Construction method of retaining wall structure

Abstract

To realize a retaining wall structure having a simple constitution, requiring little labor for construction, and having a large structural strength.SOLUTION: A retaining wall structure 5 is formed by stacking a plurality of embankment structures 16. The embankment structure 16 includes a front wall surface member 6 and a rear wall surface member 11 made of expanded metal. Filling soil 15 is filled between the front wall surface member 6 and the rear wall surface member 11 and tamped down. A bottom surface portion 8 of the front wall surface member 6 and a bottom surface portion 12 of the rear wall surface member 11 are connected by a coil 20 and a connecting rod 21 inserted into the coil 20. A rear surface portion 13 of the rear wall surface member 11 of the lower embankment structure 16 and the rear surface portion 13 of the rear wall surface member 11 of the upper surface embankment structure 16 are connected by the coil 20 and the connecting rod 21 inserted into the coil 20.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention can be applied to many places, such as mountainside retaining walls in mountainous areas, protective walls against falling rocks and collapsed soil, new construction and widening of roads, and river bank protection. Construction method of retaining wall structure Regarding. [Background technology]

[0002] Conventionally, a retaining wall structure is a structure and construction method in which embankment structures are constructed in multiple stages from below. In such a retaining wall structure, an L-shaped wall material is installed facing the wall surface of the reinforced soil retaining wall, a mesh material is laid and connected to the wall material, and the embankment is buried on the back side of the wall material and on top of the mesh material (see Patent Documents 1 and 2).

[0003] A configuration in which components constituting a rockfall protection fence (for example, a front wall material and a rear wall material, or a front wall material and a bottom material) are connected with a coil and a connecting rod is known (see Patent Document 3).

[0004] Also known is an embankment structure in which a base wall material with a roughly L-shaped cross section consisting of a side portion and a bottom portion and a flat upper wall material are partially overlapped, and a connecting device having an annular ring portion and a hook portion is used, and earth is piled up on the back side of each wall material in sequence, with embankment reinforcement material laid between the upper and lower embankments (see Patent Document 4). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2004-250913 A [Patent Document 2] JP 2010-112133 A [Patent Document 3] Patent No. 6471042 [Patent Document 4] Patent No. 4986967 Summary of the Invention [Problem to be solved by the invention]

[0006] As described in Patent Documents 1 and 2, resin geogrids are used for the mesh, which require cutting and tensioning on-site, and have problems such as difficulty in maintaining the shape of the backside laying and connecting, making construction cumbersome and costly. Patent Document 3 is merely a configuration for forming a rockfall protection fence, and is not necessarily suitable for the configuration of a retaining wall structure formed by stacking multiple embankment structures.

[0007] Furthermore, as described in Patent Document 4, in a structure in which a roughly L-shaped base wall material and a flat upper wall material are partially overlapped and connected by a connector having an annular ring portion and a hook portion, a connector with a special configuration having an annular ring portion and a hook portion is required.

[0008] Furthermore, since part of the flat upper wall material is not buried in the embankment, and in order to withstand the earth pressure of the embankment, it is necessary to connect it to the reinforcing material with a stay belt, which makes the structure complex and increases the amount of work required for construction.

[0009] The present invention aims to solve the above-mentioned problems in the conventional art, and aims to realize a retaining wall structure that does not require the preparation of special wall materials that are separately produced and transported to a factory, has a simple structure, requires little construction work, has great structural strength, and has a wide range of applications such as protective walls in mountainous areas and river banks. [Means for solving the problem]

[0010] In order to solve the above-mentioned problems, the present invention provides a retaining wall structure formed by stacking embankment structures in a plurality of stages, each stage of the embankment structure having a front wall material and a rear wall material made of expanded metal, and fill soil is filled between the front wall material and the rear wall material and tamped down, the front wall material has a bottom surface and a front surface bent from the front end of the bottom surface at an angle upward and toward the rear surface, and is formed into a substantially angle-shaped shape in side view, a waling material is attached horizontally to the front surface so as to extend in the width direction, and a plurality of diagonal tie materials are attached between the front surface and the bottom surface at intervals in the width direction, and the upper ends of the diagonal tie materials are hung on the waling material, and the rear wall material the upper tier embankment structure is placed over the coil attached to the rear portion of the lower tier, and a retaining wall structure characterized in that the retaining wall structure has a bottom portion and a rear portion bent upward from the rear end of the bottom portion, a coil extending in the width direction is attached to the upper end of the rear portion, the bottom portion of the front wall material and the bottom portion of the rear wall material are connected, the rear portion of the rear wall material of the lower tier embankment structure and the rear portion of the rear wall material of the upper tier embankment structure are connected by inserting a connecting rod therethrough with the coil attached to the rear portion of the lower tier, and the fill soil of the lower tier embankment structure is restrained by the front wall material and rear wall material of the embankment structure and the front wall material and rear wall material of the upper tier embankment structure.

[0011] The bottom surface of the front wall material and the bottom surface of the rear wall material are directly connected to each other by a coil and a connecting rod inserted into the coil, and it is preferable that the inclination angle of the rear surface portion relative to the bottom surface of the front wall material and the inclination angle of the rear surface portion relative to the bottom surface of the rear wall material are approximately the same.

[0012] It is preferable that backfill soil is filled between the rear wall material and the cut surface of the natural ground and tamped down.

[0013] The rear portion extends upward at an angle of approximately 90° relative to the bottom portion of the rear wall material, the flared material is attached horizontally to the rear portion of the rear wall material so as to extend in the width direction, and a plurality of diagonal tie materials are attached and suspended between the rear portion and the bottom portion at intervals in the width direction, and the bottom portion of the front wall material and the bottom portion of the rear wall material are connected via a horizontal reinforcement material formed from expanded metal, and it is preferable that the bottom portion of the front wall material and the bottom portion of the rear wall material are each connected by the horizontal reinforcement material, a coil, and a connecting rod inserted into the coil.

[0014] In order to solve the above-mentioned problems, the present invention provides a retaining wall structure comprising a lower group of multiple-stage embankment structures and an upper group of multiple-stage embankment structures formed on the lower group of multiple-stage embankment structures, wherein the embankment structure of each stage of the lower group of multiple-stage embankment structures comprises a front wall material and a rear wall material formed from expanded metal, and fill soil is filled and compacted between the front wall material and the rear wall material, and the front wall material has a bottom portion and a folded portion inclined upward and toward the rear side from the front end of the bottom portion. The rear wall material has a bottom portion and a rear portion bent upward from a rear end of the bottom portion, and a coil extending in the width direction is attached to the upper end of the rear portion. The rear wall material has a bottom portion and a rear portion bent upward from a rear end of the bottom portion, and a coil extending in the width direction is attached to the upper end of the rear portion. The bottom surfaces of the face materials are connected by a coil and a connecting rod inserted into the coil, and the back surface of the rear wall material of the lower level embankment structure and the back surface of the upper level embankment structure are connected by inserting a connecting rod into the coil with the back surface of the upper level embankment structure covered by the coil attached to the back surface of the lower level, and the fill soil of the lower level embankment structure is connected to the front wall material and rear wall material of the embankment structure and the bottom surface of the front wall material and rear wall material of the upper level embankment structure. and a surface portion, each stage of the embankment structure of the upper group includes a front wall material having a front portion and a bottom portion, and a horizontal reinforcement material formed from expanded metal, the bottom portion of the front wall material and the expanded metal horizontal reinforcement material are connected to each other by a coil and a connecting rod inserted into the coil, and the space between the multiple stages of the embankment structure of the upper group and the ground is filled with fill soil and compacted.

[0015] In order to solve the above problems, the present invention provides a method for constructing a retaining wall structure by stacking embankment structures in a plurality of stages, the embankment structures including a front wall material made of expanded metal and consisting of a bottom portion and a front portion extending upward from the front end of the bottom portion, and a rear wall material made of expanded metal and consisting of a bottom portion and a rear portion extending upward from the rear end of the bottom portion, the method comprising the steps of: for the first stage of the embankment structure, a coil is applied from below to the bottom portion of the front wall material, the bottom portion of the rear wall material is placed on top of the coil, a connecting rod is passed through the coil to connect the front wall material and the rear wall material, the coil is screwed into the upper portion of the rear portion of the rear wall material, and a suction prevention material and a waling material extending horizontally in the width direction are attached to the front portion of the front wall material, The present invention provides a method for constructing a retaining wall structure by stacking upper-level embankment structures in a manner that involves installing a diagonal tie material between the front and bottom parts of a front wall material, filling and tamping backfill soil between the rear wall material and the cut surface of the natural ground, and filling and tamping the space between the front wall material and the rear wall material, and constructing the second and subsequent embankment structures using the same process as the first embankment structure, and stacking the upper-level embankment structures in sequence, the method being characterized in that, when constructing the upper-level embankment structure on the lower-level embankment structure, the back part of the upper-level rear wall material is covered with a coil attached to the back part of the lower-level rear wall material and a connecting rod is inserted into the coil to connect the upper-level rear wall material to the lower-level rear wall material.

[0016] In order to solve the above-mentioned problems, the present invention provides a method for constructing a lower group of multiple stages of embankment structures by stacking multiple embankment structures each having a front wall material made of expanded metal and consisting of a bottom portion and a front portion extending upward from the front end of the bottom portion, and a back wall material made of expanded metal and consisting of a bottom portion and a back portion extending upward from the rear end of the bottom portion, and stacking multiple embankment structures on top of the front wall material made of expanded metal and consisting of a bottom portion and a front portion extending upward from the front end of the bottom portion, and horizontal reinforcement materials made of expanded metal. A construction method for a retaining structure constructed by stacking and constructing a plurality of embankment structures of an upper group, wherein for the first embankment structure of the plurality of embankment structures of the lower group, a coil is applied from below to the bottom surface of the front wall material, the bottom surface of the rear wall material is placed on top of that, and a connecting rod is inserted into the coil to connect them, the coil is screwed into the upper part of the rear part of the rear wall material, a suction prevention material and a waling material extending horizontally in the width direction are attached to the front part of the front wall material, a diagonal tie material is hung between the front part and the bottom part of the front wall material, and a connection is made between the rear wall material and the cut surface of the natural ground. Backfill soil is filled between the front wall material and the rear wall material and compacted, and the space between the front wall material and the rear wall material is filled with middle fill soil and compacted. For the second and higher tier embankment structures, the construction is carried out in the same process as for the first tier embankment structure, and the upper tier embankment structures are stacked in order. At this time, the coil attached to the rear part of the rear wall material of the lower tier embankment structure is covered with the rear part of the rear wall material of the upper tier embankment structure, a connecting rod is inserted into the coil, and the rear wall material of the upper tier is connected to the rear wall material of the lower tier. For the first tier embankment structure of the upper group of multiple tiers, a front wall material and horizontal reinforcement material are placed on the top surface of the uppermost embankment structure of the multiple-stage embankment structure in the side group, and connected with a coil and a connecting rod inserted into the coil; a suction prevention material and a waling material extending horizontally in the width direction are attached to the front part of the front wall material; a diagonal tie material is installed between the front part and the bottom part of the front wall material; the space between the front wall material and the natural ground is filled with fill soil and compacted; and the second and subsequent embankment structures of the multiple-stage embankment structure in the upper group are constructed in the same manner as the first embankment structure of the multiple-stage embankment structure in the upper group;The present invention provides a method for constructing a retaining wall structure, which is characterized by stacking upper layers of embankment structures in sequence. Effect of the Invention

[0017] According to the retaining wall structure and its construction method of the present invention, the front wall material and the rear wall material are connected by coils and connecting rods, and the rear wall materials of the upper and lower stage embankment structures are connected to each other and integrated by coils and connecting rods, and a configuration is adopted in which fill soil is filled into the space surrounded by the front wall material and rear wall material of the lower stage and the front wall material and rear wall material of the upper stage, which are connected to each other and integrated in this way.Since the fill soil is restrained and reinforced from the outside on its front, rear, bottom and top, a sturdy retaining wall structure with great load-bearing capacity and high earthquake resistance can be constructed. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a side view showing the overall configuration of a first embodiment of a retaining wall structure according to the present invention. [Diagram 2] FIG. 2 is a perspective view showing the state of forming an embankment structure constituting the retaining wall structure of Example 1. [Diagram 3] This is a side view showing the front wall material and the rear wall material, which are part of the embankment structure that constitutes the retaining wall structure of Example 1, (a) shows each of them, (b) shows the connected state to each other, and (c) shows the connection structure. [Figure 4] 1A and 1B are diagrams explaining the main parts and construction of the retaining wall structure of Example 1, where (a) shows the installation of diagonal tie members, (b) shows the filling of backfill soil, and (c) shows the formation of an upper-level embankment structure on top of a lower-level embankment structure. [Diagram 5] FIG. 2 is a perspective view showing the state in which the retaining wall structure of Example 1 is applied to a mountainous area. [Figure 6] FIG. 11 is a side view showing the overall configuration of a retaining wall structure according to a second embodiment of the present invention. [Figure 7] This is an oblique view showing the state in which an upper level embankment structure is formed on top of a lower level embankment structure in the retaining wall structure of Example 2. [Figure 8] FIG. 11 is a side view explaining the construction of the retaining wall structure of Example 2, where (a) shows the front wall material, the rear wall material and the horizontal reinforcement material, (b) shows the configuration in which the front wall material and the rear wall material are connected via the horizontal reinforcement material, and (c) shows the state in which an upper stage embankment structure is formed on top of a lower stage embankment structure. [Figure 9] FIG. 11 is a perspective view showing the state in which the retaining wall structure of Example 2 is applied to a mountainous area. [Figure 10] 11A and 11B are diagrams illustrating the overall configuration of a retaining wall structure according to a third embodiment of the present invention, where (a) shows the mountainside of the natural ground to which the structure is applied and its cut surface, and (b) is a side view showing the overall configuration of the third embodiment. [Figure 11] FIG. 11 is a side view illustrating the characteristic points of the configuration and construction of the retaining wall structure of Example 3 of the present invention, where (a) shows the multi-stage embankment structure of the lower group, and (b) is a diagram explaining the state of forming the lowest stage of the multi-stage embankment structure of the upper group, and an enlarged view showing the connection state of the front wall material and horizontal material, which are the key parts. [Figure 12] FIG. 11 is a perspective view showing the retaining wall structure of Example 3 applied to a mountainous area. BEST MODE FOR CARRYING OUT THEINVENTION

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A retaining wall structure and a construction method thereof according to the present invention will be described below with reference to the drawings based on an embodiment. EXAMPLES

[0020] Example 1 A first embodiment of a retaining wall structure and a construction method thereof according to the present invention will be described with reference to Figs. 1 to 5.

[0021] In the invention described in this specification and in the claims, when the retaining wall structure is viewed from the front facing the mountain side, the left and right directions are the width direction, the direction toward you is the front, the front side is the front side or front side, the depth direction opposite the front is the rear, and the depth side is the rear side or rear side (the mountain side if there is a bedrock on the rear side), and the view from the side of the front is the side view.

[0022] Incidentally, the retaining wall structure of the present invention is formed by stacking multiple tiers of embankment structures, but in the invention described in this specification and in the claims, the lower embankment structure and the upper embankment structure are referred to as the lower tier embankment structure and the upper tier embankment structure, respectively.

[0023] In Figure 1, a mountainside surface 1 of the natural ground (shown by an imaginary line in Figure 1) is excavated as shown by excavation line 2, and an inclined cut surface 3 is formed. In Example 1, a retaining wall structure 5 is constructed along the front side of the cut surface 3 formed at an incline on a mountainside or the like, and a construction method thereof will be described.

[0024] The retaining wall structure 5 of Example 1 is constructed by stacking multiple layers of embankment structures 16, each formed by filling the space between a front wall material 6 and a rear wall material 11 with fill soil 15, as shown in Figures 1, 2, and 5.

[0025] The retaining wall structure 5 of Example 1, which will be described in detail later, has a front portion 7 of the front wall material 6 and a rear portion 13 of the rear wall material 11 that incline toward the rear side at the same gradient, and are formed so as to lean against the cut earth surface 3 via backfill soil 17 (soil as backfill material) filled between them and the cut earth surface 3 on the rear side, and is also referred to as a leaning type retaining wall structure 5.

[0026] In the embankment structure 16 of each stage, as shown in Figures 1, 3(a) and (b), the front wall material 6 is formed by bending the expanded metal into a substantially angle shape to have a front portion 7 and a bottom portion 8. The front portion 7 is formed by bending from the front end of the bottom portion 8 toward the back side at an acute angle α with respect to the bottom portion 8.

[0027] 1, 3(a) and 3(b), the rear wall material 11 is made of expanded metal and has a bottom portion 12 and a rear portion 13 that is bent diagonally upward from the rear end of the bottom portion 12 to the rear side, and is formed in a substantially inverted L-shape. Here, the "substantially inverted L-shape" refers to a shape that is created when the free end of the long side of the L-shape is rotated, for example, to the right until the long side becomes horizontal.

[0028] More precisely, the rear wall material 11 has a rear portion 13, the rear of which is bent at an obtuse angle β with respect to the bottom portion 12 toward the rear side. Here, 180°-β=α. The front wall material 6 and the rear wall material 11 are formed to be inclined at the same acute angle α toward the mountain side with respect to the horizontal plane along which the bottom portions 8 and 12 respectively extend.

[0029] In summary, the front wall material 6 and the rear wall material 11 are formed with an inclination so as to have the same gradient toward the mountain side. Also, as shown in Fig. 3(a), the rear portion 13 of the rear wall material 11 is formed to be slightly longer toward the top than the front portion 7 of the front wall material 6.

[0030] The front wall material 6 and the rear wall material 11 are arranged on the bottom surface 4 of the cut earth surface 3 (the upper surface of the backfill soil 15 for the upper stage) with parts of their bottom parts 8, 12 overlapping each other as shown in Fig. 3(b), and the overlapping parts are connected by a coil 20 and a connecting rod 21. The connecting rod 21 is made of a steel bar.

[0031] 3(b) and (c), the connection structure 22 is constructed as follows: The coil 20 is applied from below to the bottom surface 8 of the front wall material 6 with its longitudinal direction facing the width direction. The bottom surface 12 of the rear wall material 11 is then placed over this, and a connecting rod 21 is inserted into the coil 20 in the width direction to form the connection structure 22 between the front wall material 6 and the rear wall material 11.

[0032] In the front part 7, the wale raising material 25 is attached by passing it through the upper end hook 27 of the diagonal tie material 26 so as to abut against the front side of the upper part and extend in the width direction of the front part 7. The wale raising material 25 is made of a metal bar such as a steel bar.

[0033] As shown in Figs. 1 to 4, a plurality of diagonal tie members 26 are attached to the front wall material 6 at intervals (see Fig. 2) in the width direction, spanning between the front portion 7 and the bottom portion 8. The diagonal tie members 26 reinforce the front wall material 6 against the earth pressure of the fill soil 15, and are made of metal bars such as steel.

[0034] As shown in Figures 2 and 3(b), the diagonal tie material 26 is attached to an upper end hook 27 protruding from the front surface portion 7 through a wale raising material 25, and its lower end hook 28 is attached by being hung on a connecting rod 21 inserted through a coil 20 attached to the bottom surface portion 8. The lower end hook 28 may be configured to be hung on a mesh of the bottom surface portion 8.

[0035] 1, 3(b), 4(a) and (b), a coil 20 is attached by screwing it in the width direction to the upper part of the back part 13 of the back wall material 11 (near the upper end above the upper end of the front part 7 of the front wall material 6). Furthermore, as shown in FIG. 4, a suction prevention material 31 (vegetation mat) is attached to the back side of the front wall material 6.

[0036] As shown in Figure 4(b), backfill soil 17 is poured into the gap between the rear wall material 11 and the cut earth surface 3 up to a height near the upper end of the front wall material 6 (a height slightly below the coil 20 attached to the rear portion 13) and compacted.

[0037] Furthermore, fill soil 15 is poured into the space between the front wall material 6 and the rear wall material 11 and compacted by a small roller. Fill soil 15 is made from soil generated on-site when cutting the natural ground to form the cut surface, etc., and crushed stone is added to make the soil permeable. This makes it possible to make effective use of the soil generated on-site and ensures permeability.

[0038] In the manner described above, one stage (e.g., the first stage) of the embankment structure 16 is formed, as shown in Fig. 4(b). On top of the embankment structure 16 thus formed (herein referred to as the lower stage embankment structure 16), a higher stage (e.g., the second stage) of the embankment structure 16 is formed as follows.

[0039] The formation of the upper-stage embankment structure 16 is almost the same as that of the lower-stage embankment structure 16. That is, when forming the upper-stage embankment structure 16, the front wall material 6 and the rear wall material 11 are placed on the top surface of the fill soil 15 of the lower-stage embankment structure 16, as shown in Figure 4(c). Then, as with the lower-stage embankment structure 16 described above, the front wall material 6 and the rear wall material 11 are connected by a coil 20 and a connecting rod 21.

[0040] In addition, when the front wall material 6 and the rear wall material 11 are arranged, the lower part of the front portion 7 of the front wall material 6 is abutted from the rear side against the upper end part 7 of the front portion 7 of the front wall material 6 of the lower stage embankment structure 16.

[0041] In addition, with regard to the rear wall material 11, the lower part of the rear portion 13 of the upper stage rear wall material 11 is covered from the front side with the coil 20 which has been previously attached to the upper part of the rear portion 13 of the rear wall material 11 of the lower stage embankment structure 16.

[0042] Furthermore, the connecting rod 21 is inserted into the coil 20 to connect the lower part of the rear part 13 of the rear wall material 11 to the upper part of the rear part 13 of the rear wall material 11 of the lower stage embankment structure 16 by the coil 20 and the connecting rod 21. The connection structure is the same as the configuration shown in Figure 3(c).

[0043] Thereafter, in the same manner as in the case of the lower stage embankment structure 16, the suction prevention material 31, the diagonal tie material 26 and the flank support material 25 are attached to the front wall material 6 as shown in FIG. 4(c).

[0044] Then, as in the case of the lower-stage embankment structure 16, backfill soil 17 is poured into the gap between the rear wall material 11 and the cut surface 3 of the natural ground and compacted, and further, middle fill soil 15 is poured into the space between the upper-stage front wall material 6 and the rear wall material 11 and compacted with a small roller to form the upper-stage embankment structure 16.

[0045] In this manner, upper embankment structures 16 are stacked one after another on top of the lowest embankment structure 16, forming a retaining wall structure 5 of a predetermined height, as shown in FIG. 1.

[0046] In the retaining wall structure 5 of Example 1, as shown in FIG. 4, the following configurations (1) to (3) were adopted. (1) The rear wall materials 11 of the upper and lower stages of the embankment structure 16 are connected to each other by coils 20 and connecting rods 21 to form an integrated structure. (2) A configuration in which fill soil 15 is filled in the space surrounded by the lower stage front wall material 6, the lower stage rear wall material 11, the upper stage front wall material 6, and the upper stage rear wall material 11. (3) The front wall material 6 is reinforced with diagonal tie material 26.

[0047] These configurations (1) and (2) function synergistically, and the fill soil 15 is externally confined and strengthened at its front, back, bottom and top by the upper-level front wall material 6 and back wall material 11, thereby constructing a sturdy retaining wall structure 5 that has great load-bearing capacity and is also resistant to earthquakes. However, since the topmost level embankment structure 16 does not have an upper level embankment structure, the fill soil 15 is not confined by the upper-level front wall material and back wall material.

[0048] In addition, the front wall material 6 and the rear wall material 11, which are made of expanded metal, are configured so that the bottom portions 8, 12, respectively, are directly connected to each other without any gap between them and without the use of a laying sheet or the like, thereby strengthening the constraint of the fill soil 15 as described above, simplifying the configuration, and reducing construction and costs.

[0049] In particular, the connections between the front wall material 6 and the rear wall material 11 in each stage of the embankment structure 16, and between the rear wall material 11 of the lower stage and the rear wall material 11 of the upper stage, are made using coils 20 and connecting rods 21, eliminating the need for bolt joints, etc., which were previously used.

[0050] Therefore, construction for such connections can be carried out simply, quickly and safely without the need for skilled craftsmen, making the retaining wall structure 5 and its construction method not only economical but also ideal for disaster recovery work and the like which requires speed.

[0051] Example 2 A retaining wall structure according to a second embodiment of the present invention will be described below with reference to Figures 6 to 9. A retaining wall structure 40 according to the second embodiment has a structure that is basically the same as that of the retaining wall structure 5 according to the first embodiment, and like the retaining wall structure 5 according to the first embodiment, a plurality of embankment structures 42 are formed by filling the space between a front wall material 6 and a rear wall material 41 with fill soil 15, as shown in the overall configuration in Figures 6 and 9.

[0052] However, the retaining wall structure 5 of Example 1 is a leaning type retaining wall structure that is installed on the front side of the cut surface 3 of the mountainside, as shown in Figure 1, and is formed so as to lean against the cut surface 3 of the mountainside via backfill soil 17, whereas the retaining wall structure 40 of Example 2 is not necessarily designed to be installed on the front side of the natural ground, and while there are cases in which it is applied to the front side of the natural ground, there are also configurations in which it is not installed on the front side of the natural ground.

[0053] In other words, the retaining wall structure 40 of Example 2 is not a leaning type retaining wall structure like that of Example 1, and is not necessarily formed so as to lean on the rear side via backfill soil. Regardless of whether there is natural ground on the rear side, the retaining wall structure 40 is a free-standing retaining wall structure that stands on its own, and is applicable not only to mountainous areas such as for retaining soil on mountainsides and for protection against falling rocks and collapsing soil, but also to location environments where there is no mountainside on the rear side, such as river banks, etc.

[0054] In the embankment structure 42 of each stage of the retaining wall structure 40 of the second embodiment, the front wall material 6 and the rear wall material 41 are each made of expanded metal, as shown in Figures 6 and 7. The front wall material 6 has the same structure as the front wall material 6 of the first embodiment.

[0055] 8(a), the rear wall material 41 has a rear portion 45 and a bottom portion 46, and the rear portion 45 is formed by bending the rear end of the bottom portion 46 toward the rear side at a substantially right angle to the bottom portion 46, so that the rear portion 45 has an L-shape in side view. The front portion 7 of the front wall material 6 and the rear portion 45 of the rear wall material 41 are formed to have substantially the same height.

[0056] The front wall material 6 and the rear wall material 41 are arranged with their respective bottom portions 8 and 46 spaced apart in the front-to-back direction on the upper surface 49 of the lower-level embankment structure 42 (the upper surface of the backfill soil 15; in the case of the lowest-level embankment structure, the horizontal bottom surface 50 of the ground or cut surface) as shown in Figure 8(b), and are connected to each other by coils 20 and connecting rods 21 via horizontal reinforcement members 53 made of expanded metal.

[0057] This connection is made as follows: Coil 20 is attached from below to the end on the rear side (mountain side) of bottom portion 8 of front wall material 6, and coil 20 is attached from below to the end on the front side of bottom portion 46 of rear wall material 41, and the front and rear ends of horizontal reinforcement member 53 are placed over the portions of bottom portion 8 and bottom portion 46 to which coil 20 is attached, and connecting rods 21 are inserted into each coil 20 to connect them.

[0058] 8(b), the coil 20 is attached by screwing it in the width direction to the upper end of the back part 45 of the back wall material 41. The front wall material 6 is attached with a suction prevention material 31 (vegetation mat), a diagonal tie material 26, and a wale raising material 25, similar to the front wall material 6 of the first embodiment.

[0059] As shown in FIG. 8(b), like the front wall material 6, the back wall material 41 is also provided with a suction prevention material 31 (vegetation mat), an inclined tie material 26 and a flaring material 25.

[0060] In the case of the rear wall material 41, the suction prevention material 31 (vegetation mat) is attached to the front side of the rear portion 45, and the wale-raising material 25 is attached to the rear side. Then, as shown in Figures 7 and 8(b), the diagonal tie material 26 is attached by passing the wale-raising material 25 through its upper end hook 27, and its lower end hook 28 is hung on the mesh of the bottom portion 46 and attached.

[0061] Then, as in the first embodiment, fill soil 15 is poured into the space between the front wall material 6 and the rear wall material 41 and compacted by a small roller. As fill soil 15, soil generated on-site, such as soil generated when cutting the natural ground, and crushed stone are added to impart permeability.

[0062] In this manner, one stage of the embankment structure 42 is formed in the retaining wall structure 40 of Example 2. On top of the embankment structure 42 thus formed, a higher stage of the embankment structure 42 is formed.

[0063] The formation of the upper-stage embankment structure 42 is substantially the same as that of the lower-stage embankment structure 42. That is, when forming the upper-stage embankment structure 42, the front wall material 6 and the rear wall material 41 are placed on the upper surface 49 of the fill soil 15 of the lower-stage embankment structure 42, as shown in Figure 8(b).

[0064] Then, similarly to the lower stage embankment structure 42 described above, the front wall material 6 and the rear wall material 41 are connected to each other by the coil 20 and the connecting rod 21 via the horizontal reinforcement material 53 .

[0065] When positioning the front wall material 6 and the rear wall material 41, as in the case of Example 1, the lower part of the front portion 7 of the front wall material 6 is abutted from the rear side against the upper end part 7 of the front portion 7 of the front wall material 6 of the lower-stage embankment structure 42, as shown in Figure 8(c).

[0066] For the rear wall material 41, the lower part of the rear portion 45 of the upper tier rear wall material 41 is placed from the front side over the coil 20 that has been previously attached to the upper part of the rear portion 45 of the lower tier rear wall material 41, as shown in Figure 8 (c), and the connecting rod 21 is inserted into the coil 20 to connect the lower part of the upper tier rear portion 45 to the upper part of the lower tier rear portion 45.

[0067] Then, in the same manner as in the case of the lower level embankment structure 42, suction prevention materials 31, diagonal tie materials 26 and flank members 25 are attached to the front wall material 6 and rear wall material 41, respectively, as shown in Figure 8 (c).

[0068] Furthermore, as in the case of the lower-stage embankment structure 42, fill soil 15 is poured into the space between the front wall material 6 and the rear wall material 41 and compacted by a small roller to form the upper-stage embankment structure 42.

[0069] In this way, higher embankment structures 42 are stacked one after another on top of the lowest embankment structure 42, forming the retaining wall structure 40 of Example 2 of a predetermined height, as shown in Figures 6 and 9.

[0070] The retaining wall structure 40 of Example 2 has the same effects as those of Example 1. In particular, the retaining wall structure 40 of Example 2 employs a configuration and construction method in which the front wall material 6 and the rear wall material 41 are connected via horizontal reinforcement members 53, and diagonal tie members 26 are attached not only to the front wall material 6 but also to the rear wall material 41, as shown in Figures 8(b) and (c).

[0071] By adopting such a configuration and construction method, the retaining wall structure 40 of Example 2 is configured to stand independently without leaning against the cut earth surface of mountainous areas by filling the backfill soil 17 on the rear side of the rear wall material 41, making it applicable even in areas other than mountainous areas.

[0072] Moreover, as described above, the fill soil 15 is independently erected, and is externally constrained and reinforced at its front, back, bottom and top by the front wall material 6, horizontal reinforcement material 53 and back wall material 41 in the lower and upper stages, so it has a large load-bearing capacity. Therefore, it can be applied to river bank protection works, etc., even in geographical conditions where there is no natural ground on the back side.

[0073] Example 3 A retaining wall structure and a construction method thereof according to a third embodiment of the present invention will be described with reference to Figures 10 to 12. A retaining wall structure 60 according to the third embodiment, the overall configuration of which is shown in Figure 10(b), utilizes the retaining wall structure 5 according to the first embodiment with other structures added thereto, and corresponds to a modified example of the first embodiment, so to speak.

[0074] FIG. 10(a) shows a mountainside 1 of natural ground on which Example 3 is to be constructed. This is suitable for construction on the front side of such a mountainside. For example, as shown in FIG. 12 as an example of the application of a retaining wall structure 60, this is applicable to support structures constructed on the sloping surface of natural ground to support from below a road 69 constructed in mountainous areas.

[0075] During construction, as shown in Fig. 10(b) (imaginary line in Fig. 10(a)), a steeply sloping cut surface 3 is formed on the lower side of the mountainside 1 of the natural ground, and a comparatively gently sloping cut surface 61 is formed on the upper side. Note that, if the mountainside 1 has a similarly gradual slope to the cut surface 61, the original mountainside 1 may be used without any special cutting surface 61 being formed.

[0076] The outline of the retaining wall structure 60 of Example 3 is that the stacked multi-tiered embankment structure consists of a lower group 64 formed on the front side of the lower steeply sloping cut surface 3 and an upper group 65 formed on the front side of the upper gently sloping cut surface 61, as shown in Figure 10(b).

[0077] The multiple stages of embankment structures 16 constituting the lower group 64 have the same configuration as in Example 1 as shown in Figures 10 to 12, and therefore a description thereof will be omitted. The multiple stages of embankment structures 66 constituting the upper group 65 have different configurations from those in Example 1.

[0078] In this way, the retaining wall structure 60 of Example 3 is a composite and leaning type retaining wall structure, consisting of multiple stages of embankment structures 16 constituting a lower group 64 of different configuration and multiple stages of embankment structures 66 constituting an upper group 65.

[0079] The upper group 65 of multiple-stage embankment structures 66, the configuration of which is shown in Figs. 10(b) and 12, is formed on the lower group 64 of multiple-stage embankment structures 16 as shown by imaginary lines in Figs. 11(a) and 11(b).

[0080] The multi-stage embankment structure 66 of the upper group 65 formed on the front side of the gently sloping cut face 61 each has a front wall material 6 and a horizontal reinforcement material 53 connected to the rear end of the bottom portion 8 of the front wall material 6, but does not have a rear wall material.

[0081] The front wall material 6 in the embankment structure 66 has the same configuration as the front wall material 6 in Example 1, and the horizontal reinforcement material 53 has the same configuration as the horizontal reinforcement material 53 in Example 2, and each is formed of expanded metal.

[0082] When constructing the lowest stage embankment structure 66 among the multiple stages of the upper group 65, the front wall material 6 is positioned on the front side of the upper surface (top surface of the fill soil 15) of the topmost stage embankment structure 16 among the multiple stages of the constructed lower group 64, as shown in Figure 11(a).

[0083] Then, the coil 20 is placed from below in the width direction on the rear end of the bottom portion 8 of the front wall material 6, and the front end of the horizontal reinforcement material 53 is placed on top of it. By inserting a connecting rod 21 into the coil 20, the front wall material 6 and the horizontal reinforcement material 53 are connected as shown in Figures 10(b) and 11(b).

[0084] As in the first embodiment, the diagonal tie members 26 and suction members 31 are attached to the front wall material 6. On top of the front wall material 6 and horizontal reinforcement members 53 thus arranged, fill soil 15 is poured together with crushed stone up to the upper end of the front wall material 6 and tamped down, as shown in Fig. 11(b). In this manner, the lowest-tier embankment structure 66 of the multiple tiers of embankment structures 66 in the upper group 65 is formed.

[0085] Using a similar process, a second tier of embankment structures 66 is formed on top of the lowest tier of embankment structures 66 of the upper group 65, as shown in Figure 11(b), and then, although not shown, multiple tiers of embankment structures 66 such as a third tier are stacked in sequence to form the retaining wall structure 60 of Example 3 as shown in Figures 10(b) and 12.

[0086] In the retaining wall structure 60 of Example 3, for the multiple-stage embankment structure 16 of the lower group 64 which is subjected to relatively high earth pressure, the fill soil 15 is wrapped and reinforced at its front, back, underside and top sides by the front wall material 6 and back wall material 11 of the upper and lower stages, as in Example 1, so as to have a large load-bearing capacity.

[0087] As for the multi-tiered embankment structure 66 of the upper group 65, which is formed in a space having a gentle slope in front of the upper cut surface 61 and a relatively wide area extending toward the rear side (depth direction) up to the upper cut surface 61, no rear wall material is provided, but the fill soil 15 is reinforced from the front, bottom and top by the front wall material 6 and horizontal reinforcement material 53.

[0088] In the retaining wall structure 60 of the third embodiment, the topmost embankment structure 66 of the upper group 65 has a wide upper surface extending back to the cut surface 61, facilitating sufficient compaction with a roller, and facilitating and economical construction work for a road 69 as shown in Fig. 12. It is suitable for mountain roads where it is desired to minimize excavation of cut soil.

[0089] The above describes the form for implementing the retaining wall structure and its construction method according to the present invention based on examples, but it goes without saying that the present invention is not limited to such examples, and there are various embodiments within the scope of the technical matters described in the claims. [Industrial Applicability]

[0090] The retaining wall structure and the construction method thereof according to the present invention can be used for retaining wall structures and construction methods thereof constructed in many places, such as mountainside retaining walls in mountainous areas, protective walls against falling rocks and collapsing soil, or river banks. [Explanation of symbols]

[0091] 1. The surface of a hillside in natural ground 2. Drilling Line 3 Cut surface 4 Bottom of cut surface 5 Retaining wall structures 6 Front wall material 7 Front part 8 Bottom part 11 Rear wall material 12 Bottom part 13 Back section 15 Filling soil 16 Embankment Structure 17 Backfill soil 20 Coil 21 Connecting rod 22 Connection structure 25 Wader material 26 Diagonal tie material 27 Top Hook 28 Bottom Hook 31 Suction prevention material 40 Retaining wall structures 41 Rear wall material 42 Embankment Structure 45 Rear part 46 Bottom part 49 Upper surface of embankment structure 50 Bottom of cut surface 53 Horizontal reinforcement 60 Retaining wall structures 61 Upper cut face 64 Lower group of multi-stage embankment structure 65 Upper group of multi-stage embankment structure 66 Upper group of embankment structures 69 Road

Claims

1. A method for constructing a retaining wall structure, comprising stacking embankment structures in multiple tiers, the embankment structures having front wall materials made of expanded metal and consisting of a bottom portion and a front portion extending upward from a front end of the bottom portion, and rear wall materials made of expanded metal and consisting of a bottom portion and a rear portion extending upward from a rear end of the bottom portion, For the first stage embankment structure, a coil is placed on the bottom of the front wall material from below, the bottom of the rear wall material is placed on top of it, a connecting rod is passed through the coil to connect the front wall material and the rear wall material, the coil is screwed into the upper part of the rear part of the rear wall material, the suction prevention material and the wale raising material extending horizontally in the width direction are attached to the front part of the front wall material by passing them through the upper end hook of the diagonal tie material, and the lower end hook of the diagonal tie material with the wale raising material passed through the upper end hook is hung on the bottom part of the front wall material, so that the diagonal tie material is hung between the front and bottom parts of the front wall material, backfill soil is filled between the rear wall material and the cut surface of the natural ground and compacted, and the space between the front wall material and the rear wall material is filled with fill soil and compacted, and construction is performed by The second and subsequent embankment structures are constructed in the same process as the first embankment structure, and the upper embankment structures are stacked in order to construct a retaining wall structure, A method for constructing a retaining wall structure, characterized in that when constructing an upper level embankment structure on a lower level embankment structure, the rear part of the upper level rear wall material is covered with a coil attached to the rear part of the lower level rear wall material and a connecting rod is inserted into the coil to connect the upper level rear wall material to the lower level rear wall material.

2. A method for constructing a retaining wall structure, comprising stacking multiple embankment structures having a front wall material formed from expanded metal and consisting of a bottom portion and a front portion extending upward from a front end of the bottom portion, and a back wall material formed from expanded metal and consisting of a bottom portion and a back end of the bottom portion extending upward from the back end of the bottom portion to construct a multiple-tiered embankment structure of a lower group, and stacking multiple embankment structures on top of the front wall material formed from expanded metal and consisting of a bottom portion and a front portion extending upward from the front end of the bottom portion, and consisting of horizontal reinforcement members formed from expanded metal to construct a multiple-tiered embankment structure of an upper group, For the first embankment structure in the lower group of multiple embankment structures, a coil is placed from below on the bottom surface of the front wall material, the bottom surface of the rear wall material is placed on top of it, and a connecting rod is passed through the coil to connect them, the coil is screwed into the upper part of the rear part of the rear wall material, the suction prevention material and the wale raising material extending horizontally in the width direction are attached to the front part of the front wall material by passing them through the upper end hook of the diagonal tie material, and the lower end hook of the diagonal tie material with the wale raising material passed through the upper end hook is hung on the bottom part of the front wall material, so that the diagonal tie material is hung between the front and bottom parts of the front wall material, backfill soil is filled between the rear wall material and the cut surface of the natural ground and compacted, and the space between the front wall material and the rear wall material is filled with fill soil and compacted, and construction is performed by The second and subsequent embankment structures are constructed in the same process as the first embankment structure, with the upper embankment structures being stacked in order, and the coil attached to the rear part of the rear wall material of the lower embankment structure is covered with the rear part of the rear wall material of the upper embankment structure, a connecting rod is inserted into the coil, and the rear wall material of the upper stage is connected to the rear wall material of the lower stage, and then the construction is completed. For the first stage of the embankment structure of the multiple stages of the upper group, a front wall material and horizontal reinforcement material are placed on the top surface of the embankment structure of the top stage of the multiple stages of the lower group, and connected with a coil and a connecting rod inserted into the coil. The suction prevention material and the waling material extending horizontally in the width direction are attached to the front part of the front wall material by passing them through the upper end hooks of the diagonal tie material, and the lower end hook of the diagonal tie material with the waling material passed through the upper end hook is hung on the bottom part of the front wall material, so that the diagonal tie material is hung between the front and bottom parts of the front wall material, and the space between the front wall material and the natural ground is filled with fill soil and compacted. A method for constructing a retaining wall structure, characterized in that the second and higher embankment structures of a multi-tiered embankment structure in the upper group are constructed in the same manner as the first tier of the embankment structure in the upper group, and the upper tier embankment structures are stacked in sequence.

3. A method for constructing a retaining structure, comprising stacking a plurality of layers of embankment structures each having a front wall material and a rear wall material formed from expanded metal, and filling and compacting fill soil between the front wall material and the rear wall material, A front wall material having a bottom surface and a front surface portion bent from the front end of the bottom surface upward and toward the rear side and formed into an approximately ∠-shaped shape in a side view, a belly-raising material is attached horizontally to the front surface so as to extend in the width direction, A plurality of diagonal tie members are attached between the front part and the bottom part at intervals in the width direction, with the upper ends of each of the diagonal tie members hanging on the flared member and the lower ends of each of the diagonal tie members hanging on the bottom part, A rear wall material having a bottom portion and a rear portion extending from a rear end of the bottom portion by being bent upward at an angle of approximately 90°, a flared material is attached horizontally to the rear portion of the rear wall material so as to extend in the width direction, and a plurality of diagonal tie materials are attached between the rear portion and the bottom portion at intervals in the width direction, with their upper ends hanging on the flared material and their lower ends hanging on the bottom portion, A coil extending in the width direction is attached to the upper end of the back part, The bottom portion of the front wall material is connected to a horizontal reinforcement material formed from expanded metal by a coil and a connecting rod inserted into the coil, and the bottom portion of the horizontal reinforcement material is connected to the rear wall material by a coil and a connecting rod inserted into the coil, thereby connecting the bottom portion of the front wall material and the bottom portion of the rear wall material via the horizontal reinforcement material, Among the multiple stages of embankment structures, a rear portion of a rear wall material of a lower stage embankment structure and a rear portion of a rear wall material of an upper stage embankment structure are connected by inserting a connecting rod through the rear portion of the upper stage embankment structure in a state in which the rear portion of the lower stage embankment structure is covered by a coil attached to the rear portion of the lower stage, A construction method for a retaining wall structure, characterized in that the fill soil of a lower-level embankment structure is restrained by the front wall material, horizontal reinforcement material and rear wall material of the lower-level embankment structure, and the front wall material, horizontal reinforcement material and rear wall material of the upper-level embankment structure.

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