JP2007138624A - Reinforced earth construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reinforced earth construction method for constructing a reinforced earth structure stable over a long period of time by preventing the inclination and deformation of a wall surface material by looseness of geotextile when laid. <P>SOLUTION: Wall surface blocks 2 are stacked. Banking 3 is scattered every fixed layer thickness while performing rolling compaction of the banking 3 on the back face side of the wall surface blocks 2. Geotextile 4 is laid between the respective layers of the banking 3, and one end side 4a of the geotextile 4 is anchored in the wall surface block 2. The other end side 4b is pulled interposing an elastic body 6 so as not to be loose. At this time, the elongation amount of the elastic body 6 is confirmed by a strain gauge mounted on the elastic body 6, and pulling is performed while grasping tensile force introduced into the geotextile 4 from the elongation amount and a Young's modulus. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a reinforced earth method using a geotextile (woven fabric, nonwoven fabric, resin net, polymer grid, etc. using a synthetic polymer material) as an embankment reinforcement necessary for embankment stabilization, especially when laying the embankment reinforcement. It is intended to eliminate wall surface deformation caused by slack.

  Reinforced earth structures that are constructed as reinforced earth walls facing roads and residential land using embankments are generally laminated with multiple layers of wall materials such as panels and blocks, and construction residual soil and field excavated soil on the back side. It is constructed by embedding bank reinforcements such as geotextiles and steel strips in a plurality of layers for the purpose of filling the bank as a banking bank and stabilizing the banking and fixing the wall material.

  In particular, in the embankment structure constructed as a riverbank embankment, for example, as shown in FIGS. 5 (a) and 5 (b), a wall material is not used for embankment in order to green the slope. Direct slope slope is done.

  By the way, it is said that these reinforced earth structures are formed as structures due to friction between the embankment and the embankment reinforcing material laid in the embankment. In particular, the geotextile is deformable and can be easily pressed into the embankment. It is widely used because it has good workability for following, and has very high tensile strength.

JP 2002-242186 A JP 56-16730 A

  However, since geotextiles tend to sag when laid, the expansion of the geotextile is unavoidable until friction is generated between the geotextile and the pulling force, and the laminated wall material is displaced due to this elongation. There was a problem that the wall surface was deformed by tilting.

  In addition, when laying geotextiles, it is natural to pull the geotextile by hand so that no sagging occurs in the geotextile so far, but depending on the manual work, the geotextile should be evenly and sagging. It was impossible to pull with equal force.

  The present invention was made in order to solve the above problems, in particular, by eliminating slack when laying geotextile, by preventing the inclination of the wall material and the movement of the embankment caused by this slack, An object of the present invention is to provide a reinforced earth method capable of constructing a reinforced earth structure stable over a long period of time by effectively utilizing geotextiles.

  The reinforced earth construction method according to claim 1 is a method of laminating wall materials, rolling out the embankment on the back side of the wall material while rolling it at a constant layer thickness, laying geotextiles between each layer of the embankment, An elastic body that establishes a reinforcing structure by fixing one end side of the geotextile to the wall material, and is capable of grasping the occurrence of a predetermined tensile force that does not sag in the geotextile at the other end side of the geotextile And then rolling the embankment on the geotextile to a certain layer thickness and rolling it.

  In particular, the present invention provides a pulling force to the geotextile by laying the geotextile in the embankment by applying a light tension to the geotextile so that the sagging of the geotextile that has been unavoidable at the time of laying the geotextile will not occur. At the same time, a frictional force is generated between the embankment and the embankment so as to prevent deformation of the wall material caused by sagging of the geotextile.

  For example, rubber members, spring members, etc. can be used as the elastic body for pulling the other end of the geotextile. By attaching a strain gauge to these members, the elongation and Young's modulus of these members can be used. The tensile force introduced into the geotextile can be confirmed.

  Therefore, when laying the geotextile, it is possible to almost completely eliminate the sagging of the geotextile by pulling the other end side of the geotextile within the elastic range of the geotextile while checking the tensile force introduced to the geotextile by this elastic body. .

  In addition, although these elastic bodies may be embedded in the embankment with being attached, they may be removed and used repeatedly.

  Moreover, as a means for pulling the other end side of the geotextile, a turnbuckle, a jack, or the like can be used.

  The wall material can be used without being restricted by the material, shape, etc. For example, a concrete panel, a concrete block, a steel panel, or the like can be used. Especially in the case of concrete blocks, it is a self-supporting shape, and the size is generally about 20 to 150 cm in height, 30 to 100 cm in width, and about 20 to 60 cm in depth considering ease of handling such as transportation and workability. And the weight is preferably about 20 to 150 kg.

  By the way, the present applicant confirmed whether or not the deformation of the reinforced soil wall surface can be suppressed by the present invention by measuring the deformation amount of the reinforced soil wall surface using an experimental device that models an actual reinforced soil wall surface. .

  As the experimental apparatus, a soil tank having a width of 56 cm, a height of 50 cm, and a length of 100 cm as shown in FIGS. 7A and 7B was used. The reinforced soil walls are stacked up to 5 levels of 55 cm × 10 cm × 1.5 cm wall panels 21 to which the modeled geotextile 20 is attached, and standard sand 22 is used as embankment on the back side of each wall panel 21. The geotextile 20 was alternately laid, and the height up to the fifth level was 50 cm. Further, the wall panels 21 and 21 are not coupled to each other, and both ends of each wall panel 21 are supported by the cut beams 23 and 23.

The geotextile 20 has a thickness of 0.1 cm, a width × length of 10 cm × 55 cm or 5 cm × 40 cm, and uses a non-woven fabric having a small Young's modulus (550 kN / m ² ), as shown in FIG. 2 or 3 sheets were attached to the center of each wall panel 21. A dial gauge 24 was attached to each wall panel 21.

  When the preparation for measurement was completed in this way, the cut beams 23, 23 of each wall panel 21 were removed at a stroke, whereby each wall panel 21 was pushed by the sand 22 as shown in FIG. . The amount of deformation of each wall panel 21 after deformation was measured with a dial gauge 24.

  In order to confirm the effect of suppressing the deformation of the wall panel according to the present invention, the deformation amount is measured by pulling lightly the end side of the geotextile 20 with a rubber material (for example, rubber band) 25 as shown in FIG. This was done in two ways, one that was laid out in such a way that it did not occur, and one that was laid in a normal state where no such measures were taken. Here, a rubber band of about 5 cm was pulled to 15 cm. The tensile force was about 1.5N. The measurement results are shown in the graphs of FIGS. 11 (a) and 11 (b).

  As is apparent from the graph, in any case, the deformation of the geotextile 20 shows the maximum deformation amount in the substantially central wall panel, and the maximum deformation amount when the two geotextiles of the present invention are attached is 5 mm (graph (b )), The maximum deformation in the general case was 9 mm (graph (a)).

  Thereby, the maximum deformation amount of the reinforced soil wall surface according to the present invention was about ½ compared to the deformation amount of the reinforced soil wall surface by the normal construction method, and the technical effect of the present invention was confirmed.

  The reinforced earth construction method according to claim 2 is a reinforced earth construction method for constructing a reinforced structure by rolling out the embankment while rolling the embankment at a constant layer thickness, and laying geotextiles between each layer of the embankment. One end side or both end sides of the geotextile is pulled through an elastic body capable of grasping the generation of a tensile force that does not sag in the geotextile, and then the embankment is rolled out on the geotextile to a certain layer thickness and rolled. It is a feature.

  The present invention is particularly suitable for the construction of a reinforced earth structure (for example, see FIGS. 5 (a) and 5 (b)) which has no wall material such as a concrete block and has a slope with a gentle slope on the embankment surface layer. Reinforced soil structure constructed as a dike, etc., and the embankment slope can be greened without using wall materials.

  In this case, the elastic body may be attached to both ends of the geotextile, or one end of the geotextile may be fixed and attached to only the other end to pull the geotextile.

The reinforced earth method according to claim 3 is the reinforced earth method according to claim 1 or 2,
The elastic body is a rubber member or a spring member having a strain gauge.

  In particular, since the rubber member and the spring member can be provided as relatively inexpensive parts, the labor can be saved and the construction period can be shortened by embedding it in the embankment without collecting it.

  The reinforced earth method according to claim 4 is the reinforced earth method according to any one of claims 1 to 3, wherein the elastic body is removed. In particular, the present invention is intended to reduce costs by allowing an elastic body to be used repeatedly.

  In any one of the reinforced earth construction methods according to claims 1 to 4, the other end side of the geotextile may be fixed in the embankment or a natural ground. As a method of fixing the other end of the geotextile in the embankment, for example, there is a method of using a support plate or a support block, and as a method of fixing to the natural ground, a natural ground anchor protruding from the natural ground is used. There are methods such as direct bundling or bundling to wire nets, rebar grids, lattice rebars, and beams laid on natural ground.

  The present invention can construct a reinforced soil structure such as a retaining wall very efficiently, and can prevent the movement of embankment and the displacement of wall materials due to sagging when laying geotextiles. A very stable reinforced soil structure can be constructed.

  1 to 6 show an example of a reinforced earth structure. In the figure, a plurality of wall blocks 2 are laminated on a foundation 1 as wall materials, and the back side of the wall blocks 2 is filled with embankments 3, Within the embankment 3, geotextiles 4 are laid in multiple layers.

  The wall surface block 2 is formed in a rectangular parallelepiped shape that can stand by itself in a stable state from unreinforced concrete, reinforced concrete, fiber reinforced concrete, or the like.

  Further, in order to prevent lateral displacement and the like between the upper and lower wall surface blocks 2 in the stacked state, the upper and lower side surfaces of each wall surface block 2 are engaged with each other and interlocked (not shown). Is formed. Further, a fixing groove 2 a for fixing one end side 4 a of the geotextile 4 is formed at the upper end of each wall block 2.

  For the embankment 3, locally generated materials such as excavated soil are mainly used, and the material is squeezed for every fixed layer thickness and is carefully pressed for each layer.

  One end side 4 a of each geotextile 4 is wound around the fixing rod 5, and the fixing rod 5 is inserted into the fixing groove 2 a of the wall block 2 to be fixed to the upper end portion of the wall block 2.

  As another method for fixing one end side 4a of each geotextile 4 to the wall surface block 2, for example, as shown in FIG. 2 (b), a fixing ring protruding from the back surface of the wall surface block 2 is used. For example, a fixing rod 5 in which one end side 4a of the geotextile 4 is wound around 2b is inserted, or one end side 4a of the geotextile 4 is simply sandwiched between the upper and lower wall surface blocks 2 and 2 stacked.

  In any case, the plurality of wall blocks 2 are integrally fixed by continuously inserting the fixing rods 5 into the fixing grooves 2a or the ring 2b of the plurality of wall blocks 2 adjacent in the lateral direction. be able to.

  On the other hand, the other end side 4 b of each geotextile 4 is fixed to an anchor block 7 embedded in the embankment 3 with a plurality of elastic bodies 6 interposed therebetween.

  More specifically, the other end 4 b of the geotextile 4 is wound around a fixing bar 8 made of channel steel or the like, and a plurality of elastic bodies 6 are interposed between the fixing bar 8 and the anchor block 7. The other end side 4b of the geotextile 4 is pulled with a constant tension so that no sagging occurs in the geotextile 4.

  In this case, in particular, since the elastic body 6 is attached to the other end of the geotextile 4 via the fixing bar 8, the entire geotextile 4 can be pulled evenly and evenly with a uniform force. Will not occur. The elastic body 6 is a rubber member such as a rubber band or a spring member such as a coil spring.

  Next, the reinforced earth method according to the present invention will be described in order based on FIG. 3 and FIG.

  First, the concrete foundation 1 is laid, and the back of the concrete foundation 1 is embanked to the top level of the concrete foundation 1 and carefully rolled.

  In this case, the concrete foundation 1 can be constructed by cast-in-place concrete or a precast concrete block formed for the foundation. Moreover, as shown in the figure, the geotextile may be laid on the embankment embanked to the upper end level of the concrete foundation 1 to stabilize the ground.

  Next, the first wall surface block 2 </ b> A is laminated on the concrete foundation 1. When laminating the wall surface block 2A, the wall surface block 2A and the concavo-convex portion (not shown) formed on the concrete foundation 1 are engaged so that the wall surface block 2A is not displaced.

  Next, the first-layer embankment 3A is rolled up to the upper end level of the wall surface block 2A on the back side of the laminated wall surface block 2A and is carefully rolled.

  Next, the first-layer geotextile 4A is laid on the embankment 3A, one end side 4a thereof is fixed to the upper end portion of the wall surface block 2A, and the elastic body 6 is attached to the other end side 4b.

  Next, after the elastic body 6 is interposed and the other end 4b of the geotextile 4A is pulled with a predetermined force to remove the slack of the geotextile 4A, the other end 4b of the geotextile 4A is fixed to the first anchor block 7A. To do. Moreover, the embankment 3B is sprinkled on the geotextile 4A and is carefully pressed.

  In addition, when pulling the other end 4b of the geotextile 4A, the elongation amount of the elastic body 6 is confirmed by a strain gauge (not shown) attached to the elastic body 6, and introduced into the geotextile 4A from this elongation amount and Young's modulus. Pull the other end of the geotextile 4A while grasping the pulling force.

  By doing so, it is possible to prevent the geotextile 4A from being broken due to excessive tension, and to safely pull the other end 4b of the geotextile 4A until there is no slack.

  Further, the other end 4b of the geotextile 4A can be pulled by a turnbuckle or the like.

  Next, the second-stage wall block 2B is stacked on the wall block 2A, and the second-layer embankment 3B is rolled up to the upper end level of the wall block 2B on the back side of the wall block 2B and carefully pressed.

  Next, a second-layer geotextile 4B is laid on the wall block 2B, one end side 4a is fixed to the upper end of the wall block 2B, and the elastic body 6 is attached to the other end side 4b.

  Next, the other end side 4b of the geotextile 4B is pulled through the elastic body 6 to eliminate the slack of the geotextile 4B, and then the other end side 4b of the geotextile 4B is fixed to the second-stage anchor block 7B. In this state, the embankment is sprinkled on the geotextile 4B and carefully rolled.

  In the same manner, the entire reinforced earth structure can be constructed very efficiently by constructing the wall block 2 of each step, the embankment 3 and the geotextile 4 of each layer.

  FIGS. 5 (a) and 5 (b) show an example of a reinforced soil structure constructed as a riverbank embankment. In the figure, the embankment 3 is filled to a predetermined height, and slopes 3a with gentle slopes on both sides thereof. , 3a are formed. In addition, the geotextile 4 is laid in a plurality of layers in the embankment 3.

  For the embankment 3, locally generated materials such as excavated soil are mainly used, and the material is squeezed for every fixed layer thickness and is carefully pressed for each layer. Further, each geotextile 4 is pulled with a certain amount of force from one end or both ends so that there is no slack.

  As a method of pulling the geotextile 4 so as not to sag, for example, as shown in FIG. 5A, the both ends 4a, 4a of the geotextile 4 are pulled via the elastic body 6, and FIG. 2, there is a method in which one end side 4 a of the geotextile 4 is fixed and the other end side 4 b is pulled through the elastic body 6, any of which may be adopted.

  Next, the reinforced earth method according to the present invention will be described in order based on FIGS. 6 (a) to 6 (e).

  First, a first-layer geotextile 4A is laid on the ground, and both ends 4a and 4a of the geotextile 4A are pulled through the elastic body 6 to eliminate sagging of the geotextile 4, and then both ends 4a and 4a are placed on the ground. It is fixed by an anchor member. The first-layer geotextile 4A is particularly effective for embankment construction on soft ground, and is laid to prevent ground damage due to embankment load, to prevent dredging of sediment and mixing with soft soil. is there.

  Next, the first fill 3A is rolled up to a predetermined thickness on the geotextile 4A and then carefully pressed. Further, slopes 3a and 3a having gentle slopes are formed on both sides of the embankment 3A, respectively.

  Next, a second-layer geotextile 4B is laid on the embankment 3A, and both ends 4a and 4a of the geotextile 4B are pulled through the elastic body 6 to eliminate sagging of the geotextile 4B, and thereafter both ends 4a and 4a. To fix. Then, the second-layer embankment 3B is rolled up to a predetermined thickness on the geotextile 4B and carefully pressed. Further, slopes 3a and 3a having a gentle gradient are formed on both sides of the embankment 3B.

  In the same manner, the entire reinforced soil structure can be constructed very efficiently by alternately applying the embankment and geotextile of each layer.

  The present invention can construct a reinforced earth structure such as a retaining wall very efficiently, and can prevent the movement of embankments and the displacement of wall materials due to sagging when laying geotextiles.

It is a longitudinal cross-sectional view which shows an example of a reinforced earth structure. (A), (b) is a partial perspective view which shows the method of fixing the one end side of a geotextile to a wall surface block, (c) is a partial perspective view which shows the method of fixing the other end side of a geotextile to an anchor block. is there. (A)-(d) is sectional drawing which shows a construction procedure. (A), (b) is sectional drawing which shows a construction procedure. (A), (b) is a longitudinal cross-sectional view which shows an example of the reinforced earth structure constructed as a bank of a riverbed. (A)-(e) is sectional drawing which shows a construction procedure. The experimental apparatus which modeled the actual reinforced earth wall is shown, (a) is a longitudinal cross-sectional view, (b) is a cross-sectional view. It is a perspective view of the modeled wall surface panel. It is a perspective view of the deformed wall surface panel. It is a partial top view of the reinforced earth wall modeled. It is a graph which shows the measurement result of the deformation | transformation amount of a wall panel, (a) is the measurement result of the deformation amount of the reinforced earth wall surface constructed | assembled by the conventional general reinforcement earth method, (b) is the reinforcement earth method of this invention It is a graph which shows the measurement result of the deformation of the constructed reinforced earth wall surface, respectively.

Explanation of symbols

1 Foundation 2 Wall Block 3 Embankment 4 Geotextile 5 Fixing Bar 6 Elastic Body 7 Anchor Block 8 Fixing Bar

Claims (4)

  Laminate the wall material, roll out the embankment on the back side of the wall material while rolling it to a certain layer thickness, lay geotextile between each layer of the embankment, and fix one end side of the geotextile to the wall material A reinforcing earthwork method for constructing a reinforcing structure, wherein the other end of the geotextile is pulled through an elastic body capable of grasping the occurrence of a predetermined tensile force that does not sag in the geotextile, and then the geotextile A reinforced earth method characterized by rolling up the embankment to a certain thickness and rolling it.   It is a reinforced earth method that constructs a reinforcement structure by rolling out the embankment while rolling the embankment at a certain layer thickness, and laying geotextiles between the respective layers of the embankment, wherein one or both ends of the geotextile are connected to the geotextile. A reinforced earth method characterized in that after stretching through an elastic body capable of grasping the generation of a predetermined tensile force that does not cause sagging, the embankment is spread over the geotextile to a certain layer thickness and rolled.   The reinforced earth method according to claim 1 or 2, wherein the elastic body is a rubber member or a spring member provided with a dial gauge.   The reinforced earth method according to any one of claims 1 to 3, wherein the elastic body is removed after laying the geotextile.

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