JP2012184551A - Retaining wall block - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a retaining wall block of precast concrete, which is uniformly filled with filling material and has sufficient resistance to soil pressure, so that a retaining wall having high stability and excellent power balance can be constructed.SOLUTION: A retaining wall block (1) comprises a front face part (2) which is to be exposed to the surface of a retaining wall to be constructed, a rear face part (3) which is to be buried, and a pair of binding parts (5, 6) which connect the front face part (2) and the rear face part (3). The rear face part (3) has a height lower than that of the front face part (2). A central opening part (7) to be filled with filling material is defined by the front face part (2), the rear face part (3), and the pair of binding parts (5, 6), having an approximately circular or approximately elliptical upper surface shape. A space part (9) to be filled with filling material is defined by two neighboring retaining wall blocks (1, 1) of a plurality of the retaining wall blocks (1, 1,...) laid side-by-side in lateral direction, also having an approximately circular or approximately elliptical upper surface shape.

Description

  The present invention is arranged in a horizontal direction along slopes such as cut and embankment and stacked in a plurality of stages in the height direction, and inside of these is filled with filling materials such as crushed stones and chestnuts. The present invention relates to a retaining wall block made of precast concrete for which a retaining wall is constructed.

  In civil engineering work such as residential land creation, road construction, and railroad laying, so-called cutting work that excavates the ground higher than the surroundings, so-called embankment work that raises and raises the earth and sand to the ground, etc. is performed. Steep slopes formed by cutting, embankment, etc. are easy to collapse due to rainfall or earthquake. Therefore, a retaining wall which is a wall-like civil engineering structure is provided on such a slope. Some types of retaining walls are constructed in such a way that reinforcing bars are assembled at the construction site, and concrete is cast and formed integrally with the slope, or a standardized retaining wall block with a standardized shape is legal. Some types are stacked along the surface. The latter type of retaining wall is constructed from so-called precast concrete, in which the retaining wall block is manufactured in advance in a factory, so that it can be constructed inexpensively and easily.

Japanese Patent No. 3823075

  Patent Document 1 discloses a so-called box-type retaining wall block or a bottle-type retaining wall block. This retaining wall block has a substantially rectangular surface portion that appears on the surface side when the retaining wall is constructed, a substantially rectangular back surface portion that is approximately half the height of the surface portion, and a front surface portion and a back surface portion. And a pair of connecting portions that are connected to each other at a predetermined interval, and is configured to have a box shape with an open central portion. The necessary number of such retaining wall blocks are arranged in the lateral direction along the slope, and in the space part inside the retaining wall block and the space part between the retaining wall block and the slope, Filling with crushed stones, chestnuts, etc. and rolling, a first-stage retaining wall can be constructed. On the first stage retaining wall, shift the retaining wall blocks to the rear and arrange them in the horizontal direction so as to be adjacent to the slope, and for the interior space and retaining walls of these retaining wall blocks. Similarly, the space between the block and the slope is filled with crushed stones, chestnuts, and the like, and a second-stage retaining wall can be constructed by rolling. In the same manner, a multi-stage retaining wall can be constructed.

  In the retaining wall constructed by the retaining wall block described in Patent Document 1, since the back portion of the block is formed lower than the surface portion, the lower block and the upper block are not in direct contact with each other. The lower block and the upper block are stabilized by each other, and the shape of the retaining wall is maintained by intermingling crushed stones, chestnuts, and the like that are filling materials. Since the upper and lower blocks are not in direct contact with each other in this way, even if one block rotates, no rotational moment acts on the other block. Therefore, even if ground subsidence, sediment runoff, etc. occur, the deformation of the retaining wall is limited to a part of the steps and does not affect the whole, and a highly stable retaining wall can be constructed.

  If the retaining wall is constructed by the retaining wall block described in Patent Document 1, a relatively stable retaining wall can be obtained, and it can be said that this retaining wall block is excellent. However, there are some points to be improved. For example, there are problems with filling the filling material. The filling material is composed of crushed stones, chestnuts, etc. with relatively uniform particle diameters, so it can be expected that the frictional force and compressive force will act relatively evenly in all directions if they are uniformly filled. Can also be considered an isotropic material. However, since the particle diameters of crushed stones, chestnuts and the like are actually large and the shape is not uniform, depending on the shape of the portion to be filled, the filling state will be sparse and dense. If it does so, the part from which frictional force cannot fully be produced will arise, or the part which cannot fully respond to compression force will arise. In the retaining wall block described in Patent Document 1, since the opening is formed in a substantially rectangular shape, the filling material is densely filled in the central portion and the side of the square, but the filling is close in the vicinity of each apex angle. The degree tends to be sparse. As a result, the frictional force of the filling material in the vicinity of the apex angle does not work sufficiently, and the filling material tends to flow. Moreover, since the compressive force given from the filling material does not act equally on the opening, the balance of the force of the retaining wall block is lost.

  There are other points to improve. Strong earth pressure acts on the retaining wall block from the slope. The shape of the retaining wall is maintained against this earth pressure by the weight of the retaining wall blocks and the filling material stacked vertically. The earth pressure acts on the back portions of these retaining wall blocks, and the back portions are suppressed from the front by a pair of connecting portions. If it does so, a big force will act on a back part and a pair of connecting parts, and it will become easy to be destroyed in these parts. In the retaining wall block described in Patent Document 1, the shape of the back portion and the pair of connecting portions, in other words, the shape of the connecting portion of the back portion and the pair of connecting portions is not particularly considered, so a large earth pressure If it works, stress may concentrate and break.

  There are also points to be improved regarding work efficiency when building retaining walls. When filling and rolling with the filling material, filling and rolling must be carried out in a plurality of times. This is because the filling thickness must be about 30 cm in order for the filling material to be appropriately pressed. Therefore, when constructing the retaining wall for one stage, the retaining wall blocks are arranged side by side, filled with the filling material with a thickness of about 30 cm, and pressed, and further the filling material is placed on the compressed filling material. It is necessary to repeat filling and rolling of the filling material until the height of the retaining wall block is reached in the same manner. If it does so, work will become complicated and work efficiency will worsen. Furthermore, there is a problem that the connecting portion and the back portion provided in the retaining wall block deteriorate the working efficiency. That is, since the height of the connecting portion and the rear portion is generally higher than 30 cm, the connecting portion and the rear portion protrude above the upper surface of the filling material in the initial stage of filling the filling material. If it does so, these protrusion parts will become a hindrance to a compaction machine, and it cannot roll efficiently, and cost will be required for construction of a retaining wall.

  The present invention has been made in view of the above-described problems. Specifically, the filling material is uniformly filled, and thus the constructed retaining wall has high stability and a good balance of force. An object of the present invention is to provide a precast concrete retaining wall block having sufficient resistance against the earth pressure from the slope. Another object of the present invention is to provide a precast concrete retaining wall block with high work efficiency when constructing a retaining wall.

  In order to achieve the above object, the present invention configures a precast concrete retaining wall block as a so-called box-type retaining wall block or bin-shaped retaining wall block. This retaining wall block is composed of a surface portion that is exposed on the surface when the retaining wall is constructed, a back surface portion that is buried, and a pair of connecting portions that connect the surface portion and the back surface portion. The height is lower than the height of the surface portion. The central opening formed by the front surface portion, the back surface portion, and the pair of connecting portions and filled with the filling material is configured such that the upper surface has a substantially circular shape or a substantially elliptical shape. Further, when a plurality of retaining wall blocks are arranged in the horizontal direction, the upper surface of the space portion formed between two adjacent retaining wall blocks filled with the filling material is also substantially circular. Or it is comprised so that it may become a substantially elliptical shape. The height of the surface portion is 25 to 35 cm.

That is, in order to achieve the above-mentioned object, the invention according to claim 1 has a plurality of laterally abutted along the slopes such as cut and embankment and a predetermined number of steps stacked in the height direction. A retaining wall block that is filled with a filling material such as crushed stone or chestnut is constructed, and the retaining wall block is exposed to the surface side when the retaining wall is constructed. A pair of joints connecting the surface portion and the back surface portion, a substantially rectangular back surface portion that is lower in height than the surface portion and buried when a retaining wall is constructed. The central opening filled with the filling material, which is formed from the surface portion, the back surface portion, and the pair of connecting portions, has a substantially elliptical top surface shape. It is configured as a retaining wall block made of precast concrete.
The invention according to claim 2 is the retaining wall block according to claim 1, wherein when the plurality of retaining wall blocks are arranged in a horizontal direction, the retaining wall blocks are adjacent to each other. A space portion filled with the filling material is formed between the blocks, and the upper surface shape of the space portion is configured to have a substantially elliptical shape.
Invention of Claim 3 is a block for retaining walls of Claim 1 or 2, Comprising: The said back part is formed so that the height may be substantially 1/2 of the height of the said surface part. Consists of.
Invention of Claim 4 is a block for retaining walls as described in any one of Claims 1-3, Comprising: The height of the said front part is comprised so that it may be 25-35 cm.

  As described above, according to the present invention, a plurality of sheets are abutted in the lateral direction along the slopes such as cut and embankment, and a predetermined number of steps are stacked in the height direction. A retaining wall block that is filled with a filler so that a retaining wall is constructed, and the retaining wall block has a substantially rectangular surface portion that is exposed to the surface side when the retaining wall is constructed. Since it is composed of a substantially rectangular back surface that is buried when the retaining wall is built lower than the surface portion, and a pair of connecting portions that connect the surface portion and the back surface portion, so-called It can be referred to as a box-type retaining wall block or a bottle-type retaining wall block. Therefore, a stable retaining wall can be constructed using filling materials such as crushed stones and chestnuts. And since the height of a back surface part is lower than a surface part, when a retaining wall is constructed | assembled, the block for retaining walls of a lower stage and an upper stage does not contact | connect directly. Therefore, even if one block rotates, it does not affect the other, and even if ground subsidence, sediment runoff, etc. occur, the deformation of the retaining wall is limited to a part of the steps and does not affect the whole. And according to this invention, the upper surface shape is exhibiting the substantially ellipse shape of the center opening part filled with the filling material formed from a surface part, a back surface part, and a pair of connection part. Therefore, the following effects specific to the present invention can be obtained. That is, it can be ensured that the filling material is uniformly filled, and it can be expected that the friction force and compression force of the filling material act uniformly. The balance of power is also excellent. Furthermore, since the opening is formed in a substantially circular shape or a substantially elliptical shape and has a smooth shape, stress concentration can be prevented and high resistance to earth pressure is provided.

  According to another invention, when a plurality of retaining wall blocks are arranged in the lateral direction, a space portion filled with a filling material is formed between two adjacent retaining wall blocks. The upper surface shape of the part has a substantially circular shape or a substantially elliptical shape. That is, the filling material filled between two adjacent retaining wall blocks is also filled uniformly, and it can be ensured that the frictional force and the compressive force act uniformly. According to still another invention, since the height of the front surface portion is 25 to 35 cm, the overall height of the retaining wall block is also 25 to 35 cm. Then, when the retaining wall block is installed at the time of the construction of the retaining wall, when filling and rolling the filling material, the filling and the rolling pressure need only be performed once and do not need to be repeated. Then, work efficiency is high and a retaining wall can be constructed at low cost. In addition, since the back portion and the connecting portion are not exposed to the upper part during rolling of the filling material, there is no hindrance to the compacting machine, and an effect of efficiently rolling can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the block for retaining walls which concerns on embodiment of this invention, The (a), (b), (c) are the perspective view, the top view, and the side view of the block for retaining walls, respectively. It is a top view which shows the state which arranged two the blocks for retaining walls based on embodiment of this invention in the horizontal direction. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which illustrates typically the method of constructing a retaining wall with the retaining wall block which concerns on this Embodiment, The (a)-(e) is side sectional drawing of the retaining wall which shows each step in construction. is there.

  Embodiments of the present invention will be described below. A precast concrete retaining wall block 1 according to the present embodiment is a so-called box-shaped retaining wall block having a substantially box shape with an open top and bottom as shown in FIG. Alternatively, it is a type of retaining wall block called a bottle-type retaining wall block. The retaining wall block 1 is formed by joining a surface portion 2 having a predetermined thickness having a rectangular plate shape, a back surface portion 3 having a predetermined thickness similarly having a rectangular plate shape, and the surface portion 2 and the back surface portion 3. The pair of connecting portions 5 and 6 are integrally manufactured from concrete. Therefore, the front surface portion 2, the back surface portion 3, and the pair of connecting portions 5 and 6 form a box-like space whose upper and lower sides are opened inside, that is, the opening portion 7. When the retaining wall is constructed, the opening 7 is filled with a filling material such as crushed stone, chestnut stone, or slag.

  The retaining wall block 1 is formed such that the height h of the back surface portion 3 is lower than the height H of the surface portion 2, and when the retaining wall is constructed thereby, the retaining wall block 1 positioned above and below, 1 is arrange | positioned so that it may not mutually contact. Therefore, even if one retaining wall block 1 rotates, the other retaining wall block 1 is not affected. Any height can be used as long as the height h of the back surface portion 3 is lower than the height H of the surface portion 2, but in the present embodiment, the height h of the back surface portion 3 is the surface portion. 2 and approximately half the height H. As described above, since the height of the back surface portion 3 is lower than that of the surface portion 2, the pair of connecting portions 5 and 6 have a high portion connected to the surface portion 2 as shown in FIG. The part connected to the back part 3 is low. Further, the lateral width of the back surface portion 3 is formed slightly narrower than the lateral width of the surface portion 3. Since it is formed in this way, when arranging a plurality of retaining wall blocks 1, 1,... Laterally along the slope, even if the slope is curved forward, two adjacent blocks There is no gap between the surface portions 2 and 2 of the retaining wall blocks 1 and 1.

  The retaining wall block 1 according to the present embodiment is characterized by the shapes of the connecting portions 5 and 6, and the surface thereof is smoothly curved. As a result, the opening 7 has a substantially cylindrical shape, and the upper surface of the opening 7 has a substantially circular shape as shown in FIG. Further, since the outer surfaces of the connecting portions 5 and 6 are also curved, when the two retaining wall blocks 1 and 1 are arranged in the horizontal direction, as shown in FIG. 1, a space having a substantially circular top surface, that is, a substantially cylindrical space 9 is formed. The space portion 9 is also filled with the filling material.

  In the present invention, the size of the retaining wall block 1 is not particularly limited, and an appropriate size is selected according to the slope on which the retaining wall is constructed and various conditions such as the environment. However, if various conditions allow, it is preferable to construct the retaining wall using the retaining wall block 1 having a predetermined range of sizes. This is because if the size is within the predetermined range, the working efficiency of filling / rolling of the filling material performed at the time of construction as described below is high. In the present embodiment, the retaining wall block 1 is formed in the size of the predetermined range, and specifically, the height H of the surface portion 2 is selected to be 25 to 35 cm.

  A method for constructing a retaining wall by the retaining wall block 1 according to the embodiment of the present invention will be described. First, build one retaining wall. As shown in FIG. 3A, the retaining wall blocks 1a, 1a,... According to the present embodiment in which the ground contact surface G is leveled horizontally and the first stage is formed thereon are legal. They are arranged along the surface N in the horizontal direction, that is, in the direction perpendicular to the paper surface. At this time, the retaining wall blocks 1a, 1a,... , And the space portions 9, 9,... Formed between the openings 7, 7,... Of the retaining wall blocks 1 a, 1 a,. , And the filling material 12a is filled until the height is approximately equal to the surface portions 2, 2,... Of the retaining wall blocks 1a, 1a,. The thickness of the filled filling material is approximately 30 cm because it is substantially equal to the height of the surface portions 2, 2,... Of the retaining wall blocks 1a, 1a,. The filling material 12a is rolled by a predetermined rolling machine. Since the thickness of the rolling pressure is about 30 cm, the rolling can be performed appropriately. At the time of rolling, since the back surface part 3 and the connection parts 5 and 6 are not exposed, these do not disturb. FIG. 3 (a) shows a state in which the rolling is completed and the first stage retaining wall is constructed.

  As shown in FIG. 3C, on the first stage retaining wall, the retaining wall blocks 1b, 1b,... Forming the second stage are arranged in the horizontal direction along the slope N. . At this time, as in the case of the first stage construction, the back surface portions 3, 3,... Of the retaining wall blocks 1b, 1b,. Then, the retaining wall blocks 1b, 1b,... Constituting the second stage with respect to the retaining wall blocks 1a, 1a,. In the same manner as in the construction of the first stage, the filling material 12b is filled so that the height is substantially equal to the surface portion 2 of the retaining wall blocks 1b, 1b,. The inside filling material 12b is rolled. A second stage retaining wall is constructed. In the same manner, a multi-stage retaining wall is constructed. FIG. 3D shows a three-stage retaining wall.

  When the retaining wall is constructed from the retaining wall blocks 1, 1,... According to the present embodiment, the openings 7, 7,... And the space portions 9, 9,. The fillers 12a, 12b,... Are filled uniformly without being sparse. Therefore, the frictional force and compressive force act uniformly, and the stability of the retaining wall is high. Further, the connecting portions 5, 6,... Of the retaining wall blocks 1, 1,... Are smoothly connected to the back surface portion 3, and stress concentration is unlikely to occur, so that it is highly resistant to earth pressure from the slope N. It has. In the retaining wall to be constructed, the upper and lower retaining wall blocks 1, 1,... Are not in contact with each other, so that no rotational force is transmitted. Therefore, even if the filling material flows out, the ground sinks, etc., and the predetermined step of the retaining wall is deformed, the upper and lower steps are not affected.

  The retaining wall block 1 according to the present embodiment can be variously modified. For example, the opening 7 and the space 9 of the retaining wall block 1 have been described as having an upper surface formed in a substantially circular shape, but may be formed in a substantially elliptical shape. Even if it does in this way, the filling material can be filled uniformly and the tolerance with respect to earth pressure is also high. Further, various modifications can be made to the side shapes of the connecting portions 5 and 6. The connecting portions 5 and 6 are smoothly changed in height from a portion connected to the front surface portion 2 to a portion connected to the back surface portion 3, but are formed so as to change in height in a staircase shape. Also good. Not only the shape of the retaining wall block 1 but also the retaining wall construction method can be modified. In the present embodiment, it has been described that the retaining wall is constructed from the retaining wall blocks 1, 1,... And the filling material 12, but the retaining wall can be constructed by combining so-called geotextiles. When geotextile is used, it is possible to prevent the outflow of filling materials and earth and sand, and the effect of increasing the stability of the retaining wall can be obtained.

DESCRIPTION OF SYMBOLS 1 Block for retaining wall 2 Surface part 3 Back part 5 Connection part 6 Connection part 7 Opening part 9 Space part 12 Filling material

Claims (4)

A plurality of laterally abutted along the slopes of cut and embankment, etc. and a predetermined number of steps are stacked in the height direction, and inside these are filled with filling materials such as crushed stone and chestnut stone, and a retaining wall is built A retaining wall block adapted to be
The retaining wall block has a substantially rectangular surface portion exposed to the surface side when the retaining wall is constructed, and a substantially rectangular back surface portion that is lower than the surface portion and is buried when the retaining wall is constructed. And a pair of connecting portions connecting the front surface portion and the back surface portion,
The central opening formed by the front surface portion, the back surface portion, and the pair of connecting portions and filled with the filling material has a top surface that is substantially circular or elliptical. Retaining wall block made of precast concrete.   2. The retaining wall block according to claim 1, wherein a plurality of the retaining wall blocks are filled with a filling material between two adjacent retaining wall blocks when arranged in a horizontal direction. A retaining wall block made of precast concrete, wherein a space portion to be formed is formed, and an upper surface shape of the space portion is substantially circular or elliptical.   3. The retaining wall block according to claim 1, wherein the height of the back surface portion is approximately ½ of the height of the surface portion. 4. Retaining wall block.   The retaining wall block according to any one of claims 1 to 3, wherein the height of the front portion is 25 to 35 cm.

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