JP2019056281A - Civil engineering structure - Google Patents

Abstract

To provide a civil engineering structure utilizing a bamboo reinforcing material with joints, which is treated with fumigation heat.SOLUTION: A reinforcing soil wall 1 being a civil engineering structure includes a retaining wall part 25 comprising multi-stepped embankment structures 3 constructed by heaping soil upon a bottom ground 2 sequentially. An L-shaped wall surface material 6 constituting a wall surface part 14 of the embankment structure 3, and a bamboo reinforcing material 11 having joints 29, at least one end of which is joined to the wall surface material 6 and which is treated with fumigation heat, are disposed on each of the upper surfaces of the bottom ground 2 and the multi-stepped embankment structure 3. The bamboo reinforcing materials 11 are arranged longitudinally from the front face toward the back face of the embankment structure 3, and laterally in multiple rows at regular intervals.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a civil engineering structure, and more particularly, to a civil engineering structure using a bamboo reinforcing material that has been subjected to smoke heat treatment, and a reinforced earth retaining wall, a dam, a earth retaining work, a valley The present invention relates to a civil engineering structure that can be applied to stop construction, road retaining walls, and the like.

  Conventionally, as a reinforced soil retaining wall, a wall surface material is provided on the wall surface side, and a laying net material (for example, geotegrid etc.) is laid in connection with the wall surface material. There is known a structure in which a banking structure in which banking is embedded is constructed from a plurality of stages sequentially from below (see Patent Documents 1 and 2).

  As a wall material, Patent Document 1 discloses a configuration in which an L-shaped wall material is used, and Patent Document 2 discloses a configuration in which a thinning material is used.

  In addition, as a soil retaining structure, there is a configuration in which a holding body (wall surface material) is provided on the wall surface side and embankment is embedded on the back side of the holding body, and the embankment structure is sequentially constructed in a plurality of stages from below. (See Patent Document 3).

  Patent Document 3 discloses a configuration in which a thinned log is used as a holding body, and further discloses that a thinned bamboo may be used instead of a thinned log. By providing the means, the retaining wall body on which loads such as earth pressure, water pressure, and inertial force during earthquakes are supported by the frictional resistance in the embankment, and the resistance of the retaining wall body against these loads is further strengthened. Is described.

  This anchor means is connected to a holding body between each embankment layer, but is laid and buried, and as a part of the anchor means, a chain-like tension member buried in the embankment so as to extend in the rear direction is provided. The provided configuration is disclosed.

  By the way, conventionally, a wood-based material drying apparatus that performs a smoke heat treatment for the purpose of drying a wood-based material such as wood and bamboo obtained by cutting in a short time is known (see Patent Document 4).

Japanese Patent Laid-Open No. 2004-250913 JP 2001-31172 A JP 2011-122355 A Japanese Patent No. 4074479

  In the conventional embankment structure, the strength of the embankment structure is increased by laying a laying net material such as a geogrid as shown in Patent Documents 1 and 2, or by arranging a strip-shaped reinforcing material using a steel material. , Geogrid, strip-shaped reinforcements using steel, etc., increase the material and construction costs.

  The tension member embedded in the embankment as a part of the anchor member so as to extend in the back direction as shown in Patent Document 3 is a chain, and is not formed but is formed of a metal chain. Conceivable. However, metal chains are expensive, and there is a problem that corrosion tends to occur when buried in the soil.

  On the other hand, bamboo is used for bamboo baskets, furniture, bamboo fences, biomass fuels, etc., but the amount used is limited. In recent years, bamboo forests have become devastated and contribute to earth and sand disasters. Therefore, it is desired to improve bamboo forests and use bamboo materials in various places.

  Bamboo has the same strength as cast iron, but it is prone to mold and insects.As a result, there is a problem that the durability is reduced due to corrosion. However, from the mechanical properties such as strength, the tensile strength is the same as that of wood. It is 2 to 5 times larger than that. Therefore, it may become a useful material depending on how to maintain such strength and enhance durability.

  By the way, conventionally, there are methods such as wet (caustic soda is put in hot water and boiled), dry (boil or fire), or injecting chemicals to prevent bamboo mold and insects. Among these, according to the durability test results (durability treatment test at the time of construction of the bamboo cage in Nagakute Japan Expo 2005 held by Ai-Etsuji), it was reported that the smoke heat treatment was most effective.

  The present invention solves the problems such as high cost and durability of the laying net material in Patent Documents 1 and 2 and the tension member as shown in Patent Document 3, and also promotes the use of bamboo materials to improve the bamboo forest. In order to solve the problem of devastation, the construction cost of civil engineering structures is reduced by using bamboo materials for civil engineering structures, and a civil engineering structure that improves strength and increases durability is realized. Is an issue.

  In order to solve the above-mentioned problem, the present invention is a civil engineering structure comprising a multi-stage embankment structure sequentially constructed on a bottom ground, and having a retaining wall portion, the bottom ground and a multi-stage embankment structure Provided to the body is a civil engineering structure characterized in that the smoke-heat treated split bamboo is arranged as a bamboo reinforcing material.

  In order to solve the above-mentioned problem, the present invention is a civil engineering structure comprising a multi-stage embankment structure sequentially constructed on a bottom ground, and having a retaining wall portion, the bottom ground and a multi-stage embankment structure The embankment structure excluding the uppermost embankment structure in the body has an L-shaped or eaves-shaped wall material constituting the wall surface portion of the embankment structure disposed on its upper surface, and is subjected to smoke heat treatment A plurality of rows of bamboo reinforcing materials having nodes are arranged, and the bamboo reinforcing material is a split bamboo having a curved concave portion in which a circular bamboo having an annular cross section is vertically split at an equal angle in the annular direction. Each of the ground and the multi-level embankment structure is arranged with the curved concave portion facing upward and fixed with anchors, and the plurality of rows of bamboo reinforcing materials are respectively arranged in the longitudinal direction of the embankment structure from the position of the wall material. To go from the front side to the back side only, and Providing civil structures, characterized in that independently of each other in a direction that is configurations that are arranged in parallel at intervals.

  The civil engineering structure has a structure including a retaining wall portion only on the front side, and the lengths of the plurality of rows of bamboo reinforcing materials arranged on the bottom ground and each of the multi-level embankment structures are the same, The length is preferably longer when the wall height of the civil engineering structure is higher.

  The civil engineering structure has a structure including retaining walls on both sides of the front side and the back side, and the plurality of rows of bamboo reinforcements arranged on the bottom ground and each of the multi-level embankment structure are on the front side. It is preferable that it is the structure arrange | positioned from the position of the wall surface material of a retaining wall part over the position of the wall surface material of the retaining wall part of a back side.

According to the present invention, the following effects are produced.
(1) Since the reinforced bamboo material subjected to smoke heat treatment is arranged in a plurality of embankment structures constituting the civil engineering structure, the strength and stability of the entire civil engineering structure can be increased, and the durability can be enhanced.

(2) The use of reinforced bamboo material that has been smoke-heat treated to reinforce the embankment structure reduces the construction cost of civil engineering structures compared to the case of using a grid material such as geogrid or metal chain material. It also helps to promote the use of bamboo materials and the maintenance of bamboo forests.

It is a perspective view for demonstrating the reinforced earth wall which is Example 1 of the civil engineering structure which concerns on this invention. It is sectional drawing of the reinforced earth wall of the said Example 1. FIG. (A) is an enlarged view for explaining the main part of FIG. 2 (particularly the wall surface part of the embankment structure), and (b) and (c) are postures arranged on the upper surface of the bottom ground (the embankment structure of each step). It is a figure which shows the reinforcement | strengthening bamboo material in, (b) It is a top view, The figure on the left side of (c) is a front view, The figure on the right side is a side view. (A) is a front view of the wall surface part of a banking structure, (b) is a top view of a wall surface material, slant tie material, and a reinforced bamboo material. It is a perspective view for demonstrating the dam which is Example 2 of the civil engineering structure which concerns on this invention. It is sectional drawing orthogonal to the upstream and downstream direction of the dam of the said Example 2. FIG. It is a figure which shows the result of the drawing test of a bamboo reinforcement, (a) shows the relationship between drawing force and displacement, (b) is a figure which shows the friction coefficient obtained from the drawing test.

  EMBODIMENT OF THE INVENTION The form for implementing the civil engineering structure which concerns on this invention is demonstrated below with reference to drawings based on an Example.

Example 1
The civil engineering structure according to the present invention is constructed by stacking a plurality of embankment structures, and is a reinforced earth wall, dams, earth retaining works, valleys in projects such as forest restoration, various dams, sabo, road construction, etc. It can be applied to stop construction and road retaining walls.

  In Example 1, a structure in which a civil engineering structure according to the present invention is applied to a reinforced earth wall will be described with reference to FIGS. Therefore, the civil engineering structure in Example 1 is a reinforced earth wall 1 having a configuration as shown in FIGS.

  In Example 1, the reinforced earth wall 1 constructed along the natural ground surface 4 (see FIG. 2) is viewed from the front, the front side (front side) is the front side, and the back side (back side) is the rear side. The front-rear direction is also referred to as the “depth direction”, and the left-right direction is also referred to as the “lateral direction”.

  Hereinafter, for each of the bottom ground 2 which becomes the base of the reinforced soil wall 1 and the plurality of banking structures 3 (except for the uppermost banking structure 3) which are sequentially constructed on the bottom ground 2, an L-shape is formed thereon. A configuration in which members such as the wall surface material 6, the diagonal tie material 7, the earth and sand suction prevention mat 10, and the bamboo reinforcing material 11 are arranged will be described.

  About the bottom ground 2 and the multi-level embankment structure 3, the wall material 6, the slant tie material 7, the earth and sand suck-out prevention mat 10, the bamboo reinforcement material 11, etc. of the same structure are arrange | positioned on the upper surface, respectively, and it is the embankment 12 after that. The embankment structure 3 is constructed by filling (inner filling) with earth and sand.

  In short, the multi-stage embankment structures 3 sequentially constructed on the bottom ground 2 have basically the same configuration. Therefore, hereinafter, the object on which the wall surface material 6, the diagonal tie material 7, the earth and sand suction prevention mat 10, the bamboo reinforcing material 11, and the like are arranged is described as “bottom surface ground 2 (banking structure 3 of each step)”.

  In order to construct the wall surface portion 14 of the embankment structure 3 on the front end portion of the bottom ground 2 (the embankment structure 3 of each step), as shown in FIGS. 1, 2, and 3A, a wall surface material is used. 6 is arranged such that its longitudinal direction is in the lateral direction.

  As shown in FIG. 2 and FIG. 3A, the wall surface material 6 has a substantially L-shaped cross section perpendicular to the longitudinal direction, and includes a bottom surface portion (horizontal portion) 15 and a front surface portion (standing portion) 16. The bottom surface part 15 is placed on the bottom surface ground 2 (the embankment structure 3 of each step).

  Normally, a rigid expanded metal, a wire mesh, or the like is used as the wall surface material 6, but the first embodiment shows an example in which a rigid expanded metal is used. A plurality of wall materials 6 are continuously arranged in accordance with the width (lateral width) of the entire reinforced earth wall 1 to be constructed.

  As shown in FIGS. 1, 2, 3 (a) and 4 (b), an oblique tie material 7 is attached between the bottom surface portion 15 and the front surface portion 16 of the wall surface material 6. As shown in FIG. 3A, the lower end portion and the upper end portion of the diagonal tie material 7 are folded back to form a lower folded portion 19 and an upper folded portion 20, respectively. The lower folded portion 19 of the diagonal tie material 7 is engaged with and attached to the bottom surface portion 15 of the wall surface material 6.

  The upper folded portion 20 of the slanted tie material 7 projects forward through the front surface portion 16 of the wall surface material 6, and the projected portion has an axial shape as shown in FIGS. 3 (a) and 4 (a). The urging member 21 is inserted horizontally and laterally.

  A plurality of wall surface materials continuously arranged in the horizontal direction by inserting the urging material 21 through the upper folded portions 20 of the plurality of oblique tie materials 7 continuously arranged in the horizontal direction along the ground surface 4. 6 are arranged in alignment.

  The wall materials 6 adjacent in the lateral direction are connected to each other by a binding band 23 as shown in FIG. As shown in FIG. 2, the wall surface material 6 and the wall surface portion 14 of the multi-level embankment structure 3 are arranged rearward little by little as going to the upper level. Thereby, in the reinforced earth wall 1, the retaining wall part 25 slightly inclined upward and rearward as a whole is formed.

  As shown in FIG. 2 and FIG. 3A, the earth and sand suction preventing mat 10 is attached along the back surface of the wall surface material 6. The earth and sand suction prevention mat 10 is attached from the back surface of the front surface portion 16 of the wall surface material 6 to the front side of the bottom surface portion 15.

  The upper end portion of the earth and sand suck-out prevention mat 10 is arranged so as to be above the wall surface material 6, and the earth and sand are filled and the embankment 12 is formed, and then is folded over the front end portion of the embankment 12. The earth and sand suction prevention mat 10 has a function of making it difficult for the earth and sand (filled earth and sand) constituting the embankment structure 3 to flow out from the front surface portion 16 of the wall surface material 6.

  In addition, the earth and sand suction prevention mat 10 extends in the depth direction from the top surface 15 of the wall surface material 6 toward the cut slope 26 of the backside of the mountain 4 and the bottom ground 2 (the embankment structure 3 of each step). It may be laid on the top. Moreover, it is good also as a structure extended from the bottom ground 2 (the embankment structure 3 of each step | paragraph) further along the cut inclined surface 26, and filling the earth and sand of the embankment 12 in a bagging form.

  As shown in FIGS. 1, 2, 3 (a), and 4 (b), the present invention is characterized by bamboo reinforcement that has been subjected to smoke heat treatment on the bottom ground 2 (the embankment structure 3 at each stage). The material 11 has a plurality of rows, each of which has a longitudinal direction extending from the front side to the back side of the embankment structure 3 and is connected to each other in the lateral direction and is not constrained and restrained independently. This is a configuration arranged in parallel with reference to FIG. Here, “independently” refers to a configuration in which the plurality of rows of bamboo reinforcement members 11 arranged in parallel are not connected to each other in the lateral direction (for example, a lattice-like configuration).

  In particular, in the present invention, it is important to use the bamboo reinforcing material 11 that has been subjected to smoke heat treatment. As described above, the bamboo reinforcing material not subjected to the smoke heat treatment is corroded by mold and insects in the soil and has poor durability. However, in the present invention, the bamboo reinforcing material 11 subjected to the smoke heat treatment is used. By adopting, the durability could be greatly improved.

  Conventionally, in the civil engineering structure technology, even if there is a technology of using bamboo as a reinforcing material, in particular, “bamboo subjected to smoke heat treatment” is arranged on the embankment structure as in the present invention to reinforce the bamboo. There was no idea of using it in the soil as a material. Thereby, as will be described later, not only the reinforcing function but also the remarkable effect is produced in terms of improving the durability.

  The bamboo reinforcing material 11 is divided into four round bamboos subjected to smoke heat treatment, that is, round bamboos having a circular cross section are divided vertically (along the longitudinal direction) at intervals of 90 degrees in the annular direction, The split bamboo manufactured as four members having a 90-degree curved cross section is used.

  The width of the bamboo reinforcing material 11 formed by dividing the round bamboo into four is, for example, approximately 70 mm. As shown in FIGS. 3B and 3C, the bamboo reinforcing material 11 is arranged on the bottom ground 2 (the embankment structure 3 at each stage) with the curved recess 13 facing upward. Thereby, the earth and sand to be the embankment 12 is sufficiently filled in the curved recess 13, so that it is firmly embedded in the embankment 12 and the frictional force with the embankment 12 is also increased.

  In addition, the bamboo reinforcing material 11 is used in a state where the nodes are left intact and utilized without the process of scraping off the original nodes of the bamboo. In short, in the civil engineering structure of the present invention, as shown in FIGS. 3A to 3C and FIG. 4B, the bamboo reinforcing material 11 having the nodes 29 is used.

  The node 29 has a swelling portion 30 on the outer surface side and a partition wall portion 32 on the inner surface side. As will be described later, the bamboo reinforcing material 11 having this node 29 is pulled and bent in the embankment structure 3. The embankment structure 3 by increasing the frictional force with the earth and sand of the embankment 12, increasing the pulling resistance, preventing the wall material 6 from collapsing, reducing the shear in the shearing direction in the embankment 12, etc. Increase the strength.

  The bamboo reinforcing material 11 is disposed on the bottom surface ground 2 (the embankment structure 3 of each step), and in particular, the front end side of the bamboo reinforcing material 11 is disposed on the bottom surface portion 15 of the wall surface material 6 and the bamboo reinforcing material. 11 is disposed up to the position of the back surface of the wall surface material 6.

  A through hole (not shown) is formed in the bamboo reinforcing material 11, and the bamboo reinforcing material 11 is shown in FIGS. 2, 3 (a), and 4 (b) by a reinforcing bar anchor 31 through the hole. Moreover, it is being fixed on the bottom ground 2 (the embankment structure 3 of each step). Thereby, the bamboo reinforcing material 11 is prevented from moving when the earth and sand as the embankment 12 is scattered and filled on the bottom ground 2 (the embankment structure 3 of each step).

  Bamboo reinforcements 11 are arranged in the depth direction in the depth direction on the bottom surface 2 and the multi-level embankment structure 3. The length L of each of the plurality of rows of bamboo reinforcements 11 is the bottom surface 2. In addition, the embankment structures 3 of the plurality of stages are not different from each other, but are the same as each other, or the embankment structures 3 belonging to the upper half of the entire reinforcing earth wall 1 (hereinafter simply referred to as “upper half”) are long. However, the embankment structure 3 (hereinafter simply referred to as “lower half”) belonging to the lower half may be shortened. However, the length L (see FIG. 4B) of the bamboo reinforcing material 11 is made different depending on the height of the reinforced soil wall 1 (wall height H, see FIG. 2).

  In short, when the wall height H of the reinforced earth wall 1 is higher, the reinforced earth wall 1 is required to have a higher strength. Therefore, a longer bamboo reinforcing material or a plurality of bamboo reinforcing materials should be used for each of the plurality of rows. It is necessary to make the length L of the bamboo reinforcing material 11 longer by connecting them together.

  As a guideline, when the wall height H of the reinforced earth wall 1 is approximately 3 m or less, the length L is 2 m, and when the wall height H is approximately 3 to 6 m, the length L is 3 m and the wall height H is approximately 6 to In the case of 8 m, the length L of the bamboo reinforcing material 11 is 3 m in the lower half and 5 m in the upper half. That is, when the wall height H of the reinforced earth wall 1 is 3 m, the bamboo reinforcing material 11 having a length L of 2 m is arranged in the depth direction on the bottom ground 2 and the multilevel embankment structure 3.

  If the length of the bamboo reinforcing material 11 is sufficient, it is preferable to use a single material to save time and labor, but if the required length is not satisfied, a plurality of bamboo reinforcing materials 11 are arranged in the longitudinal direction. You can connect them together. For example, when the wall height H exceeds 8 m and the length L of the bamboo reinforcing material 11 exceeds 5 m, a plurality of bamboo reinforcing materials 11 may be connected and used.

  In this way, when the bamboo reinforcing material 11 must be connected, the bamboo reinforcing materials adjacent to each other in the longitudinal direction to be connected are arranged so as to be doubled in the longitudinal direction. For example, two bamboo reinforcing materials 11 adjacent to each other in the longitudinal direction to be connected are overlapped 2 m above and below in the longitudinal direction, and the overlapping portions are connected with bolts and nuts. Connect them by tying them with cable ties.

  In the configuration of doubling the arrangement, the two bamboo reinforcing materials 11 adjacent to each other in the longitudinal direction, as described above, are simply laid out side by side by doubling in the longitudinal direction by 2 m, without being superposed vertically by 2 m. Just be fine.

  As described above, the bamboo reinforcements 11 are arranged in a plurality of rows on the bottom ground 2 (the embankment structure 3 of each step) with the longitudinal direction thereof being directed in the front-rear direction and with a constant interval W in the lateral direction. Although they are arranged independently and parallel to each other (see FIG. 4B), the interval W is, for example, 4 per 1 m, that is, an equal interval of approximately 25 cm.

  The bottom surface ground 2 (the embankment structure 3 of each step) on which the wall surface material 6, the diagonal tie material 7, the earth and sand suction prevention mat 10, the bamboo reinforcing material 11, etc., which are disposed as described above, are respectively disposed thereon. The embankment structure 3 is formed by filling the sand up to the height of the substantially upper end of the wall material 6. Such embankment structures 3 are stacked in a plurality of stages and sequentially upward, whereby the reinforced earth wall 1 including the plurality of embankment structures 3 is constructed.

  In addition, in the civil engineering structure according to the present invention, what is filled as the embankment 12 is its use (reinforced earth wall, dam, road retaining wall, earth retaining work, valley stop work, etc.), required function, construction site Depending on various conditions such as fillers available in the vicinity, it may be soil, earth and sand, gravel, stone (eg, cracked stone), concrete material, etc., or a mixture thereof.

(Function)
As described above, the reinforced earth wall 1 which is the first embodiment of the civil engineering structure according to the present invention has the wall surface material 6, the diagonal tie material 7, and the prevention of earth and sand sucking on the bottom ground 2 (the embankment structure 3 of each step). The mat 10, the bamboo reinforcing material 11, and the like are arranged, and the construction process and operation thereof will be further described below.

  First, the wall surface material 6, the diagonal tie material 7, the earth and sand suction prevention mat 10, etc. are arranged on the bottom ground 2 as described above. Further, the bamboo reinforcing materials 11 are arranged in a plurality of rows, the front ends thereof being the positions of the back surface of the wall surface material 6, and the longitudinal direction thereof is directed to the back surface side, with a certain interval in the lateral direction, independently of each other. And it arrange | positions on the bottom ground 2 from the bottom face part 15 of the wall surface material 6, and is fixed with the reinforcing bar anchor 31, as shown to FIG. 2, FIG.

  And the earth and sand which is the embankment 12 is sprinkled and filled to the height of the substantially upper end of the wall surface material 6 provided on the bottom ground 2, and the 1st embankment structure 3 is constructed | assembled.

  Then, as in the case of the bottom ground 2, the wall surface material 6, the slanted tie material 7, the earth and sand suction prevention mat 10, the bamboo reinforcing material 11, and the like are disposed on the first-stage embankment structure 3. The earth and sand that is the embankment 12 are scattered and filled up to the height of the upper end of the material 6 to construct the second-stage embankment structure 3.

  Similarly, the wall material 6, the diagonal tie material 7, the earth and sand suction prevention mat 10, the bamboo reinforcing material 11, and the like are arranged on the lower level banking structure 3, and then the upper level banking structure 3. And a reinforced soil wall 1 composed of a banking structure 3 having a predetermined number of steps is constructed.

  The most characteristic feature of the reinforced earth wall 1 of the present invention is that the bamboo reinforcing material 11 subjected to smoke heat treatment is used as the bamboo reinforcing material 11. As a result, the bamboo reinforcing material 11 has an improved mold and insect repellent performance, and even when placed in the embankment 12, the durability is remarkably improved and the function of increasing the structural strength of the reinforced soil wall 1 is maintained for a long time. It becomes possible to do.

  Furthermore, since bamboo materials are abundant in Japan and can be obtained in large quantities at a low price even after smoke heat treatment, even if the bamboo reinforcing material 11 is used in a large amount for the embankment structure 3, the reinforcing earth wall 1 The construction cost is lower than that when a steel reinforcing material (eg, expanded metal), geogrid, or the like is used for the embankment structure 3.

  The reinforced soil wall 1 of the first embodiment is a bamboo reinforced heat-treated with smoke heat treatment on the bottom ground 2 and each embankment structure 3 in the depth direction and in parallel with a certain interval W in the lateral direction. Since the materials 11 are arranged in a plurality of rows, a drag force is generated against the vertical soil pressure generated in the embankment 12, and a reinforcing function against the vertical force applied to the embankment 12 is exhibited.

  Further, since the bamboo reinforcing material 11 moves relative to the embankment 12 in the longitudinal direction, a frictional force is generated at the contact interface over the length direction of the embankment 12 and the bamboo reinforcing material 11, so that the resistance force is increased. Arise. Therefore, it suppresses that the bamboo reinforcement 11 moves relatively with respect to the embankment 12 in the longitudinal direction.

  Since the bamboo reinforcing material 11 is arranged with the curved concave portion 13 facing upward, when the earth and sand to be the embankment 12 are scattered and filled from above, sufficient amount of earth and sand is placed in the curved concave portion 13 arranged upward. Therefore, the earth pressure in the lower direction is increased, the pad is firmly embedded in the embankment 12, the contact area of the bamboo reinforcing material 11 with the embankment 12 is increased, and the frictional force with the embankment 12 is increased. .

  If the curved concave portion 13 is arranged downward or sideways, even if the earth and sand that becomes the embankment 12 is scattered from above, the curved concave portion 13 directed downward is not sufficiently filled with earth and sand. Since the earth pressure of 12 is not sufficient for the bamboo reinforcement 11, it is difficult to embed it firmly.

  Moreover, the bamboo reinforcing material 11 into which the round bamboo is divided into four has nodes 29 at substantially equal intervals (30 to 40 cm) in the longitudinal direction. This node 29 serves as a so-called rib and increases the strength against the external force in the bending and pulling directions applied to the bamboo reinforcing material 11 and increases the frictional resistance against the embankment 12 by the swelling portion 30 and the partition wall portion 32 of the node 29, Resistance (extraction resistance) to relative movement in the longitudinal direction of the bamboo reinforcing material 11 in the embankment 12 is increased.

  Therefore, the strength of the reinforcing earth wall 1 against the external force in the vertical direction and the lateral direction (shear direction) applied to the embankment structure 3 due to an earthquake, wind and rain, etc. by the configuration in which the bamboo reinforcing material 11 is arranged on the embankment structure 3. The stability of the entire reinforced soil wall 1 can be increased.

  Further, an external force is applied to the wall surface material 6 by the earth pressure of the embankment 12, but since the bamboo reinforcing material 11 is provided, the embankment structure is formed by its relative tensile strength and pulling resistance with respect to the embankment 12. 3 wall surface material 6 and wall surface part 14 become difficult to collapse.

  By the way, as for the reinforced earth wall 1, the external force added to the front-back direction rather than the horizontal direction influences collapse more. Therefore, the bamboo reinforcing material 11 is arranged only in the front-rear direction, thereby exerting its frictional force in the front-rear direction and reinforcing the strength in the front-rear direction.

  Therefore, it is not necessary to have a complicated configuration in which the bamboo reinforcing material 11 is arranged in the horizontal direction in addition to the front-rear direction and joined in a lattice shape, and the bamboo reinforcing material 11 is simply directed in a plurality of rows, only in the front-rear direction, and horizontally. Since it suffices to arrange a certain interval in the direction independently, the configuration is simple, the construction work is simplified, and the material and the construction cost can be reduced.

(Comparison with existing reinforcement)
Here, the present inventor has compared the strength and cost of the bamboo reinforcing material subjected to the smoke heat treatment used in Example 1 and the existing reinforcing material Geogrid and steel reinforcing material (expanded metal). Is shown in Table 1.

  According to Table 1, the smoke-treated bamboo reinforcement has half the cost, although it has the same or better strength than the existing geogrid and steel reinforcement (expanded metal). It can be seen that the civil engineering structure according to the present invention is extremely useful and economical.

(Bamboo reinforcement pulling characteristic test)
In order to confirm the drawing characteristics of bamboo reinforcement, a pull-out test was conducted at Osaka Industrial Technology Research Institute.

In this pull-out test, Toyoura standard sand (φ = 38 °, c = 0.0 kN / m ² ) is used as the embankment material, and a thick split bamboo with a width of 50 mm is installed in the center of the compacted soil tank. After loading a predetermined upper pressure, a pulling force was applied by constant speed displacement control at 1.0 mm / min.

Normal stress σ = 29.5kN / ^{m 2} is an upper No圧, σ = 59.3kN / ^{m 2,} for σ = 89.5kN / ^{m 2} of 3 cases, pulling force obtained by pulling test P and withdrawal displacement δ This relationship is shown in FIG.

  From this result, the maximum shear stress on the upper and lower surfaces of the reinforcing material and the soil is obtained and converted into a friction coefficient, as shown in FIG. 7B, which is much higher than the true friction coefficient f = tanφ. It could be confirmed.

(Example 2)
Example 2 of the civil engineering structure according to the present invention will be described with reference to FIGS. In Example 2, a dam having a retaining wall portion on each of the front side and the back side will be described as a civil engineering structure.

  As a dam with retaining walls on both sides, here it is applied to various dams, such as water storage dams, intake dams, sabo / healing dams, with downstream retaining walls 36 and upstream retaining walls 37. Explain the dam.

  In Example 2, the front side is the downstream side, and the back side is the upstream side. In other words, when viewing the downstream retaining wall portion 36 from the front, the front side is the front side (front side) and the back side is the back side (rear side). The front-rear direction is also referred to as “depth direction”, and the left-right direction is also referred to as “lateral direction”.

  The dam 35 of the second embodiment is a structure in which a plurality of levels of the embankment structure 3 are sequentially stacked on the bottom ground 2, and bamboo that has been subjected to smoke heat treatment on each of the bottom ground 2 and the plurality of levels of the embankment structure 3. The characteristic configuration of the civil engineering structure according to the present invention, such as the configuration in which the reinforcing members 11 are arranged in a plurality of rows, is substantially the same as that of the first embodiment. Therefore, hereinafter, the dam 35 of the second embodiment will be described focusing on the configuration different from the reinforced earth wall 1 of the first embodiment.

  As shown in FIGS. 5 and 6, the dam 35 of the second embodiment has a downstream side retaining wall portion 36 and an upstream side retaining wall portion 37, respectively, facing upward (rear side (upstream side)) and front side (downstream side). ) And the overall configuration is different from that of the reinforcing earth wall 1 of the first embodiment in that the vertical cross section perpendicular to the lateral direction is trapezoidal.

  In the dam 35, in the bottom ground 2 (the embankment structure 3 of each step), a downstream side wall member 40 and an upstream side wall member 41 having a cross-sectional saddle shape are arranged at the front end and the rear end, respectively. A downstream side wall surface portion 44 and an upstream side wall surface portion 45 of the embankment structure 3 are formed.

  The downstream side wall surface portion 44 and the upstream side wall surface portion 45 are inclined upward and toward the rear side and the front side, respectively, and by the downstream side wall surface portion 44 and the upstream side wall surface portion 45 of the multi-stage embankment structure 3, As described above, the inclined downstream retaining wall portion 36 and the upstream retaining wall portion 37 are configured.

  The dam 35 is slightly different in structure from the reinforced earth wall 1 due to the difference in its use, but the structures of the downstream side retaining wall part 36 and the upstream side retaining wall part 37 are the same as those of the reinforced earth wall 1 of Example 1. The configuration of the wall portion 25 is substantially the same.

  Specifically, with respect to the downstream side wall surface portion 44 and the upstream side wall surface portion 45 of the dam 35 of the second embodiment, the downstream side and upstream side wall surface materials 40 and 41 on the bottom surface ground 2 (the embankment structure 3 of each step). The slanted tie material 7, the earth and sand suck-out preventing mat 10, the bamboo reinforcing material 11 and the like are arranged, and the earth and sand to be the embankment 12 are scattered and filled from above.

  In this dam 35, a sabo / healing dam that can be discharged from the top of the top embankment structure 3 is used as an application example, but the top embankment structure 3 becomes a water discharge channel, and as shown in FIG. A concrete layer 46 is formed corresponding to 12.

  In the downstream retaining wall portion 36 located below the downstream side of the water discharge channel, a space of about 50 cm between the embankment 12 and the downstream side wall surface material 40 is filled with the split stones 49, and the water discharge wall surface 50. Is formed. The falling water discharged through the discharge channel flows down downstream along or against the discharge channel wall surface 50.

  The drainage channel wall surface 50 is easily eroded by falling water. However, the drainage channel 49 is provided with a cracked stone 49, and the earth and sand suction prevention mat 10 is attached along the back of the cracked stone layer (a layer composed of the cracked stone 49). The wall surface 50 is protected so that the earth and sand of the embankment 12 is less likely to be sucked out (bottom-out) to the downstream side through the downstream side wall face material 40 even when water falls.

  As for the dam 35 of the second embodiment, similarly to the reinforced earth wall 1 of the first embodiment, the bamboo reinforcing material 11 has a plurality of rows in the longitudinal direction from the front side (downstream side) to the back side (upstream side) of the dam 35. And in parallel with a certain interval W in the lateral direction.

  In the dam 35 of the second embodiment, the smoke reinforcing heat-treated bamboo reinforcing material 11 has a bottom ground surface 2 (so that the front end and the rear end of the plurality of rows extend to the back surfaces of the downstream side wall face material 40 and the upstream side wall face material 41, respectively. On the embankment structure 3) of each step, the curved recess 13 is arranged facing upward. In other words, the bamboo reinforcing material 11 disposed on the bottom ground surface 2 (the embankment structure 3 of each step) is disposed between the downstream side wall surface material 40 and the upstream side wall surface material 41.

  In the reinforced earth wall 1 of the first embodiment, the length L of the plurality of rows of bamboo reinforcing members 11 respectively disposed in the bottom ground 2 and the plurality of embankment structures 3 are the same as each other. And the length L was the structure made to differ according to the whole height (wall height H) of the dam 35. FIG.

  However, in the dam 35 of the second embodiment, the length L of the plurality of rows of bamboo reinforcing members 11 is arranged between the downstream side wall surface material 40 and the upstream side wall surface material 41, respectively. The interval between the side wall face members 41 is substantially the same.

  In other words, the length L of the bamboo reinforcing material 11 is determined according to the width in the front-rear direction (the width from the downstream side to the upstream side) of the bottom ground 2 and the embankment structure 3 of each step. Therefore, the length L of the bamboo reinforcing material 11 differs depending on the width in the front-rear direction of the bottom ground surface 2 and the plurality of embankment structures 3 respectively disposed.

  In this way, a plurality of rows of bamboo reinforcing materials 11 subjected to smoke heat treatment are arranged in each of the bottom ground 2 and the plurality of embankment structures 3, and in the same manner as in the case of the reinforced soil wall 1 of Example 1, a plurality of The intensity | strength with respect to the force of the up-down direction and a horizontal direction (shear direction) added to each of the embankment structure 3 increases. For this reason, the embankment structure 3 or the dam 35 as a whole has increased strength and stability.

  In particular, the bamboo reinforcing material 11 disposed on the bottom ground 2 (the embankment structure 3 of each step) has a high tensile strength, and as described above, a pulling resistance is generated in the embankment 12 by the nodes 29, and the bamboo Since the reinforcing member 11 is arranged so that the front and rear ends thereof extend to the positions of the downstream side wall surface portion 44 and the upstream side wall surface portion 45, respectively, the width of the dam 35 in the front-rear direction (downstream side to upstream side) The strength increases throughout.

  Also, in the dam 35 of the second embodiment, the bamboo reinforcing material 11 is subjected to the smoke heat treatment, so that the durability is improved as in the case of the reinforced soil wall 1 of the first embodiment and is disposed in the embankment 12. However, the function can be maintained for a long time.

  As mentioned above, although the form for implementing the civil engineering structure which concerns on this invention was demonstrated based on Example 1 and Example 2, this invention is not limited to such an Example, Claim It goes without saying that there are various embodiments within the scope of the technical matters described in.

  Since the civil engineering structure according to the present invention has the above-described configuration, it can be applied to various civil engineering structures such as reinforced earth walls, dams, earth retaining works, valley retaining works, road retaining walls, and construction site retaining walls. .

1 Reinforced earth wall
2 Bottom ground
3 Embankment structure 4 Hill surface
6 Wall materials
7 Diagonal Thai
10 Sediment suction prevention mat
11 Bamboo reinforcement
12 Embankment 13 Curved recess of bamboo reinforcement
14 Wall part of embankment structure
15 Bottom (horizontal)
16 Front part (standing part)
19 Lower folded part 20 Upper folded part
21 Upset material
23 Tying Band
25 Retaining wall
26 Cut ground slope of Shizan
29 Bamboo reinforcement section
30 Nodal swelling 31 Reinforcing bar anchor
32 bulkheads
35 Weir
36 Downstream retaining wall
37 Upstream retaining wall
40 Downstream side wall face material
41 Upper side wall face material
44 Downstream side wall surface
45 Upstream side wall
46 Concrete layer 49 Split chestnut stone 50

Claims (4)

It is a civil engineering structure consisting of a multi-stage embankment structure constructed sequentially on the bottom ground, with a retaining wall,
A civil engineering structure, characterized in that the bottom ground and the multi-level embankment structure have a structure in which split bamboo subjected to smoke heat treatment is arranged as a bamboo reinforcing material. It is a civil engineering structure consisting of a multi-stage embankment structure constructed sequentially on the bottom ground, with a retaining wall,
In the embankment structure excluding the uppermost embankment structure among the bottom ground and the multi-stage embankment structure, an L-shaped or saddle-shaped wall material constituting the wall surface portion of the embankment structure is arranged on the upper surface. In addition, a plurality of rows of bamboo reinforcing materials that have been subjected to smoke heat treatment and have knots are arranged, and the bamboo reinforcing material has a curved concave portion formed by dividing a circular bamboo with a circular cross section in the vertical direction at an equal angle in the annular direction. It has split bamboo, and is arranged on the bottom ground and the multi-level embankment structure with the curved recess facing upward and fixed with anchors,
The multiple rows of bamboo reinforcements are arranged in parallel so that the longitudinal direction thereof is directed only from the position of the wall surface material to the direction from the front side to the back side of the embankment structure, and independently from each other in the lateral direction. The civil engineering structure characterized by having the structure made.   The civil engineering structure has a structure with a retaining wall only on the front side, and the lengths of the plurality of rows of bamboo reinforcements arranged on the bottom ground and each of the multi-level embankment structures are the same or upper half. The civil engineering structure according to claim 2, wherein the length of the civil engineering structure is longer when the wall height of the civil engineering structure is higher. .   The civil engineering structure has a structure including retaining walls on both sides of the front side and the back side, and the plurality of rows of bamboo reinforcements arranged on the bottom ground and each of the multi-level embankment structure are on the front side. The civil engineering structure according to claim 3, wherein the civil engineering structure is configured to be arranged from a position of the wall surface material of the retaining wall portion to a position of the wall surface material of the retaining wall portion on the back side.