JP2017206828A - Embankment reinforcement method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an improved embankment reinforcement method capable of improving the resistance performance against the tractive force while reinforcing an embankment wall compared to conventional block mats.SOLUTION: Disclosed is an embankment reinforcement method using a soil reinforcement block mat in which a reinforcement block is bonded and fixed to a block mat sheet. The reinforcement sheet is previously integrated with one end of the block mat sheet. The reinforcement sheet is embedded in an embankment body.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a bank or coastal dike reinforcement method.

Conventionally, embankment or slope protection work, for example, laying and solidifying the soil surface to be protected, laying a filter, stacking chestnuts, and then putting a concrete block while applying cement mortar to the joint I was stuck.
However, such a construction method has the disadvantages that it takes time and effort, and the construction period is prolonged, and a skilled worker is required for pasting concrete blocks.

Therefore, in order to eliminate these drawbacks, a mat for preventing surface erosion (block mat) in which a concrete block is bonded to a sheet of woven fabric or the like in advance is produced at the factory, and this mat is prepared after leveling the slope to be protected. A device for laying the door is disclosed (for example, Patent Document 1).
Ordinary slope protection works (block mats and revetment blocks) are placed on the slope, and are fixed with anchor pins (stakes) if necessary. The block laid on the slope resists the sweeping force of the water flow by the resistance force determined by its weight and shape.

JP 2011-026947 A

However, on coastal dikes and river dikes, there are cases where slope protection works are destroyed and washed away when a tsunami or river water flows over the dike. For example, as shown in FIG. 15, (1) the water flow destroys the coastal levee due to the action of the pushing wave, (2) the protection work on the back slope is lost due to the high speed of the water flow at the top edge, and (3 ) There is a risk that the levee breaks down due to the loss of the crest and the gap of the protective work.
The present invention has been devised in view of such conventional circumstances, and has improved the resistance to the scavenging force as compared with the conventional block mat and can also reinforce the embankment embankment. The purpose is to provide a dike reinforcement method.

As a result of intensive studies, the inventors have previously integrated a reinforcing sheet at the end portion of the block mat, and embedded the reinforcing sheet in the levee body, thereby increasing the sweeping force acting on the block. The present inventors have realized that the frictional force between the sheet and the embankment soil and the tensile force of the sheet can be taken into consideration.
That is, the present invention is as follows.
[1]
A dike reinforcement method using a block mat for ground reinforcement in which a block for reinforcement is bonded and fixed to a sheet for block mat.
(1) integrating the block mat sheet and the reinforcing sheet so that the reinforcing sheet extends to one end side of the block mat;
(2) Excavating the slope of the bank slope,
(3) The first block mat is laid on the excavated butt portion with the end of the reinforcing sheet aligned with the butt portion.
(4) Filling and rolling to a predetermined height so as to fill the reinforcing sheet of the first block mat,
(5) Excavating the upper part of the embankment of the bank slope.
(6) Laying the second block mat so as to cover the slope of the embankment with the reinforcing block portion;
(7) Laying the reinforcing sheet of the second block mat so as to cover the upper surface of the embankment;
(8) Embanking to a predetermined height so as to fill the reinforcing sheet of the second block mat,
(9) Excavating the upper part of the second block mat of the dike slope.
(10) Repeat (6) to (9),
An embankment reinforcement method characterized by comprising:
[2]
The embankment reinforcement construction method according to [1], wherein the length of the reinforcing sheet is 1 m or more.
[3]
The embankment reinforcement construction method according to [1] or [2], wherein the reinforcing sheet is one selected from the group consisting of woven fabric, non-woven fabric, geogrid and wire mesh, or a combination of two or more.
[4]
The bank reinforcement method according to any one of [1] to [3], wherein in the step (1), the block mat sheet and the reinforcing sheet are overlapped and joined.
[5]
In the step (1), the embankment reinforcing method according to any one of [1] to [3] 3, wherein the reinforcing sheet is joined to one end of the block mat sheet.
[6]
The embankment reinforcement construction method according to any one of [1] to [5], wherein the levee body slope to which the construction method is applied is the inside of the levee.

  In the present invention, a reinforcing sheet is integrated in advance at the end portion of the block mat, and the reinforcing sheet is embedded in the dam body, so that the scavenging force acting on the block can be combined with the sheet and the dam body soil. Provide an improved embankment reinforcement method that can take into account frictional force and sheet tensile force, improve resistance to scavenging force over conventional block mats, and can also reinforce embankment embankments be able to.

Sectional drawing which shows typically the embankment protection construction formed by the embankment reinforcement construction method of this invention. The figure which shows an example of the block mat used in this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the embankment reinforcement construction method of this invention. The schematic diagram for demonstrating the damage mechanism from a dike back slope protection work.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view schematically showing a bank protection work formed by the bank reinforcement method of the present invention.
The dike reinforcement method of the present invention is a dike reinforcement method using a ground reinforcing block mat 1 in which a reinforcing block 3 is bonded and fixed to a block mat sheet 2 and is reinforced at one end of the block mat sheet 2. The construction sheet 4 is integrated in advance, and the reinforcing sheet 4 is embedded in the levee body.
In embankment slope reinforcement work using a block mat, by embedding the reinforcing sheet 4 in the levee body, the frictional force between the sheet and the levee soil and the tensile force of the sheet are added to the tractive force acting on the block. It is possible to improve the resistance to the scavenging force as compared with the conventional block mat and to reinforce the embankment embankment.

First, the block mat 1 used in the construction method of the present invention will be described.
Fig.2 (a) is a top view which shows an example of the block mat 1 used in this invention.
The ground reinforcing block mat 1 is formed by adhering and fixing a plurality of reinforcing blocks 3 to a block mat sheet 2 made of a fabric that is impermeable to earth and sand particles having water permeability and flexibility. The reinforcing block 3 is arranged in alignment with the block mat sheet 2 and is integrally fixed by an adhesive body or a fixed body.

The block mat sheet 2 has good water permeability to the ground surface through the sheet, and possesses an anti-erosion function for preventing the ground surface sediment from flowing out by the sheet, and a sheet having a filter effect is used. . Here, the filter effect is an effect of preventing permeation of earth and sand while having water permeability. As the block mat sheet 2 having such an effect, a sheet having a mesh such as a woven fabric or a knitted fabric is preferable. Used. Although the degree of filter effect and water permeability can be controlled by the size of the mesh, those having a mesh of 1 mm ² or less are preferably used in the present invention.

  Further, it is desirable that the block mat sheet 2 is excellent in flexibility, is well adapted to the ground surface, has good adhesion, and can be used for soft ground where there is a risk of uneven settlement. Therefore, the material for the block mat sheet 2 includes synthetic fibers, polyethylene fibers, polypropylene fibers and other olefin fibers, polyamide fibers, polyester fibers, polyvinylidene chloride fibers, polyvinyl alcohol fibers and other general purpose fibers, carbon fibers, and aromatic fibers. Examples thereof include functional fibers such as polyamide, natural fibers, and regenerated chemical fibers. These may be used alone or in combination. A taslan yarn or a spun yarn may be used. The block mat sheet 2 may be a woven fabric or a knitted fabric as long as it has a mesh, but the block mat sheet 2 according to the present invention is preferably a woven fabric with less elongation.

  There are no particular restrictions on the distance in the longitudinal direction and width direction of the reinforcing block 3 that is adhesively fixed to the block mat sheet 2, but it is usually preferable that the distance is about 30 mm or less, and the reinforcing blocks 3 are arranged almost continuously.

For the adhesion and fixing of the reinforcing block 3 made of concrete to the block mat sheet 2, an inorganic or organic adhesive or an adhesive mixed with these is usually used. As the inorganic adhesive, for example, a hydraulic cement composition such as mortar or concrete can be used. Organic adhesives that use thermosetting resins such as epoxy resins, urethane resins, acrylic resins, silicone resins, epoxy acrylate resins, and phenol resins, thermoplastic resins such as polyamide resins, polyester resins, and ethylene vinyl alcohol resins And those using synthetic rubber such as styrene butadiene rubber, chloroprene rubber, butyl rubber, etc., and an epoxy resin excellent in strength and curability is preferably used.
Further, after the block mat sheet 2 is brought into contact with an uncured concrete block, the concrete block may be cured to adhere the concrete block to the block mat sheet 2.

The reinforcing sheet 4 is integrated so as to extend to one end side of the block mat sheet 2.
As shown in FIG. 2 (b), the reinforcing sheet 4 may be overlapped and joined to the lower side of the block mat sheet 2, and as shown in FIG. 2 (c), the reinforcing sheet 4 is Further, it may be joined to one end side of the block mat sheet 2.
The reinforcing sheet 4 is preferably one from the group consisting of woven fabric, non-woven fabric, geogrid and wire mesh, or a combination of two or more. As the woven fabric, the same one as the block mat sheet 2 described above can be used.
The reinforcing sheet 4 may be the same as the block mat sheet 2 described above. That is, in the block mat sheet 2, a blank portion where the block 3 is not bonded and fixed may be kept long, and the blank portion may constitute the reinforcing sheet 4. Alternatively, a reinforcing sheet 4 may be used as the block mat sheet 2 as shown in FIG.
The length of the reinforcing sheet 4 embedded in the bank body in the slope reinforcement work is preferably 1 m or more. By setting it to 1 m or more, it is possible to sufficiently secure the frictional force between the reinforcing sheet 4 and the levee body soil when embedded in the levee body.

As the reinforcing sheet 4, a geogrid is preferably used. By using the geogrid, the frictional force between the sheet and the embankment soil can be increased.
Geogrid is a grid-like polymer material, and is used as a surface reinforcing material or a layer thickness management material for embankment reinforcement laid on the embankment when constructing a reinforced earth wall. In order to satisfy the above, it is possible to use a material in which the strength, thickness, thickness of the polymer material, vertical and horizontal intervals, and the like are appropriately adjusted.
As a geogrid, for example, a single polymer material such as polyethylene, polypropylene, ethylene vinyl acetate copolymer (EVA), polyester, polyamide, or the like, or a coating material of these polymer materials, and further, an aramid A fiber, a high-stretched polypropylene fiber, a high-stretched polypropylene tape, a high-strength fiber such as a high-stretched polyacetal fiber, or a tape containing a tape or the like can also be used.

  However, if the reinforcing block 3 is to be bonded and fixed directly to the geogrid, it is difficult to secure a contact area between the mesh-like geogrid and the reinforcing block 3, and there is a possibility that it cannot be firmly fixed. Therefore, a combination of woven fabric and geogrid is used. It is preferable that the reinforcing block 3 is bonded and fixed to the upper surface of the woven fabric as the block mat sheet 2 and a geogrid is disposed and bonded to the lower side or one end as the reinforcing sheet 4. By using a combination of the woven fabric and the geogrid, it is possible to ensure the fixing of the reinforcing block 3 and a high frictional force between the sheet and the dam body soil. It is also conceivable that the reinforcing block 3 is arranged on the upper surface of the geogrid and a woven fabric is arranged on the lower side thereof. In this case, the adhesive is also supplied to the lower woven fabric through the mesh of the geogrid, and the reinforcing block 3 is bonded and fixed to both the geogrid and the woven fabric.

  In addition, the connection method between the geogrid and the block mat sheet 2 is not particularly limited, and it is possible to select and connect means such as thermal welding, adhesion, mechanical connection using a connection jig, and sewing. However, it is preferable to connect by heat welding or adhesion, and it is more preferable to connect by adhesion with a hot melt adhesive. By using a hot melt adhesive and connecting the geogrid and the block mat sheet 2 in the longitudinal direction while having an overlapping portion in the surface direction, it is possible to ensure a stable and high connection strength. .

Hot melt adhesives include polyolefin, polyurethane, ethylene-vinyl acetate copolymer, polyamide, polyester, thermoplastic elastomer, styrene-butadiene copolymer, styrene-isoprene copolymer, etc. These may be used alone or in combination.
In addition to hot melt adhesives, for example, polyvinyl acetate adhesives, polyacrylate ester adhesives, cyanoacrylate adhesives, ethylene copolymer adhesives, polyolefin adhesives, cellulose adhesives , Polyester adhesive, polyamide adhesive, polyimide adhesive, phenolic resin adhesive, epoxy adhesive, polyurethane adhesive, solvent type such as reactive (meth) acrylic adhesive, emulsion type An adhesive such as a solventless type can also be used.

  As described above, when the geogrid and the block mat sheet 2 are connected by welding or bonding such as hot melt, the shape is different, so that a high connection strength is obtained by a method of connecting sheets at a construction site or the like. It is difficult. In the present invention, by using a composite in which the geogrid and the block mat sheet 2 are connected in advance, the composite can be connected with a minimum of effort at the construction site, and high reliability can be ensured.

3-14 is a schematic diagram for demonstrating the embankment reinforcement construction method of this invention.
The dyke reinforcement method of the present invention is a dyke reinforcement method using the ground reinforcement block mat 1 in which the reinforcement block 3 is bonded and fixed to the block mat sheet 2 as described above, and includes the following steps:
(1) integrating the block mat sheet and the reinforcing sheet so that the reinforcing sheet extends to one end side of the block mat;
(2) Excavating the slope of the bank slope,
(3) The first block mat is laid on the excavated butt portion with the end of the reinforcing sheet aligned with the butt portion.
(4) Filling and rolling to a predetermined height so as to fill the reinforcing sheet of the first block mat,
(5) Excavating the upper part of the embankment of the bank slope.
(6) Laying the second block mat so as to cover the slope of the embankment with the reinforcing block portion;
(7) Laying the reinforcing sheet of the second block mat so as to cover the upper surface of the embankment;
(8) Embanking to a predetermined height so as to fill the reinforcing sheet of the second block mat,
(9) Excavating the upper part of the second block mat of the dike slope.
(10) Repeat (6) to (9),
It is characterized by having.
Hereinafter, each step will be described in detail.

(1) The block mat sheet and the reinforcing sheet are integrated so that the reinforcing sheet extends to one end side of the block mat.
As shown in FIG. 2, the block mat sheet and the reinforcing sheet may be overlapped and joined (FIG. 2 (b)), or the reinforcing sheet may be joined to one end of the block mat sheet. Good (FIG. 2 (c)).
When the block mat sheet 2 and the reinforcing sheet 4 are connected by welding or adhesion such as hot melt, it is difficult to obtain high connection strength by connecting the sheets at a construction site because the shapes are different. It is. In this step, it is preferable that the block mat sheet and the reinforcing sheet are integrated in advance at a factory or the like. In the present invention, by using a composite in which the geogrid and the block mat sheet 2 are connected in advance, the composite can be connected with a minimum of effort at the construction site, and high reliability can be ensured.
Note that this step can be omitted when the same sheet is used as the block mat sheet and the reinforcing sheet.

(2) Excavating the slope 11 of the bank slope 10.
As shown in FIGS. 3 and 4, the slope 11 of the levee slope 10 is excavated.

(3) The first block mat is laid on the excavated butt portion 11 with the end of the reinforcing sheet 4 aligned with the butt portion 11.
As shown in FIG. 5, the block mat 1 is laid with the end of the reinforcing sheet 4 aligned with the buttock 11. The block portion may be fixed by driving an anchor pin or the like.

(4) Fill and roll up to a predetermined height to fill the reinforcing sheet 4.
As shown in FIG. 6, the embankment 12 is applied on the reinforcing sheet 4. The embankment 12 is formed in a substantially trapezoidal shape having a slope 13 and an upper surface 14. A slope material that defines the slope 13 of the embankment 12 may be used.
Next, the upper surface 14 of the embankment 12 is pressed to form a flat rolling surface. Thereby, the reinforcing sheet 4 can be firmly embedded in the bank body.
In the subsequent step (6), when the portion of the reinforcing block 3 of the block mat 1 is laid on the slope 13 of the embankment 12, the method of the embankment 12 is performed so that the block portion does not become excessive or insufficient. The length of the surface 13 is preferably substantially the same as the length of the block portion of the block mat 1.
Further, when the reinforcing sheet 4 is laid on the upper surface 14 of the embankment 12 in the subsequent step (7), the reinforcing sheet 4 does not remain when laying the reinforcing sheet 4 of the block mat 1. Furthermore, the length of the upper surface 14 of the embankment 12 is preferably longer than the length of the reinforcing sheet 4.

(5) Excavate the upper part of the embankment 12 in the bank slope 10.
As shown in FIG. 7, the upper part of the embankment 12 in the bank slope 10 is excavated.

(6) Laying the second block mat 1 so as to cover the slope 13 formed by the embankment 12 with the portion of the reinforcing block 3,
As shown in FIG. 8, the portion of the reinforcing block 3 of the second block mat 1 is laid on the slope 13 of the embankment 12. At this time, the reinforcing sheet 4 of the block mat 1 is bent and overlapped on the reinforcing block 3 side.
The portion of the reinforcing block 3 may be fixed to the slope 13 by driving an anchor pin or the like. Thereby, the reinforcing block 3 can be firmly laid.

(7) The reinforcing sheet 4 of the second block mat 1 is laid so as to cover the upper surface 14 of the embankment 12.
As shown in FIG. 9, the reinforcing sheet 4 is rotated so as to cover the upper surface 14 of the embankment 12 by rotating the reinforcing sheet 4 around the joint portion of the reinforcing block 3 and the reinforcing sheet 4. Lay down.

(8) Embank to a predetermined height so as to fill the reinforcing sheet 4 of the second block mat 1.
As shown in FIG. 10, the embankment 12 is applied on the second reinforcing sheet 4, and the upper surface 14 of the embankment 12 is rolled to form a flat rolling surface.
As a result, the reinforcement of the slope bottom portion 11 of the slope 10 (first sheet) and the laying of the first stage block mat 1 (second sheet) on the slope 13 are completed.

(9) The upper part of the second block mat 1 is excavated from the bank slope 10.
(10) Repeat (6) to (9) until a predetermined height is reached.
The third and subsequent (second and subsequent) block mats 1 are similar to the laying of the second (first) block mat 1 described in (6) to (9). A series of steps consisting of laying, laying of the reinforcing sheet 4 (FIG. 12), embankment and rolling (FIG. 13), and excavation of the slope are advanced and repeated until a desired height is reached (FIG. 14).
In addition, materials other than embankment may be piled up on the top to form asphalt such as a management road, concrete pavement, or to construct other structures.

The levee protection work formed as described above is that the reinforcing sheet is embedded in the levee body, so that the frictional force between the sheet and the levee body soil and the tensile force of the sheet are added to the tractive force acting on the block. In addition, resistance to the scavenging force is improved as compared with the conventional block mat, and the embankment embankment is also reinforced.
In particular, since the purpose of the present invention is to prevent the destruction of the slope protection work and the loss when the tsunami and river water flow over the bank on the coast or river bank, the bank reinforcement method of the present invention. It is preferable that the slope of the levee body to be subjected to is the inside of the levee. Of course, the construction method of the present invention can also be applied to the reinforcement work on the outer slope of the bank and the slope reinforcement work other than the bank.

  Although the embodiment of the present invention has been described above, the present invention is not limited to this, and can be appropriately changed without departing from the spirit of the invention.

  By using the construction method according to the present invention, the resistance to the scavenging force can be improved and the embankment embankment can be reinforced, and can be widely used as a reinforcement method for the dike slope.

1: Block mat for ground reinforcement 2: Sheet for block mat 3: Reinforcing block 4: Reinforcing sheet 10: Slope 11: Slope 12: Fill 13: Slope 14: Top

Claims (6)

A dike reinforcement method using a block mat for ground reinforcement in which a block for reinforcement is bonded and fixed to a sheet for block mat.
(1) integrating the block mat sheet and the reinforcing sheet so that the reinforcing sheet extends to one end side of the block mat;
(2) Excavating the slope of the bank slope,
(3) The first block mat is laid on the excavated butt portion with the end of the reinforcing sheet aligned with the butt portion.
(4) Filling and rolling to a predetermined height so as to fill the reinforcing sheet of the first block mat,
(5) Excavating the upper part of the embankment of the bank slope.
(6) Laying the second block mat so as to cover the slope of the embankment with the reinforcing block portion;
(7) Laying the reinforcing sheet of the second block mat so as to cover the upper surface of the embankment;
(8) Embanking to a predetermined height so as to fill the reinforcing sheet of the second block mat,
(9) Excavating the upper part of the second block mat of the dike slope.
(10) Repeat (6) to (9),
An embankment reinforcement method characterized by comprising:   The embankment reinforcing method according to claim 1, wherein the length of the reinforcing sheet is 1 m or more.   The embankment reinforcement construction method according to claim 1 or 2, wherein the reinforcing sheet is one selected from the group consisting of woven fabric, non-woven fabric, geogrid and wire mesh, or a combination of two or more.   The embankment reinforcement construction method according to any one of claims 1 to 3, wherein in the step (1), the block mat sheet and the reinforcing sheet are overlapped and joined.   The embankment reinforcement construction method according to any one of claims 1 to 3, wherein, in the step (1), the reinforcing sheet is joined to one end of the block mat sheet.   The levee reinforcement construction method according to any one of claims 1 to 5, wherein the levee slope is subjected to the construction method.