain structure according to the eighth embodiment. The drain structure according to the present embodiment is different from the drain structure of the seventh embodiment except that the front-side bent wire mesh panel 157 is removed, and the other points are the same as those of the seventh embodiment. Explain the points.

  In the present embodiment, the back side bent metal mesh panel 159 and the side side metal mesh are placed on the foundation ground 21, and the panel and the side wire mesh are connected and assembled by a coil. The space surrounded by the side wire mesh and the drainage channel 20 is filled with the split stones 23, 23,... To form a filter material layer (step A). As a result, a layer of filter material is formed between the vertical surface portion of the back-side bent wire mesh panel 159 and the drainage channel 20 installed at the lower end of the back slope. Other structures and construction methods are the same as those in the seventh embodiment.

  The drain structure of the present embodiment is inferior in strength because there is no front-side bent wire mesh panel 157 compared to the drain structure of the seventh embodiment, and the pressure applied to the back surface portion 27 of the drainage channel 20 is increased. This is advantageous. The other effects are the same as those of the seventh embodiment.

(Other embodiments)
The embodiments described so far are examples of the present invention, and the present invention is not limited to these examples. For example, the wire mesh that forms the side surface of each cage need not be a single piece, and a plurality of wire meshes may be connected. Or you may put the inner frame for reinforcement inside each cage. Each wire mesh is not limited to only one made of a welded wire mesh, and may be made of a panel made of expanded metal, a panel in which a diamond wire mesh is stretched on a steel bar frame, or the like.

  It is possible to form a long drain structure by arranging a plurality of front and rear wire meshes or elevations along the direction of the river flow, or a long drain with a wide width of the front and rear wire meshes or elevations. It is good also as a structure.

  The bottom intermediate wire mesh of Embodiments 1 to 3 is not limited to a weld wire mesh. A panel made of expanded metal, a panel in which a diamond wire mesh is stretched on a steel bar frame, or a panel in which a diamond wire mesh is stretched on a wire frame may be used.

  The coarse filter material is not limited to cracked stone, but any material such as gravel, crushed concrete (crushed concrete structure), rock crushed material, etc. that can be filled in the pot and can be used for water flow. Absent.

  The installation of the drainage channel 20 may not be before the piles are piled up. Further, a drain layer 42 as shown in FIG. 19 may be provided between the drainage channel 20 and the smoked drain part.

  As shown in FIG. 12, each saddle and each folded wire mesh panel are connected to the wire mesh at the bottom portion by a reinforcing member 59 so as not to fall down due to the pressure of the filter material filled with the back wire mesh 52 or the vertical surface portion. It is preferable. This reinforcing member 59 is preferably installed also on the front metal mesh 53 and the side metal mesh 55, 65, 75.

  In the construction of the above embodiment, the foundation ground is formed by excavating the levee body. However, a drain structure may be installed on a flat ground, and a slope may be formed by covering the soil with sand. . In addition, the drain structure is not limited to the embankment, and may be located anywhere as long as it is a slope such as a mountainside. For example, if installed on a mountainside, landslides can be prevented from occurring due to heavy rainfall. The construction method is the same as the method described in the above embodiment.

  Alternatively, after the back metal mesh 52 or the back side bent metal mesh panel is installed, a sheet may be applied to the inside of the back metal mesh or the vertical surface portion (side on which the bottom surface portion extends), and then a coarse filter material may be put.

  The sheet having flexibility and water permeability is not limited to a nonwoven fabric, and is a flexible sheet such as a sheet in which resin yarns are entangled to join each other, or a multilayer sheet having a strength retaining layer and a water permeable layer. Any sheet may be used as long as it has water permeability.

  The drainage channel 20 may have a configuration in which the back surface portion 27 is formed of porous concrete without providing the through holes 28,. In addition, the structure by which a part of back part 27 is formed with the porous concrete may be sufficient.

  As described above, since the drain structure according to the present invention can be easily installed on various slopes at low cost and can be drained reliably, it is useful as a drain structure for a bank.

2 is a schematic cross-sectional view of a drain structure according to Embodiment 1. FIG. FIG. 3 is a schematic side view of a wire mesh cage constituting the drain structure according to Embodiment 1. It is a figure of the metal-mesh group which comprises the 1st fence. It is a figure of the metal-mesh group which comprises the 2nd fence. It is a figure of the metal-mesh group which comprises a 3rd cage | basket. It is a perspective view of a drainage channel. It is a typical perspective view which shows the middle of construction of the drain structure which concerns on Embodiment 1. FIG. It is another schematic perspective view which shows the construction middle of the drain structure which concerns on Embodiment 1. FIG. It is another schematic perspective view which shows the middle of construction of the drain structure which concerns on Embodiment 1. FIG. It is a typical side view of the wire mesh cage which comprises the drain structure which concerns on Embodiment 2. FIG. It is a typical side view of the wire mesh cage which comprises the drain structure which concerns on Embodiment 3. It is a perspective view which shows the reinforcement member of a back metal mesh. 6 is a schematic cross-sectional view of a drain structure according to Embodiment 4. FIG. 6 is a schematic cross-sectional view of a drain structure according to Embodiment 5. FIG. 10 is a schematic cross-sectional view of a drain structure according to Embodiment 6. FIG. 10 is a schematic cross-sectional view of a drain structure according to Embodiment 7. FIG. FIG. 10 is a schematic cross-sectional view of a drain structure according to an eighth embodiment. It is a figure which shows the cross section of an embankment. It is typical sectional drawing of the drain structure concerning a comparative example.

Explanation of symbols

10 Dike body 12 Back slope (ground which is a slope)
20 Drainage channel 21 Foundation ground 22 Sediment 23 Cracked stone (coarse grain filter material)
27 Back portion 28 Through hole 31, 61, 71 First rod 32, 62, 72 Second rod 33, 63, 73 Third rod 37 Sheet 52 Rear wire mesh 53 Front wire mesh 156, 159 Back side bent wire mesh panel 157 Front side folded wire mesh panel 158 Upper folded wire mesh panel

Claims (11)

A drain structure embedded in the ground that is a slope and draining the permeated water that has penetrated into the ground into a drainage channel installed below the slope,
It is formed by a basket made of a wire mesh filled with a coarse filter material through which the permeated water passes, and has a smoked drain portion that guides the permeated water to the drainage channel,
The smoked drain part is configured by stacking a plurality of firewood and is covered with earth and sand,
The saddle is provided with a front wire mesh on the front side from the lower end of the slope toward the slope, a back wire mesh on the back side, and a bottom wire mesh on the bottom surface,
The front wire mesh, the back wire mesh and the bottom wire mesh are composed of self-supporting wire mesh panels,
Each of the front metal meshes of the plurality of baskets stacked is arranged on the front side from the lower end of the slope toward the slope as the bowl placed on the lower side,
A drain structure in which an upper surface side of the ridge is open, and a sheet having flexibility and water permeability is laid on the filter material on an upper surface other than a portion where another ridge is stacked.   The drain structure according to claim 1, wherein a part of the bottom wire mesh and the front wire mesh, and another part of the bottom wire mesh and the back wire mesh are integrally formed. A drain structure embedded in the ground that is a slope and draining the permeated water that has penetrated into the ground into a drainage channel installed below the slope,
The drainage channel is installed at the lower end of the slope,
From the lower end of the slope to the back side of the drainage channel, a back side bent wire mesh panel comprising a self-supporting wire mesh panel and having a bottom surface portion and an elevation surface portion is provided, and a bottom surface portion from the elevation surface to the front side. It is installed to extend,
A layer of a coarse filter material that allows the permeated water to pass from the drainage channel to the elevation of the back side bent wire mesh panel is formed,
A part of the coarse filter material layer is placed on the bottom surface of the back side bent wire mesh panel,
A drain structure in which an upright portion of the back-side bent wire mesh panel and an upper surface of the coarse filter material layer are covered with a flexible and water-permeable sheet. Between the drainage channel and the layer of the coarse filter material is a front side bent wire mesh panel comprising a self-supporting wire mesh panel and having a bottom surface portion and a vertical surface portion, and a bottom surface portion from the vertical surface portion to the back side. It is installed to extend,
The elevation surface portion of the front side folded wire mesh panel is sandwiched between the drainage channel and the coarse filter material layer,
The drain structure according to claim 3, wherein a part of the layer of the coarse filter material is placed on a bottom surface portion of the front-side bent wire mesh panel. The drainage channel has a back surface portion in contact with a layer of the coarse filter material or an elevation surface portion of the front side bent wire mesh panel,
The drain structure according to claim 3 or 4, wherein a through hole or a water permeable member through which the permeated water passes is provided in the back surface portion of the drainage channel. Above the back side bent wire mesh panel, an upper bent wire mesh panel made of a self-supporting wire mesh panel and provided with a bottom surface portion and an elevation surface portion is installed so that the bottom surface portion extends from the elevation surface to the near side,
A part of the coarse filter material layer is also placed on the bottom surface of the upper folded wire mesh panel, and the raised surface of the upper folded wire mesh panel is made of the flexible and water-permeable sheet. The drain structure according to any one of claims 3 to 5, which is covered. It is a construction method of a drain structure that is buried in the ground which is a slope and drains the permeated water that has penetrated into the ground into a drainage channel installed below the slope,
The drain structure has at least two ridges made of a self-supporting wire mesh panel and having an open upper surface, and the ridges are arranged on a front wire mesh arranged on the front side from the lower end of the slope toward the slope and on the back side. With a rear wire mesh,
A step of installing the first ridge on a substantially horizontal foundation ground existing below and inside the slope;
Filling the first basket with a coarse filter material;
A second ridge is placed on the first ridge, the front metal mesh of the second ridge is substantially parallel to the front metal mesh of the first ridge, and is directed from the lower end of the slope to the slope more than the front metal mesh of the first heel. The process of installing it so that it is located on the far side,
Filling the second basket with coarse filter material;
Laying a flexible and water permeable sheet on the exposed surface of the filter material filled in the first and second ridges;
A method of constructing a drain structure, comprising: covering the sheet with earth and sand. It is a construction method of a drain structure that is buried in the ground which is a slope and drains the permeated water that has penetrated into the ground into a drainage channel installed below the slope,
On the foundation ground that is substantially horizontal inside and below the slope, a back side folded wire mesh panel comprising a self-supporting wire mesh panel and having a bottom surface portion and an elevation surface portion is disposed on the front side from the lower end of the slope toward the slope. Installing the bottom surface portion so as to extend from the elevation surface portion;
A step of forming a layer of a coarse filter material above the foundation ground from the vertical surface of the back side bent wire mesh panel to the lower end of the slope, and
A step of covering the upright portion of the back-side bent wire mesh panel and the upper surface of the layer of the filter material with a flexible and water-permeable sheet;
A method of constructing a drain structure, comprising: covering the sheet with earth and sand.   The said process A is a construction method of the drain structure of Claim 8 which is a process of forming the layer of a coarse filter material to the said drainage channel set | placed at the lower end of a slope.   In the step A, a front-side folded wire mesh panel comprising a self-supporting wire mesh panel at the lower end of the slope and having a bottom surface portion and an elevation surface portion is installed so that the bottom surface portion extends from the elevation surface to the back side, The construction method of the drain structure according to claim 8, which is a step of forming a layer of a coarse filter material from the vertical surface portion of the side bent metal mesh panel to the vertical surface portion of the near side bent metal mesh panel.   After the step A, an upper bent wire mesh panel made of a self-supporting wire mesh panel and having a bottom surface portion and an elevation surface portion is provided above the back side bending wire mesh panel so that the bottom surface portion extends from the elevation surface portion toward the front side. The drain structure construction method according to claim 8, further comprising a step of installing and a step of placing a coarse filter material on a bottom surface portion of the upper folded wire mesh panel.

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