Retaining wall block, and retaining wall

Abstract

To provide a retaining wall block which has an excellent function of draining water in the ground of a back side of a retaining wall and prevents foreign matter from flowing in, and a retaining wall equipped with such a retaining wall block.SOLUTION: A retaining wall blocks 1 to be stacked to form a retaining wall comprises a drainage groove 18 that extends vertically and is arranged from a top to a bottom of a back side of the retaining wall block 1. The drainage groove 18 comprises an opening 19 that opens on a back side 11 of the retaining wall block 1 with a width smaller than the dimensions of a foreign object 25 to be prevented from flowing in and that is arranged from the top to the bottom of the back side of the retaining wall block 1.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to blocks for retaining walls that are used to form retaining walls by stacking them and then filling the interior with cast-in-place concrete. [Background technology]

[0002] Retaining walls require some method of draining water from the ground behind them. A widely used drainage method involves placing pebbles behind the wall and providing drainage holes that penetrate the wall from the back to the front, allowing water to be drained to the front of the wall (see, for example, Figure 1 of Patent Document 1).

[0003] Furthermore, Patent Document 2 describes a masonry block that includes a front wall, a rear wall provided on the back side of the front wall, and an intermediate section interposed between the front and rear walls. In this masonry block, a drainage cutout is formed by the front wall, rear wall, and intermediate section, and a drainage hole is drilled in the rear wall, penetrating from the back side of the rear wall to the drainage cutout. Water in the ground flows through the drainage hole into the drainage channel formed by the drainage cutout, and is drained from the bottom end of the retaining wall (Figure 1 of Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-197534 [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-64706 Summary of the Invention [Problem to be solved by the invention]

[0005] The method of draining water through drainage holes has the problem that even if pebbles are used, dirt and debris mixed in the soil easily enters the drainage holes. Also, the cross-sectional area of ​​the drainage holes is small compared to the area of ​​the back of the retaining wall, which means that sufficient drainage cannot be achieved.

[0006] The method of constructing drainage channels by using cutouts in masonry blocks described in Patent Document 2 had the problem that it was difficult to apply to blocks in which cast-in-place concrete is filled inside the blocks.

[0007] Therefore, the present invention aims to provide retaining wall blocks that have excellent functionality in draining water from the ground behind the retaining wall and are less likely to allow foreign matter to flow in, and a retaining wall equipped with such retaining wall blocks. [Means for solving the problem]

[0008] The retaining wall block of the present invention is characterized in that it has a drainage groove extending in the vertical direction and arranged from the upper end to the lower end on the back side of the retaining wall block, and this drainage groove opens on the back side of the retaining wall block with a width smaller than the dimensions of the foreign objects to be prevented from flowing in, and has an opening arranged from the upper end to the lower end on the back side of the retaining wall block. [Effects of the Invention]

[0009] The retaining wall block of the present invention is provided with a drainage ditch extending vertically and arranged from the upper end to the lower end on the back side of the retaining wall block. The drainage ditch has an opening that opens on the back side of the retaining wall block and is arranged from the upper end to the lower end on the back side of the retaining wall block. This increases the area of ​​the opening that allows water from the back ground to flow in, thereby providing excellent drainage functionality. The width of the opening is smaller than the dimensions of foreign objects that should be prevented from flowing in, so the inflow of foreign objects can be effectively prevented.

[0010] The retaining wall of the present invention is provided with the above-described retaining wall blocks, and therefore can exhibit excellent drainage function and can effectively prevent the inflow of foreign matter. [Brief explanation of the drawings]

[0011] [Figure 1]FIG. 1(a) is a plan view of a retaining wall block according to one embodiment of the present invention, FIG. 1(b) is a front view thereof, and FIG. 1(c) is a rear view thereof. [Figure 2] FIG. 2(a) is a side view of a retaining wall block according to one embodiment of the present invention, and FIG. 2(b) is a cross-sectional view of the same. [Figure 3] 3(a), 3(b), 3(c), and 3(d) are diagrams showing examples of cross-sectional shapes of drainage grooves. [Figure 4] FIG. 4(a) is a front view of a retaining wall block with drainage holes according to one embodiment of the present invention, and FIG. 4(b) is a cross-sectional view of the same. [Figure 5] FIG. 5(a) is a side view of a retaining wall according to one embodiment of the present invention, and FIG. 5(b) is a diagram illustrating the flow of water in the retaining wall. [Figure 6] FIG. 6(a) is a front view of a retaining wall according to one embodiment of the present invention, and FIG. 6(b) is a partial rear view of the same. [Figure 7] FIG. 7(a) is a rear view of the retaining wall block according to the first embodiment of the present invention, FIG. 7(b) is a side view of the same, and FIG. 7(c) shows the cross-sectional shape of the drainage groove. [Figure 8] FIG. 8(a) is a rear view of a retaining wall block according to a second embodiment of the present invention, and FIG. 8(b) is a side view of the same. [Figure 9] FIG. 9(a) is a rear view of a retaining wall block according to a third embodiment of the present invention, and FIG. 9(b) is a side view of the same. DETAILED DESCRIPTION OF THE INVENTION

[0012] A retaining wall block 1 according to one embodiment of the present invention will be described below. Figure 1(a) is a plan view of the retaining wall block 1, Figure 1(b) is a front view thereof, Figure 1(c) is a rear view thereof, Figure 2(a) is a side view thereof, and Figure 2(b) is a cross-sectional view thereof (taken along line AA in Figure 1(a)).

[0013] The outer shape of the retaining wall block 1 is a roughly rectangular parallelepiped, and a concrete filling groove 16 is provided on each of the top surface 14 and bottom surface 15. The concrete filling groove 16 is provided in the center of the thickness direction of the retaining wall block 1 (the vertical direction in Figure 1(a)), extending from the left side surface 12 to the right side surface 13. The cross-sectional shape of the concrete filling groove 16 is a trapezoid whose width gradually narrows from the top surface 14 or bottom surface 15 toward the center.

[0014] The material of the retaining wall blocks 1 is mainly assumed to be cement concrete, but other materials such as natural stone can also be used as long as the stability and strength of the retaining wall can be ensured.

[0015] The retaining wall block 1 is provided with one concrete filling hole 17a and two concrete filling holes 17b. Both concrete filling holes 17a and 17b penetrate from the top surface 14 to the bottom surface 15. The cross-sectional shape of the concrete filling hole 17a is a square with the length of each side being approximately 1 / 3 of the thickness of the retaining wall block 1. In plan view, the concrete filling hole 17a is located at the center in the thickness direction and the left-right direction (left-right direction in Figure 1(a)). The cross-sectional shape of the concrete filling hole 17b is a rectangle with a width dimension that is 1 / 2 the width dimension of the concrete filling hole 17a and a thickness dimension that is the same as the thickness dimension of the concrete filling hole 17a. In plan view, the concrete filling holes 17b are located at the center in the thickness direction and at both ends in the left-right direction. When the retaining wall blocks 1 are stacked, the concrete filling hole 17b becomes one with the concrete filling holes 17b of the adjacent retaining wall blocks 1 on the left and right, forming a concrete filling hole whose cross-sectional shape is the same square as the concrete filling hole 17a.

[0016] By arranging the concrete filling groove 16 and concrete filling holes 17a, 17b in this manner, a lattice-like space can be formed inside the retaining wall blocks 1 when they are stacked, and by filling this space with concrete, a large number of retaining wall blocks 1 can be integrated to form a retaining wall.

[0017] The above-mentioned shape and arrangement of the concrete filling groove 16 and concrete filling holes 17a, 17b are examples, and a different configuration may be used as long as a communicating space is formed inside the retaining wall and concrete can be filled therein.

[0018] The front surface 10 of the retaining wall block 1 is chamfered 21 by about 10 mm around the four edges.

[0019] Three drainage ditches 18 are provided on the back surface 11 of the retaining wall block 1, extending vertically from the upper surface 14 to the lower surface 15. The drainage ditches 18 have openings 19 on the back surface 11 that extend vertically (vertical direction in Figure 1(b)) from the upper surface 14 to the lower surface 15. The openings 19 are also arranged from the upper surface 14 to the lower surface 15 of the retaining wall block 1. The drainage ditches 18 are arranged in a plan view, with one at the center and one at each end in the left-right direction of the retaining wall block 1. The left-right spacing of the drainage ditches 18 is preferably 300 mm or less.

[0020] Because the drainage ditches 18 are arranged in this manner, whether the retaining wall blocks 1 adjacent to each other are stacked so that their left and right side surfaces 12, 13 are aligned, or whether they are stacked so that they are offset by 1 / 2 the width of the retaining wall blocks 1 (see Figure 6(b)), the left and right positions of each drainage ditch 18 will be aligned between the upper and lower retaining wall blocks, and a continuous drainage channel can be formed from the top to the bottom of the retaining wall.

[0021] Therefore, the retaining wall block 1 has a large area of ​​the opening 19 through which water in the back ground 34 (see FIG. 6(a)) flows in, and can exhibit excellent drainage function.

[0022] 3(a), (b), (c), and (d) show examples of the cross-sectional shape of the drain groove 18. In either example, the width w1 of the opening 19 is set to be smaller than the size D of the foreign object 25 that needs to be prevented from flowing into the drainage ditch 18, and to allow water in the ground behind the retaining wall to flow smoothly into the drainage ditch 18. In this way, it is possible to prevent foreign objects from flowing into the drainage ditch 18. Here, the size of the foreign object 25 refers to the size of the smallest sieve opening that the foreign object 25 can pass through, similar to how the maximum size of coarse aggregate in concrete is expressed.

[0023] In addition, in all examples, the drainage ditch 18 located at the left and right ends of the retaining wall block 1 is formed by dividing the shape shown in each figure into two symmetrical parts, and is combined with the drainage ditch 18 located at the end of the adjacent retaining wall block 1 to form the drainage ditch 18 of the shape shown in each figure.

[0024] The shape shown in Figure 3(a) is the shape that the inventors consider most suitable. The cross-sectional shape of the drainage ditch 18 is a trapezoid whose width gradually increases from the back surface 11 side to the front surface 10 side. For example, if small particles contained in the crushed stone in the backfill are assumed to be foreign matter, it is preferable that the width w1 of the opening 19 is about 10 mm. It is preferable that the width w2 and depth d of the front end be of similar dimensions.

[0025] By making the cross-sectional shape of the drain groove 18 as shown in Figure 3(a), the thickness of the vicinity 20 of the opening 19 becomes thicker, making it less likely to chip. Also, the cross-sectional area required to drain water can be secured without increasing the depth d.

[0026] Figure 3(b) shows an example in which the cross-sectional shape of the drainage ditch 18 is a circular shape with a portion cut out so that the width of the opening 19 is w1. In this way, a pre-fabricated circular pipe member can be used as a formwork for forming the drainage ditch 18, improving workability. However, if the cross-sectional area of ​​the drainage ditch 18 and the width w1 of the opening are made similar to those in the example of Figure 3(a), there is a drawback in that the thickness of the vicinity 20 of the opening 19 becomes small and is prone to chipping.

[0027] Figure 3(c) shows an example in which the cross-sectional shape of the drainage ditch 18 is a rectangle with a constant width. This provides the best workability and is less likely to chip around the opening 19. However, if the cross-sectional area of ​​the drainage ditch 18 and the width w1 of the opening are the same as in the example of Figure 3(a), the depth d will be much larger than the width w1, resulting in a long, narrow shape that is prone to clogging with soil and other materials that inevitably flow in to some extent. If the depth d of the drainage ditch 18 and the width w1 of the opening are the same as in the example of Figure 3(a), it will not be possible to ensure a sufficient cross-sectional area for water to flow through.

[0028] Figure 3(d) shows an example in which the width changes in a stepped manner from the width w1 of the opening to the width w2 on the front side. If the cross-sectional area of ​​the drainage groove 18 and the width w1 of the opening are kept the same as in Figure 3(a), the depth d can be made smaller than in the example of Figure 3(c), but this has the disadvantages of being more complicated to install and of being somewhat prone to chipping in the vicinity 20 of the opening 19.

[0029] Next, a description will be given of the retaining wall block with drainage holes 2. The retaining wall block with drainage holes 2 has the same configuration as the retaining wall block 1 described above, except that it is provided with drainage holes 22. FIG. 4(a) is a front view of the retaining wall block 2 with drainage holes, and FIG. 4(b) is a cross-sectional view (BB in FIG. 4(a)) of the same. The two drainage holes 22 are provided near the center of the retaining wall block 2 with drainage holes when viewed from the front, penetrating from the front surface 10 to the back surface 11. The cross-sectional shape of the drainage holes 22 is a vertically long rectangle with a height approximately twice its width. The height of the drainage holes 22 is approximately one-third of the overall height of the retaining wall block 2 with drainage holes. The space between the two drainage holes 22 is approximately the same as the width of the drainage holes 22.

[0030] Next, an outline of the structure and construction method of the retaining wall 3 constructed using the retaining wall block 1 and the retaining wall block with drainage holes 2 will be described. Figure 5(a) is a side view of the retaining wall 3, Figure 5(b) is a diagram explaining how water flows in the retaining wall 3, Figure 6(a) is a front view of the retaining wall 3, and Figure 6(b) is a partial rear view of the retaining wall 3.

[0031] In this embodiment, the retaining wall 3 is inclined so that it leans toward the rear side, but an upright retaining wall can also be formed using retaining wall blocks 1 and retaining wall blocks 2 with drainage holes.

[0032] A leveling concrete 32 for adjusting the gradient is poured on top of a previously constructed foundation 31. The top surface of the leveling concrete 32 is adjusted to match the gradient of the retaining wall 3. In addition, backfill material 36 such as pebbles or crushed stone is placed between the back surface of the retaining wall 3 and the rear-side ground 34.

[0033] A predetermined number of the first tier of retaining wall blocks 1 and retaining wall blocks with drainage holes 2 are lined up in close contact with each other in the left-right direction on top of the leveled concrete 32. The second tier of retaining wall blocks 1 are stacked so that they are offset left-right by half the width of the retaining wall blocks 1 relative to the first tier of retaining wall blocks 1 and retaining wall blocks with drainage holes 2 (in a so-called staggered pattern). Retaining wall blocks 1 are stacked in the same way from the third tier onwards to the required height.

[0034] In the space 37 formed by the concrete filling groove 16 and the concrete filling holes 17a, 17b, reinforcing bars are placed vertically and / or horizontally as required.

[0035] Next, ready-mixed concrete is poured through the concrete filling holes 17a, 17b to integrate the stacked retaining wall blocks 1 and the retaining wall blocks with drainage holes 2 to form the retaining wall 3. The placement of horizontal reinforcing bars and the filling of ready-mixed concrete may be done after all the layers have been stacked, or may be done for each layer or for several layers at a time.

[0036] If necessary, top concrete 33 is poured to form the top of the retaining wall 3 horizontally.

[0037] In this example, the retaining wall blocks 2 with drainage holes are placed every three blocks only on the first tier (bottom tier), but the placement interval can be determined as appropriate depending on the soil quality of the back ground 34 and the amount of rainfall. They may also be placed not only on the bottom tier but also on intermediate tiers as appropriate. For example, if the ground level of the front ground 35 is about halfway between the retaining wall blocks 1 in the second tier from the bottom, the blocks 2 with drainage holes are placed in the third tier from the bottom. Alternatively, the retaining wall 3 may be formed using only the retaining wall blocks 1, without using the retaining wall blocks 2 with drainage holes.

[0038] Water that flows into the drainage ditch 18 flows down inside the drainage ditch 18 as shown by arrow a in Figure 5(b) and reaches the lower end of the retaining wall 3. At the lower end of the retaining wall 3, the water is guided and discharged to a gutter or culvert in an appropriate manner. Furthermore, water that cannot be collected by the drainage ditch 18 and remains in the rear ground 34 is discharged to the front of the retaining wall 3 through the drainage holes 22 as shown by arrow b in Figure 5(b). In order for the water to flow in this way, the shape of the drainage holes 22 is adjusted so that the front side lower end 23 of the drainage hole 22 is lower than the rear side upper end 24 of the drainage hole 22 when the retaining wall blocks 2 are installed.

[0039] When vertically adjacent retaining wall blocks 1, 2 are arranged with a lateral offset, as in this example, the positions and spacing of the openings 19 are adjusted so that the left-right positions of the openings 19 of the upper and lower retaining wall blocks 1 match, as shown in Figure 6(b). For example, when stacking in a staggered pattern, the openings 19 should be positioned at least at both ends and in the center in the left-right direction, and the openings 19 should be spaced equally apart. The same applies to the concrete filling holes 17a, 17b. [Example]

[0040] Next, we will explain the retaining wall block 4, which is a first embodiment of the present invention. Fig. 7(a) is a rear view of the retaining wall block 4, Fig. 7(b) is a side view of the same, and Fig. 7(c) is a diagram showing the cross-sectional shape of the drainage groove 18. The dimensions in the figures are in millimeters. The basic structure of the retaining wall block 4 is the same as that of the retaining wall block 1.

[0041] The external dimensions of the retaining wall block 4 are 600 mm wide, 300 mm high, and 300 mm thick. Three drainage channels 18 are provided, one at the center and one at each end of the back surface 11. The cross-sectional shape of the drainage channels 18 is a trapezoid with an opening 19 width of 10 mm, a width of 40 mm on the front side, and a depth of 30 mm.

[0042] The top and bottom surfaces are each provided with a concrete filling groove 16. The opening width of the concrete filling groove 16 is 100 mm, the width at the bottom is 50 mm, and the depth is 100 mm. [Example]

[0043] Next, a retaining wall block 5 according to a second embodiment of the present invention will be described. Fig. 8(a) is a rear view of the retaining wall block 5, and Fig. 8(b) is a side view of the same. The dimensions in the figures are in millimeters. The basic structure of the retaining wall block 5 is the same as that of the retaining wall block 1.

[0044] The external dimensions of the retaining wall block 5 are 1000 mm wide, 500 mm high, and 500 mm thick. A total of five drainage grooves 18 are arranged at 250 mm intervals on the back surface 11, one on each end and three in the middle. The cross-sectional shape of the drainage grooves 18 is the same as in the first embodiment.

[0045] The top and bottom surfaces are each provided with a concrete filling groove 16. The opening width of the concrete filling groove 16 is 200 mm, the width at the bottom is 100 mm, and the depth is 150 mm. [Example]

[0046] Next, a retaining wall block 6 according to a third embodiment of the present invention will be described. Fig. 9(a) is a rear view of the retaining wall block 6, and Fig. 8(b) is a side view of the same. The dimensions in the figures are in millimeters. The basic structure of the retaining wall block 6 is the same as that of the retaining wall block 1.

[0047] The external dimensions of the retaining wall block 6 are 2000 mm wide, 1000 mm high, and 500 mm thick. A total of 11 drainage grooves 18 are arranged at 200 mm intervals on the back surface 11, one on each end and nine in the middle. The cross-sectional shape of the drainage grooves 18 is the same as in the first embodiment.

[0048] The top and bottom surfaces are each provided with a concrete filling groove 16. The opening width of the concrete filling groove 16 is 200 mm, the width at the bottom is 100 mm, and the depth is 200 mm. [Explanation of symbols]

[0049] 1 Retaining wall blocks 1, 4, 5, 6 2 Retaining wall blocks with drainage holes 10 Front 11 Back 12 Left side 13 Right side 14 Top side 15 Bottom side 16 Concrete-filled trench 17a, 17b Concrete filling holes 18 Drain 19 Opening 20 neighborhoods 21 Chamfering 22 Drain hole 23 Lower front edge of drain hole 24 Top rear edge of drain hole 25 Foreign object 3. Retaining walls 31 Basics 32 Leveling concrete 33 Top Concrete 34 Rear side ground 35 Front side ground 36 Backfill material 37 Space

Claims

1. In a retaining wall block used to form a retaining wall by stacking, A drainage groove is provided which extends in the vertical direction and is arranged from the upper end to the lower end on the back side of the retaining wall block, A retaining wall block characterized in that the drainage ditch opens on the back of the retaining wall block with a width smaller than the dimensions of the foreign objects to be prevented from flowing in, and has an opening arranged from the upper end to the lower end on the back side of the retaining wall block.

2. 2. The retaining wall block according to claim 1, wherein the cross-sectional shape of the drainage ditch is a trapezoid whose width on the front side is greater than the width of the opening.

3. The external shape is approximately rectangular parallelepiped, a concrete filling groove provided on the upper and lower surfaces of the retaining wall block from one end to the other in the left-right direction; A retaining wall block according to claim 1 or claim 2, characterized in that it is provided with concrete filling holes at least at the center and both ends in the left-right direction, penetrating from the top surface to the bottom surface of the retaining wall block.

4. The retaining wall block has a pair of drainage holes that penetrate from the front to the back and are located near the center in the left-right direction.

3. The retaining wall block according to claim 1, wherein the distance between the pair of drainage holes in the left-right direction is approximately equal to the width of the drainage holes.

5. A retaining wall formed from the retaining wall blocks according to claim 1 or 2.

6. A retaining wall formed from the retaining wall blocks according to claim 3.

7. A retaining wall formed from the blocks for retaining walls according to claim 1 and the blocks for retaining walls according to claim 4.

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