JP2018059337A - Bank protection mat, bank protection greening structure and bank protection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bank protection mat capable of achieving a simple and robust vegetative covered revetment, a bank protection greening structure and bank protection method.SOLUTION: The bank protection mat includes: a vegetation mat 3 to be laid over a slope face N; and a cylindrical body 4 constituted of a woven fabric of a mesh size which allows water to pass therethrough but not cement particles, the cylindrical body 4 being disposed in an upper portion of the vegetation mat 3. The vegetation mat 3 is constituted of a flexible net and a lawn mat. The cylindrical body 4 contains at least cement in an internal space with the end sealed.SELECTED DRAWING: Figure 1

Description

  The present invention, for example, revetments that can be used for greening of riversides, lakes, dam lakes, etc. (bank slopes, low water level laying of rivers, etc.) and prevention of surface collapse (revetment) at the same time. The present invention relates to a mat, a revetment greening structure and a revetment construction method.

  As a conventional vegetation revetment method on the slope of a river dike, there is a method of constructing a lawn mat grown on a field on the slope.

Japanese Patent Laid-Open No. 2002-4245

  However, the conventional method described above simply attaches the lawn mat to the slope, and the penetration depth of the lawn root into the slope is relatively shallow. There is a problem that it is easily peeled off and washed away, losing the revetment function at an early stage, and erosion of the slope due to running water tends to occur.

  The above problem is particularly noticeable immediately after the construction of the lawn mat. At the stage where the lawn mat was attached to the slope, it was attempted to fix the lawn mat to the slope with an anchor or the like. Because the shape retention strength of the lawn mat itself is weak, the anchoring part of the anchor etc. collapses when subjected to the action of running water, the lawn mat comes off from the anchor and eventually peels off from the slope. There is no.

  Then, the method of covering and fixing a net body on a lawn mat has been proposed (Patent Document 1). According to this method, it is possible to prevent the erosion of the slope due to running water or the like before the lawn root is fixed to the slope soil, and it is possible to improve the landscape of the slope. However, with the recent occurrence of abnormal weather such as so-called guerrilla heavy rain, the maximum flow velocity of water flowing through the river tends to increase, so it is desired to improve robustness. It is difficult to meet such demands.

  In terms of robustness, the concrete revetment method for constructing a heavy concrete structure is superior, but such a method has another problem that it requires heavy machinery for construction and becomes large-scale. .

  The present invention has been made in consideration of the above-described matters, and an object thereof is to provide a revetment mat, a revegetation greening structure, and a revetment method capable of realizing a simple and robust vegetation revetment.

  In order to achieve the above object, a revetment mat according to the present invention is a woven fabric having a scale that allows water to pass through and prevents cement particles from passing through one side of a vegetation mat composed of a flexible net and a lawn mat. The cylindrical body comprised by these is mounted | worn (Claim 1).

  In the above revetment mat, the cylindrical body has at least a flow channel portion for circulating cement and a through-hole through which an anchor pin can pass, and the through-hole avoids the flow channel portion. (Claim 2).

  In order to achieve the above object, a revegetation greening structure according to the present invention includes a vegetation mat laid on a slope and a scale that is disposed on the upper side of the vegetation mat and allows water to pass therethrough and does not pass cement particles. The vegetation mat is composed of a flexible net and a lawn mat, and the tubular body is closed at its end and has at least cement in its internal space. Is accommodated (claim 3).

  In order to achieve the above object, the revetment method according to the present invention is laid on a slope and arranged on the upper side of a vegetation mat composed of a flexible net and a lawn mat, allowing water to pass through and passing cement particles. At least cement is accommodated in a cylindrical body constituted by a woven fabric having a texture that is not allowed.

  In the present invention, a revetment mat, a greening structure for revetment, and a revetment method capable of realizing a simple and robust vegetation revetment are obtained.

  That is, in the revetment mat, the revetment greening structure and the revetment construction method according to the claims of the present application, the vegetation mat exhibits the greening function of the slope, and the method is performed by the cylindrical body containing cement in the internal space. A revetment greening structure that exhibits the revetment function of the surface (structural function necessary for preventing the slope surface from collapsing) and ensures robustness can be obtained.

  In addition, large construction machines such as heavy machinery are indispensable for the conventional concrete revetment work, which is a large-scale construction. However, it is possible to easily construct the revetment greening structure that does not require most of such large construction machines.

  In the revetment mat of the invention according to claim 2, for example, when the revetment mat is installed on the slope, an anchor pin is placed in the through-hole of the cylindrical body, so that cement is applied to the flow path portion. When filled, the flow path portion can be prevented from being loosened largely to the valley side due to the weight of the cement.

  Moreover, in the revetment method of the invention which concerns on Claim 4, since only excess water can be discharged | emitted from each cylindrical body which accommodated cement and water, the intensity | strength of the greening structure for revetment constructed after solidification of cement Not only can it be prevented from lowering, and thus increase the strength, but the cement until it is filled (contained) in the cylindrical body should be in the form of a cement fluid that contains at least water and cement and has an increased water-cement ratio. If the fluidity is increased and the speed at which this cement fluid is filled into the cylindrical body is increased, the construction can be shortened.

It is a perspective view which shows roughly the structure of the greening structure for revetment constructed | assembled by the revetment construction method which concerns on one embodiment of this invention. It is a top view which shows roughly the structure of the said greening structure for bank protection. (A) And (B) is the perspective view and top view which show schematically the structure of the mat | matte for revetment concerning one embodiment of this invention. It is explanatory drawing which shows the modification of the said revetment construction method. It is explanatory drawing which shows the other modification of the said revetment method. (A) And (B) is explanatory drawing which shows the suitable example and modification of the said revetment mat.

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

  As shown in FIG. 1, a revetment mat (hereinafter referred to as the main mat) 1 according to the present embodiment has a revetment greening structure (hereinafter referred to as the main structure) 2 on a slope N such as a river dike. It is used for the revetment construction method (hereinafter referred to as the main construction method) to be constructed. As shown in FIGS. 2 (A) and (B), the vegetation mat 3 and the scale that does not allow cement particles to pass through are used. And a cylindrical body 4 mounted on one side of the vegetation mat 3.

  The vegetation mat 3 is formed by integrating a lawn mat with a flexible net, and is configured to have a rectangular shape with a length of 3 m and a width of 1 m in a plan view, for example.

Here, it is preferable to use, for example, a geotextile net (geotextile) as the flexible net. This geotextile net is made of a high-tensile material such as polyethylene, polyester, aramid, glass fiber, etc., and has a tensile strength of about 500 kg / m to 8 t / m and a weight of 200 g / m ^{2 to} 300 g / m. ^2. It has the characteristics of being strong and having high tension despite being lightweight. The mesh of the flexible net may be, for example, 7 mm to 30 mm.

  And the vegetation mat 3 which consists of a flexible net | network and a lawn mat is manufactured as follows, for example. In other words, a flexible net is laid on the field, a lawn mat grown separately on the net is laid on the net, and the lawn mat can be attached when the root of the lawn mat is entangled with the flexible net. The flexible net, that is, the vegetation mat 3 is peeled off from the field.

  According to this manufacturing method, the vegetation mat 3 with high shape retention property in which the strong surface layer root of the lawn mat is firmly entangled with the flexible net is obtained. If the vegetation mat 3 is laid on the slope N and the vegetation mat 3 (flexible net) is fixed by a fixing member such as a self-piercing anchor or a reinforcing bar insertion anchor, the lawn mat is firmly attached to the flexible net. Therefore, the lawn mat can be substantially firmly attached to the slope N through the flexible net, and the lawn mat is firmly attached to the slope N over time. Will be rooted in. On the other hand, if the anchor pin that fixes the vegetation mat 3 to the slope N is inserted into the surface layer portion of the slope N, the slope reinforcement effect by the anchor pin is exhibited and the slope N can be suitably prevented from collapsing.

  Therefore, when the vegetation mat 3 is used for a vegetation revetment on a river slope, for example, even if the river increases immediately after construction, the vegetation mat 3 is not easily peeled off by running water, In addition to being excellent on the landscape, erosion of the slope due to running water is effectively prevented.

  As shown in FIGS. 2 (A) and 2 (B), the cylindrical body 4 includes a longitudinal flow path portion 5 extending in the longitudinal direction of the vegetation mat 3 as a flow path portion for circulating the cement fluid, And a horizontal flow path portion 6 that extends to the left and right (or in a direction perpendicular to the vertical flow path portion 5) in a state of communicating with the flow path portion 5. Moreover, the cylindrical body 4 has an overhanging portion 7 that protrudes from the edge of the horizontal flow path portion 6, and the overhanging portion 7 is provided with a through hole 8 through which an anchor pin (not shown) can pass. That is, the through hole 8 is provided at a position avoiding the flow path portions 5 and 6 in plan view.

  The woven fabric constituting the cylindrical body 4 uses carbon fiber or other fibers having a high tensile strength, and the cement particle diameter is 20 μm, whereas the grain size is approximately 0.001 μm (1 nm) (cement grain It is preferable to use a woven fabric having a mesh size of about 1/20000 of the diameter.

  And attachment of the cylindrical body 4 with respect to the single side | surface of the vegetation mat 3 can be performed by crimping | compression-bonding, a stitch | suture, the connection by an appropriate member, etc., for example, this mat 1 after formation is the state packed in roll shape, for example It can be transported by.

  Next, the construction method using the mat 1 will be described.

  (1) First, a plurality of main mats 1 are laid out on a slope N whose surface has been leveled in advance.

  At this time, the book mats 1 are arranged so that the horizontal flow path portions 6 are along the contour lines, and the book mats 1 are fixed to the slope N by a fixing member such as an anchor pin. The mat 1 can be laid on the slope N by using human power or a tow truck.

  (2) Subsequently, the anchor pins (not shown) are connected so that the end portions of the flow path portions 5 and 6 of the cylindrical body 4 of the adjacent mat 1 are connected to each other and penetrate the through hole 8 of the cylindrical body 4. (See FIG. 3).

  Here, the end portions of the flow passage portions 5 and 6 of the cylindrical body 4 can be connected to each other in a state where one of the end portions is inserted into the other, or an appropriate connecting tube (for example, a vinyl chloride tube). However, in any case, it is desirable to prevent the cement fluid that will flow through the cylindrical body 4 in a later step from leaking out from the connecting portion.

  In addition, when the anchor pin is placed in the through hole 8, when the lateral flow path portion 6 is filled with the cement fluid in the subsequent process, the lateral flow path portion 6 is largely loosened to the valley side due to the weight of the cement fluid. It is only necessary to place anchor pins within a range where it is desired to prevent this loosening, and it is not always necessary to place anchor pins in all the through holes 8.

  (3) Of the end portions of the flow passage portions 5 and 6 of the cylindrical body 4 of each book mat 1, the end portions that are not connected to the tubular body 4 of the other book mat 1 are closed, and at this time, toward the mountain side. At least one end that opens is left unblocked.

  The end portions of the flow path portions 5 and 6 can be closed by, for example, suturing, crimping, or binding using an appropriate member or device. In addition, this blockage may be performed at the site, or the above-described blockage operation is performed at the site by arranging the mat 1 in which specific end portions of the flow path portions 5 and 6 are previously blocked as necessary. You may make it save the effort which performs.

  In addition, in this embodiment, it is only the main mat 1 located in the outer peripheral part (outermost part) among the plurality of the main mats 1 arranged to have the flow path portions 5 and 6 whose end portions are closed. .

  (4) In (3) above, the cement fluid is poured from the end portions of the flow path portions 5 and 6 left without being blocked, and filled into the respective cylindrical bodies 4.

  Cement fluid is easy to adjust to the unevenness of slope N, W / C 100% or more, a flow fluid of about 1000 mm, and a highly fluid cement milk (consisting of water and cement and optionally a cement admixture) or Mortar (containing at least water, cement and fine aggregate). And in this embodiment, as shown in FIG. 1, the cement milk as a cement fluid produced | generated by mixing water and cement is a pump for pumping (for example, mortar pumping which has the discharge capability of 30L or more per minute). For example, the inside of the hose 11 is pumped by the pump 10 and is filled into the cylindrical body 4 from the nozzle 12 at the tip of the hose 11.

  (5) Waiting for the excess water to be automatically discharged to some extent by gravity from each cylindrical body 4 containing the cement fluid (the cylindrical body 4 is reduced), the cement fluid is again cylindrical. The procedure of filling the body 4 is repeated until each cylindrical body 4 is not reduced.

  That is, as described above, the cylindrical body 4 is made of a woven fabric having a scale that allows water to pass but does not allow cement particles to pass through. Therefore, excess water is discharged from each cylindrical body 4 containing the cement fluid. However, the cement particles remain in the cylindrical body 4.

  Here, the cement component is strongly alkaline with a pH of 12.5, and in order to suppress the influence on the vegetation caused by the excess water discharged from the cylindrical body 4, it is preferable to neutralize it. For example, the neutralizing agent can be mixed with the cement fluid, supported on the cylindrical body 4, or sprayed on the slope N.

  (6) If the cement fluid accommodated in the internal space of each cylindrical body 4 is solidified, the structure 2 is built on the slope N (see FIG. 1). The construction method is completed.

  The structure 2 constructed by the construction method using the mat 1 exhibits a greening function of the slope N by the vegetation mat 3, and cement is contained in the internal space (the cement fluid is solidified in the internal space). The cylindrical body 4 exhibits the revetment function of the slope N (structural function necessary for preventing the collapse of the slope surface) and secures the robustness.

  Further, in the present construction method in which only the surplus water can be discharged from each cylindrical body 4 containing the cement fluid, the strength of the present structure 2 constructed after the cement fluid is solidified can be prevented from being lowered, and thus increased in strength. Not only can be achieved, the water-cement ratio of the cement fluid up to filling (accommodating) in the cylindrical body 4 is increased to increase its fluidity, and the cylindrical fluid 4 is filled with the cement fluid. If the speed is increased, construction can be shortened.

  In addition, large construction machines such as heavy machinery are indispensable for conventional concrete revetment works, and this construction method requires almost all such large construction machines, and this structure 2 is easily constructed. be able to.

Furthermore, in this construction method, the cement fluid remaining in the cylindrical body 4 after the discharge of excess water can be made to have a low water cement ratio with a W / C of 50% or less, and its four-week compressive strength is if so (18N / mm 2 in the conventional wet mortar ^spraying) to 30 N / mm having ² or more, which can also be used as a pressure receiving plate (pressure receiving plate) in the anchor Engineering (lock bolt Engineering or ground anchor Engineering) and Become. And when using this construction method and an anchor method together in this way, a construction period shortening drastically can be achieved rather than performing both separately.

  In general, it is considered that a frame having a continuous frame and expected to have bending rigidity has a certain degree of suppressing function against surface slip on the slope N. From this viewpoint, the structure 2 Since the frame formed by the cylindrical body 4 is continuous and can be expected to have bending rigidity, it also exhibits a function of suppressing surface slippage on the slope N.

  It should be noted that the present invention is not limited to the above-described embodiment, and can be variously modified and implemented without departing from the gist of the present invention. For example, the following examples can be given.

  The mat 1, the structure 2, and the construction method are not limited to the slope N, and may be used and constructed on a flat ground or the like.

  The vegetation mat 3 is not limited to a lawn mat that is integrated with a flexible net in advance. For example, the vegetation mat 3 is constructed by laying a lawn mat on-site and then stretching the flexible net from the upper side. It may be done. In this case, the cylindrical body 4 may be integrated with the flexible net in advance, or both may be integrated on site.

  A water reducing agent may be mixed in the cement fluid contained in the tubular body 4. Moreover, you may mix admixtures, such as an aramid fiber and a nano cellulose, with a cement fluid, and the tensile strength of the frame of this structure formed with the cylindrical body 4 improves dramatically in this case.

  The number, arrangement, thickness, and interval (pitch) of the vertical flow path portions 5 and the horizontal flow path portions 6 provided in the cylindrical body 4 can be variously changed. By changing these elements, the degree of erosion prevention of the surface layer (Corresponding depth) changes. Further, for example, the horizontal flow path portion 6 may not be provided, and the cylindrical body 4 may have only the vertical flow path portion 5. In this case, the vertical flow path portion 5 may have a zigzag shape or the like. Moreover, if the shape of the cylindrical body 4 is appropriately modified, it can be easily used in various civil engineering and building fields such as retaining walls and earth retaining dams.

  A concrete containing at least water, cement, and coarse aggregate may be used as the cement fluid. Moreover, in the said embodiment, although the cement accommodated in the cylindrical body 4 is made into the form of the cement fluid containing at least water and cement, it is not restricted to this, When accommodating in the cylindrical body 4 For example, dry powder cement, dry mortar (a mixture of granular sand, vermiculite, pearlite (pumice), etc.) and granular cement. You may make it harden a cement by natural water absorption and moisture absorption by watering or raining etc. to the cylindrical body 4 later.

  In this method, in the above steps (4) and (5), an operation of repeatedly filling the cylindrical body 4 with the cement fluid is performed. To save such trouble, for example, as shown in FIG. In addition, in (3) above, for example, a cylindrical storage part 13 made of a water-impermeable material is connected to the ends of the flow path parts 5 and 6 left without being blocked, After the cement fluid is spread over the entire cylindrical body 4, the cement fluid is stored in the storage section 13, and the cylinders are transferred from the storage section 13 according to the reduction (discharge of excess water) of each cylindrical body 4. The cement fluid may be supplied to the body 4, and in this way, the number of times of the cement fluid filling operation can be reduced, and therefore only once.

  In the above embodiment, in order to arrange the horizontal flow path portion 6 along the contour line as shown in FIG. 3, in the example shown in FIGS. 2 (A) and 2 (B), the horizontal flow path portion 6 is replaced with the vertical flow path portion. However, the present invention is not limited to this. For example, as shown in FIG. 5, the lateral flow path portion 6 is valley-side by an angle θ from the direction along the contour line (the direction perpendicular to the vertical flow path portion 5). In this case, it is possible to more easily fill the lateral flow path portion 6 with cement (cement fluid). The angle θ is preferably around 0 to 45 degrees. When the angle θ is less than 0 degrees and the horizontal flow path portion 6 is inclined toward the mountain side, it becomes difficult to fill the lateral flow path portion 6 with cement. When the angle θ is greater than 45 degrees, the cross flow path portion 6 is directed toward the valley side. Slope is steep, and sedimentation and small tumbling stones can be prevented by the horizontal channel part 6 This is because the vegetation base thus formed is formed in a step shape, and the effect of facilitating the growth of the plant in the step is greatly impaired.

  In the example shown in FIG. 1, cement milk (cement fluid) is poured into the cylindrical body 4 using the pump 10 for pumping. However, the present invention is not limited to this, for example, cement milk (cement milk) on the mountain side of the cylindrical body 4. A fluid) may be created, and cement milk may be poured into the cylindrical body 4 by its own weight.

  The cylindrical body 4 in the above embodiment may have a single structure by woven cloth, but as shown in FIG. 6A, it has a double or more multiple structure (triple structure in the illustrated example). In this case, the inner woven fabric 14 swells with the expansion of the cement fluid, etc., and the texture tends to expand, but the outer woven fabric 14 is less susceptible to such influences. In addition, the pressure is dispersed, and the scale of the entire cylindrical body 4 does not increase, and only excess water can be more reliably removed from the scale of the cylindrical body 4. Further, even when there is a protrusion on the slope N or the like, since the possibility that the outer woven fabric 14 is damaged by the protrusion is low to the inner woven fabric 14 is also low. As a whole, it becomes difficult to break. In FIG. 6 (A), a woven fabric 14 that is layered three times and a woven fabric 14 that is layered three times separately are stacked on the front and back, and the stacked end portions are stitched together to form a tubular shape. An example of forming the body 4 is shown.

  In the cylindrical body 4 in the above embodiment, a linear core material (not shown) such as a PC steel wire or a net-like core material 15 (see FIG. 6B) is provided to improve strength. You may make it show. FIG. 6B shows an example in which the net-like core material 15 is sandwiched between the ends of the woven fabric 14 that are layered three times as in the example shown in FIG. 6A. .

  A reinforcing material such as steel fiber may be mixed into the cement fluid to obtain the effect of improving the strength of the cylindrical body 4 after curing. Moreover, you may make it the crack prevention effect of the cylinder 4 after hardening by mix | blending a hardening retarder with a cement fluid, and lowering | curing speed.

  In the above embodiment, the anchor pin is driven in the through hole 8 provided in the overhanging portion 7 of the cylindrical body 4. Instead of this configuration, or in addition to this configuration, the overhanging portion 7 is not used. An anchor pin may be placed on the main body of the tubular body 4. In this case, if the anchor pin is directly placed on the main body of the tubular body 4 after the cement fluid is accommodated and the excess water is discharged to some extent and the cement fluid is completely solidified, It can be easily performed without receiving a large resistance from the cement fluid, and after the cement fluid in the cylindrical body 4 is solidified, the cylindrical body 4 and the anchor pin are firmly integrated. Further, the inventors have confirmed that leakage of cement fluid from the cylindrical body 4 can be prevented even when such anchor pins are placed.

  Needless to say, the modification examples given in the present specification may be appropriately combined.

DESCRIPTION OF SYMBOLS 1 Revetment mat 2 Revegetation greening structure 3 Vegetation mat 4 Cylindrical body 5 Longitudinal flow path part 6 Horizontal flow path part 7 Overhang part 8 Through hole 9 Connecting pipe 10 Pump for pump 11 Hose 12 Nozzle 13 Storage part N Slope

Claims (4)

  A cylindrical body made of a woven fabric having a texture that allows water to pass through and cement particles to pass through is attached to one side of a vegetation mat made of a flexible net and a lawn mat. Revetment mat.   The cylindrical body has at least a flow channel portion for circulating cement and a through hole through which an anchor pin can pass, and the through hole is provided at a position avoiding the flow channel portion. Item 1. A revetment mat according to item 1.   A vegetation mat laid on a slope, and a tubular body that is arranged on the upper side of the vegetation mat and is configured by a woven fabric having a texture that allows water to pass but does not allow cement particles to pass therethrough. Is constituted by a flexible net and a lawn mat, and the cylindrical body is closed at the end, and at least cement is accommodated in the internal space thereof. At least in a cylindrical body constituted by a woven fabric laid on the slope and arranged on the upper side of the vegetation mat constituted by a flexible net and a lawn mat, having a scale that allows water to pass and does not allow cement particles to pass A revetment method characterized by containing cement.

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