JP6811469B2 - Surface layer collapse prevention mat, surface layer collapse prevention combined greening structure and surface layer collapse prevention combined greening method - Google Patents

Description

The present invention relates to, for example, a surface layer collapse prevention mat, a surface layer collapse prevention combined greening structure, and a surface layer collapse prevention combined greening method capable of simultaneously greening a slope and preventing surface collapse.

As a conventional slope reinforcement method, it is possible to prevent vegetation from eroding the slope surface layer (layer with a depth of 0 m to 2 m), and to prevent the slope surface layer from collapsing (see Patent Document 1). The on-site spraying method frame construction (see Patent Document 2) is known.

JP-A-2002-121739 Japanese Unexamined Patent Publication No. 2004-197553

The vegetation mat work, in which the vegetation mat is laid on the slope, is excellent in that it can be performed relatively easily, and is often used for the purpose of preventing erosion of the slope surface layer due to weathering or the like. However, vegetation is laid on a slope with low stability where not only surface erosion but also collapse is a concern, and vegetation mats that cannot be expected to exert structural functions that can prevent the collapse are laid. It is difficult to apply matting.

On the other hand, on-site spraying formwork, which forms the formwork by spraying mortar and concrete on the formwork installed on the slope, can prevent the surface layer of the slope from collapsing, but it takes time and effort to install the formwork. , There is a problem that the construction becomes large-scale.

The present invention has been made in consideration of the above-mentioned matters, and an object thereof is a mat for preventing surface collapse, which can achieve labor saving in construction while simultaneously trying to green the slope and prevent surface collapse. It is an object of the present invention to provide a greening structure for preventing surface collapse and a greening method for preventing surface collapse.

In order to achieve the above object, the surface layer collapse prevention mat according to the present invention is a tubular body made of a woven cloth having a mesh that allows water to pass through and cement particles to pass through on one side of the vegetation mat . At least the flow path portion of the tubular body for circulating cement is mounted in a state where the cement is not filled (claim 1).

In preventive mat the surface collapse, the tubular body, said channel portion, and a through-hole anchor pin can penetrate the through hole is provided in a position avoiding the channel portion It may be (Claim 2).

In order to achieve the above object, in the surface layer collapse prevention combined greening structure according to the present invention, a plurality of surface layer collapse prevention mats according to claim 1 or 2 are laid side by side on the ground, and the adjacent surface layer collapse prevention mats are laid. The flow paths of the tubular body are connected to each other in a state in which the insides communicate with each other, and at least cement is housed in the internal space (claim 3).

To achieve the above object, the surface collapse prevention combined greening method according to the present invention, in the flow path portion of the tubular body of shallow landslides antistatic mat according to claim 1 or 2 laid on the ground It accommodates pouring at least cement (claim 4).

In the present invention, a mat for preventing surface collapse, a greening structure for preventing surface collapse, and a greening method for preventing surface collapse can be achieved while simultaneously greening the slope and preventing surface collapse. Is obtained.

That is, in the surface layer collapse prevention mat, the surface layer collapse prevention combined greening structure, and the surface layer collapse prevention combined greening method of the inventions according to the claims of the present application, the vegetation mat exerts a slope greening function, and cement is used in the internal space thereof. A greening structure that also prevents surface collapse can be obtained by the tubular body containing the above, which exerts the structural function necessary for preventing the collapse of the surface layer of the slope.

Moreover, although a large amount of labor is required to install the formwork in the conventional on-site spraying method frame work, it is possible to easily construct the above-mentioned surface layer collapse prevention combined greening structure that does not require the installation of such formwork.

In the surface layer collapse prevention mat of the invention according to claim 2, for example, when the surface layer collapse prevention mat is installed on a slope, if an anchor pin is driven into a through hole of a tubular body, a flow path can be obtained. When the portion is filled with cement, it is possible to prevent the flow path portion from loosening significantly toward the valley side due to the weight of the cement.

Further, in the surface layer collapse prevention and greening method of the invention according to claim 4, since only excess water can be discharged from each tubular body containing cement and water, the structure constructed after the cement is solidified. Not only can the strength of the cement be prevented from decreasing, and the strength of the cement can be increased, but the cement until it is filled (contained) in the tubular body should be in the form of a cement fluid containing at least water and cement and having an increased water-cement ratio. If the fluidity is increased and the speed at which the cement fluid is filled into the tubular body is increased, it is possible to shorten the construction time.

It is a perspective view which shows typically the structure of the surface layer collapse prevention combined greening structure constructed by the surface layer collapse prevention combined greening method which concerns on one Embodiment of this invention. It is a top view which shows roughly the structure of the greening structure which also serves as surface collapse prevention. (A) and (B) are perspective views and plan views schematically showing the configuration of a surface layer collapse prevention mat according to an embodiment of the present invention. It is explanatory drawing which shows the modification of the said greening method for preventing surface collapse. It is explanatory drawing which shows the other modification of the said greening method for preventing surface collapse. (A) and (B) are explanatory views showing a preferable example and a modification of the surface layer collapse prevention mat.

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

As shown in FIG. 1, the surface layer collapse prevention mat (hereinafter referred to as the present mat) 1 according to the present embodiment has a surface layer collapse prevention combined greening structure (hereinafter referred to as the present structure) 2 on the slope N. It is used for the surface layer collapse prevention combined greening method (hereinafter referred to as this method) to be constructed, and as shown in FIGS. 2A and 2B, the vegetation mat 3 and water are passed through and cement particles are passed through. It is composed of a woven fabric having a mesh that does not allow the vegetation mat 3, and includes a tubular body 4 mounted on one side of the vegetation mat 3.

The vegetation mat 3 is formed by superimposing a vegetation sheet on the lower surface of the net, and is configured to have a rectangular shape of, for example, 2 m in length and 1 m in width in a plan view.

Here, as the material of the net, when it is necessary to turn it into soil over the years, we would like to use natural fibers or biodegradable plastic fibers to semi-permanently secure the flow and erosion prevention effect of the surface soil. In that case, fibers such as polyethylene and nylon may be used.

The vegetation sheet is a thin cotton-like sheet such as rayon on which a vegetation base material such as vegetation seeds, fertilizer, and soil conditioner is supported. The thin cotton-like sheet is preferably sheet-like thin cotton (not meaning cotton, but thin cotton-like material), but may be something like non-woven fabric or paper. This thin cotton-like sheet has enough strength not to hinder the sprouting and rooting of plants, and the average thickness thereof is set to 0.1 to 10 mm, preferably 0.5 to 5 mm to prevent erosion. It is possible to make it easier for plants to take root in the ground while having a function.

Then, the net and the vegetation sheet are integrated in a laminated state to form the vegetation mat 3, and the integration may be performed, for example, by entwining the fibers of the thin cotton-like sheet of the vegetation sheet with the net. , The net and the vegetation sheet may be adhered with a small amount of water-soluble adhesive, or both means may be used in combination. As a method of entwining the fibers of the thin cotton-like sheet with the net, a method of entwining the fibers of the thin cotton-like sheet with the net by passing the net and the vegetation sheet between the rollers in a laminated state and applying pressure, or the thin cotton-like sheet side A method is conceivable in which the fibers of the thin cotton-like sheet are raised toward the net side and entangled with the net by blowing air from the net side or sucking air from the net side.

The tubular body 4 has a vertical flow path portion 5 extending in the longitudinal direction of the vegetation mat 3 and a vertical flow path portion 5 communicating with the vertical flow path portion 5 as a flow path portion for circulating the cement fluid, toward the left and right sides thereof. It has a horizontal flow path portion 6 extending (or in a direction orthogonal to the vertical flow path portion 5). Further, the tubular body 4 has an overhanging portion 7 protruding from the edge of the lateral flow path portion 6, and the overhanging portion 7 is provided with a through hole 8 through which an anchor pin (not shown) can penetrate. That is, the through hole 8 is provided at a position avoiding the flow path portions 5 and 6 in a plan view.

Fibers with high tensile strength such as carbon fibers are used for the woven fabric constituting the tubular body 4, and while the cement particle size is 20 μm, the mesh size (cement grains) is approximately 0.001 μm (1 nm). It is preferable to use a woven fabric having a mesh size of about 1/20000 of the diameter).

The tubular body 4 can be attached to one side of the vegetation mat 3 by, for example, crimping, suturing, connecting with an appropriate member, or the like, and the formed mat 1 is packed in a roll shape, for example. It can be carried at.

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

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

At this time, each mat 1 is arranged so that the lateral flow path portion 6 follows the contour line, and each mat 1 is 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 human power or by using a tow truck or the like.

(2) Subsequently, an anchor pin (not shown) is shown so as to connect the ends of the flow paths 5 and 6 of the tubular body 4 of the adjacent mat 1 and to penetrate the through hole 8 of the tubular body 4. (See Fig. 3).

Here, the ends of the flow paths 5 and 6 of the tubular body 4 can be connected to each other with one of the ends inserted into the other, or an appropriate connecting pipe (for example, a vinyl chloride pipe). 9 or the like can be used, but in any case, it is desirable that the cement fluid that will be circulated in the tubular body 4 in a later step does not leak from the connecting portion.

Further, in the placement of the anchor pin in the through hole 8, when the lateral flow path portion 6 is filled with the cement fluid in a later step, the lateral flow path portion 6 is largely loosened toward the valley side due to the weight of the cement fluid. It is necessary to drive the anchor pins within the range in which the slack is to be prevented, and it is not always necessary to drive the anchor pins in all the through holes 8.

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

The ends of the flow path portions 5 and 6 can be closed by, for example, suturing, crimping, or binding using an appropriate member or device. This closing may be performed at the site, or by arranging the mat 1 in which the specific ends of the flow paths 5 and 6 are closed in advance as necessary, the closing operation is performed at the site. You may try to save the trouble of doing.

In this embodiment, only the mat 1 located on the outer peripheral portion (outermost) of the plurality of mats 1 having the flow path portions 5 and 6 whose ends are closed is provided. ..

(4) In the above (3), the cement fluid is poured from the ends of the flow path portions 5 and 6 left unobstructed and filled into each tubular body 4.

The cement fluid is extremely fluid cement milk (consisting of water, cement and, if necessary, a cement admixture) with a W / C of 100% or more and a flow value of about 1000 mm, which easily adapts to the unevenness of the slope N. Mortar (including at least water, cement and fine aggregate). Then, in the present embodiment, as shown in FIG. 1, cement milk as a cement fluid produced by mixing water and cement is pumped by a pump (for example, a mortar pump having a discharge capacity of 30 L or more per minute). The inside of the hose 11 is pumped by the pump) 10, and the inside of the tubular body 4 is filled from the nozzle 12 at the tip of the hose 11.

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

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

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

(6) When the cement fluid contained in the internal space of each tubular body 4 solidifies, the structure 2 is in a state of being built on the slope N (see FIG. 1). This method is completed.

In the structure 2 constructed by this method using the mat 1, the vegetation mat 3 exerts a greening function on the slope N, and cement is contained in the internal space (the cement fluid is solidified in the internal space). The tubular body 4 exerts the structural function necessary for preventing the surface layer of the slope N from collapsing.

Further, in this construction method in which only excess water can be discharged from each tubular body 4 containing the cement fluid, the strength of the structure 2 constructed after the solidification of the cement fluid is prevented from being lowered, and the strength is increased. Not only can it be planned, but the water-cement ratio of the cement fluid until it is filled (accommodated) in the tubular body 4 is increased to increase its fluidity, and the cement fluid is filled in the tubular body 4. If the speed is increased, it will be possible to shorten the construction time.

Moreover, the conventional on-site spraying method frame construction requires a great deal of labor to install the formwork, but this construction method does not require the installation of such formwork, and the structure 2 can be easily constructed. ..

Further, in this method, the cement fluid remaining in the tubular body 4 after the surplus water is discharged can be made to have a low water cement ratio of W / C of 50% or less, and the four-week compressive strength is increased. 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. When this method and the anchor method are used together in this way, it is possible to achieve a significant reduction in the construction period as compared with the case where both methods are used individually.

Further, it is generally considered that a frame having a continuous frame and expected flexural rigidity has a function of suppressing the surface slip of the slope N to some extent, but from such a viewpoint, the present structure 2 Since the frame formed by the tubular body 4 is continuous and can be expected to have flexural rigidity, it also exerts a function of suppressing surface slip on the slope N.

Needless to say, 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 flat ground or the like.

The vegetation mat 3 is not limited to the one obtained by polymerizing a vegetation sheet on the lower surface of the net, and may be in the form of a net or a thin sheet, for example.

A water reducing agent may be mixed with the cement fluid contained in the tubular body 4. Further, an admixture such as aramid fiber or nanocell roll may be mixed in the cement fluid, and in this case, the tensile strength of the frame of the present structure formed by the tubular body 4 is dramatically improved.

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

As the cement fluid, concrete containing at least water, cement and coarse aggregate may be used. Further, in the above embodiment, the cement contained in the tubular body 4 is made to take the form of a cement fluid containing at least water and cement, but the present invention is not limited to this, and when the cement is contained in the tubular body 4. In the form of, for example, dry powder cement, dry mortar (a mixture of granular sand, vermiculite, pearlite (light stone) and other aggregates), and granular cement, the cement is stored in the tubular body 4. Later, the cement may be hardened by natural water absorption / moisture absorption due to watering or rainfall on the tubular body 4.

In this method, in the above steps (4) and (5), the cement fluid is repeatedly filled into the tubular body 4, but in order to save such trouble, for example, as shown in FIG. In (3) above, for example, a tubular storage portion 13 made of an impermeable material is connected to the ends of the flow path portions 5 and 6 left unobstructed, and the storage portion 13 is used. After the cement fluid is distributed throughout the tubular body 4, the cement fluid is stored in the storage unit 13, and the cylinder is discharged from the storage unit 13 according to the reduction (exhaust of excess water) of each tubular body 4. The cement fluid may be supplied to the body 4, and in this way, the number of times of filling the cement fluid can be reduced, and by extension, it can be performed only once.

In the above embodiment, in order to arrange the transverse flow path portion 6 along the contour lines as shown in FIG. 3, in the examples shown in FIGS. 2A and 2B, the transverse flow path portion 6 is arranged in the vertical flow path portion. It is extended in the direction orthogonal to 5, but is not limited to this, and as shown in FIG. 5, for example, the lateral flow path portion 6 is on the valley side by an angle θ from the direction along the contour line (the direction orthogonal to the vertical flow path portion 5). In this case, the lateral flow path portion 6 can be more easily filled with cement (cement fluid). The angle θ is preferably around 0 to 45 degrees. When the angle θ is set to less than 0 degrees and the lateral flow path portion 6 is tilted toward the mountain side, it becomes difficult to fill the lateral flow path portion 6 with cement. When the angle θ is larger than 45 degrees, the lateral flow path portion 6 is directed to the valley side. The slope becomes steep, and the effect of suppressing sediment runoff and small boulders obtained by the lateral flow path 6 and the small step effect (accumulation by blocking flying seeds, leaves, runoff sediment from the slope mountain side, etc.) This is because the vegetation base is formed in small steps, and the effect of facilitating the growth of plants in the small steps) is significantly impaired.

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

The tubular body 4 in the above embodiment may have a single structure with a woven fabric, but as shown in FIG. 6A, it has a double or more multiple structure (triple structure in the illustrated example). In this case, the woven fabric 14 on the inner side tends to swell with the expansion of the cement fluid and the texture tends to expand, but the woven fabric 14 on the outer side is less susceptible to such influence. , The pressure is dispersed, the mesh size does not become large in all of the tubular body 4, and only the excess water can be more reliably removed from the mesh size of the tubular body 4. Further, even if there are protrusions on the slope N or the like, even if the outer woven fabric 14 is damaged by the protrusions, it is unlikely that the inner woven fabric 14 will be damaged, so that the tubular body 4 is formed. It will be hard to break as a whole. In addition, in FIG. 6A, a triple-layered woven fabric 14 and another triple-layered woven fabric 14 are stacked on the front and back sides, and the stacked ends are sewn together to form a tubular shape. An example of forming the body 4 is shown.

A linear core material (not shown) such as a PC steel wire or a net-like core material 15 (see FIG. 6B) is provided in the tubular body 4 in the above embodiment to improve the strength. You may try to plan. FIG. 6B shows an example in which a net-like core material 15 is sandwiched between the ends of the three-layered woven fabrics 14 when the ends of the woven fabrics 14 are sewn together in the same manner as in the example shown in FIG. ..

A reinforcing material such as steel fiber may be mixed with the cement fluid so that the effect of improving the strength of the tubular body 4 after curing can be obtained. Further, the effect of preventing cracks in the tubular body 4 after curing may be obtained by adding a curing retarding material to the cement fluid to reduce the curing speed.

In the above embodiment, the anchor pin is driven into the through hole 8 provided in the overhanging portion 7 of the tubular body 4, but instead of or in addition to this configuration, instead of the overhanging portion 7. Anchor pins may be driven into the main body of the tubular body 4. In this case, if surplus water is discharged to some extent after the cement fluid is contained and the anchor pin is directly driven into the main body of the tubular body 4 before the cement fluid is completely solidified, the anchor pin itself can be driven. It can be easily performed without receiving a large resistance from the cement fluid, and the tubular body 4 and the anchor pin are firmly integrated after the cement fluid in the tubular body 4 is solidified. Further, the inventors have confirmed that it is possible to prevent the leakage of the cement fluid from the tubular body 4 even if such an anchor pin is placed.

Needless to say, the modifications given in the present specification may be combined as appropriate.

1 Surface layer collapse prevention mat 2 Surface layer collapse prevention combined greening structure 3 Vegetation mat 4 Cylindrical body 5 Vertical flow path part 6 Horizontal flow path part 7 Overhanging part 8 Through hole 9 Connecting pipe 10 Pumping pump 11 Hose 12 Nozzle 13 Storage Part 14 Woven cloth 15 Net-like core material N Slope

Claims (4)

On one side of the vegetation mat, a tubular body composed of a woven cloth having a mesh that allows water to pass through and does not allow cement particles to pass through, and cement is placed in at least the flow path portion of the tubular body for circulating cement. A mat for preventing surface collapse, which is characterized by being installed in an unfilled state . Said tubular body, said channel portion, and a through-hole anchor pin can penetrate the through hole, the surface layer according to claim 1 which is provided at a position avoiding the channel portion Collapse prevention mat. A plurality of surface collapse prevention mats according to claim 1 or 2 are laid side by side on the ground, and the flow paths of the tubular bodies of the adjacent surface collapse prevention mats are connected to each other in a state of mutual communication. A greening structure that also prevents surface collapse and contains at least cement in its internal space. Table layer collapse prevention combined greening method you accommodate pouring at least cement in the flow path portion of the tubular body of shallow landslides antistatic mat according to laid claims 1 or 2 on the ground.

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