JP3022072U - L type concrete retaining wall block - Google Patents

Abstract

(57) [Summary] [Purpose] The excavation scale is reduced and vertical vertical installation is performed while forming the bottom plate that reduces the back ground pressure of the vertical wall of the L-type concrete retaining wall and increases the resistance to tipping and sliding. Provide possible lightweight retaining wall blocks. [Constitution] In the precast L-shaped concrete retaining wall block, at least a part of the lower surface of the bottom plate on the lower end side of the vertical wall is made horizontal at a right angle to the vertical wall, and its open end side is opened at an obtuse angle with the vertical wall. In addition to forming a sloping bottom plate with a sloping angle, a vertical reinforcing wall is provided in the vertical center of the vertical wall and the bottom plate on the side that receives earth pressure, and a hanging metal fitting mounting part is provided at appropriate points on the vertical wall and the vertical wall. A fitting for attaching the connecting metal and a drainage hole were formed. [Effect] By adding the reaction force of the bottom plate to the frictional force of the sliding surface to increase the sliding resistance, the vertical wall thickness is reduced, the size of the bottom plate is reduced, and the L-shaped concrete has high stability, structure, and construction reliability. To be able to construct a retaining wall.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a precast L-shaped concrete retaining wall block used to install a retaining wall for vertically mounting a vertical wall, and particularly to a retaining wall block characterized by stability, structure and terrain flexibility. Regarding

[0002]

[Prior art]

 Generally, the size of a conventional L-shaped retaining wall in which the bottom plate is formed at right angles to the vertical wall is determined by considering the earth pressure applied to the vertical wall, and the bottom plate is designed to satisfy its supporting force and stability conditions against falling and sliding. decide. However, since the allowable value for falling has a margin more than the allowable sliding condition, the bottom plate design is usually determined by considering the safety level against sliding. Here, FIG. 6 is a side sectional view showing an L-shaped retaining wall having a conventional structure in its installed state and showing one conventional example of a normal design.

That is, as shown in FIG. 6, the foundation ground A is excavated at an excavation scale hh ′ having a substantially parallel trapezoidal side cross-section indicated by a chain double-dashed line, and a vertical wall 1 and a vertical wall 1 are formed on the constructed foundation work 9. An L-shaped retaining wall composed of the bottom plate 2 is placed, and the back soil B is covered on the bottom plate 2. At this time, the penetration depth of the L-shaped retaining wall, that is, the penetration depth m of the vertical wall 1 is m ≧ 350 mm when the internal friction angle of the foundation ground is 30 ° or more, and m ≧ 450 mm when the internal friction angle is less than 30 °. Therefore, legal values are set for each. Therefore, the wall height Hf appearing on the ground surface of the foundation ground A is always shorter than the arm length Ha of the vertical wall 1, while the wall thickness of the vertical wall 1 depends on the earth pressure g applied to the arm length Ha. It is decided and sufficient thickness is secured. The bottom plate length L is determined by examining the fall resistance and sliding resistance F for each ground condition.

[0004]

[Problems to be solved by the device]

 However, the conventional solution for adding sliding resistance is a method that increases the ground contact area of the bottom plate 2 perpendicular to the vertical wall 1 and simply depends on the increase in frictional force, and reduces the retaining wall structure, weight or installation man-hours. However, there is no disclosure of technical contents related to other gains. The present invention relates to a precast molded product of an L-shaped concrete retaining wall block, which comprehensively solves problems including weight reduction of a vertical wall, increase of falling resistance and sliding resistance, and reduction of installation man-hours, and a curved line. The purpose is to form an L-shaped concrete retaining wall block that is flexible in construction and can be applied to terrain.

[0005]

[Means for Solving the Problems]

 The L-shaped concrete retaining wall block according to the present invention is at least a bottom plate of an L-shaped concrete retaining wall block obtained by precasting a vertical wall installed vertically and a bottom plate integrated at the lower end thereof. The lower surface of the vertical wall is slightly horizontal and has a horizontal shape at right angles to the vertical wall, and an inclined bottom plate is formed whose open end side is an obtuse angle with the vertical wall.

Further, according to the present invention, reinforcing ribs provided with hanging metal fitting mounting portions are integrally formed in the vertical direction of the central plane of the vertical wall rear wall portion and the bottom plate upper surface portion, and the reinforcing ribs are provided adjacent to the vertical wall sidewall portion. A fitting for mounting the L-shaped concrete retaining wall block is provided, and an appropriate number of drain holes are formed from the front wall to the rear wall of the vertical wall.

Further, the present invention is one in which a reinforcing bar is arranged so as to integrate the concrete molded body of the vertical wall and the inclined bottom plate.

[0008]

[Action]

 The inclined bottom plate formed by opening the vertical wall and the bottom plate at an obtuse angle reduces the required excavation amount by making the height of the vertical wall side rooting shallow during pre-installation excavation, and closes the lower end side of the vertical wall during construction. Place the horizontal part of the bottom surface of the inclined bottom plate on the load-receiving foundation concrete part to stabilize the open end of the inclined bottom plate and facilitate the vertical installation work of the vertical wall. After the soil covering, the inclined bottom plate receives the earth pressure from the foundation ground, and the bottom plate reaction force is generated in addition to the frictional resistance due to the slip between the bottom plate and the ground, and the horizontal component force is sufficient for the sliding resistance. In addition to the above, the lower end of the vertical wall that is closer to the above-ground part makes the wall height of the vertical wall, which was longer than the arm length that conventionally bears the soil pressure of the back soil, almost equal. Excessive earth pressure is not applied to the vertical wall reinforced by reinforcing bar reinforcement.

[0009]

【Example】

 An L-shaped concrete retaining wall block (hereinafter referred to as a retaining wall block) according to the present invention will be described below with reference to FIGS. 1 to 5. 1A and 1B are explanatory views of the configuration of the present invention. FIG. 1A is a side view showing a first embodiment, FIG. 1B is a side view showing a second embodiment, and FIG. 2 is a side sectional view showing the present invention, and FIG. 2 is a view for explaining the detailed structure of the present invention. (A) is a front view of the first embodiment, (B) is a front view of the second embodiment, and FIG. The structure of the reinforcing bar reinforcement of the L-shaped concrete retaining wall block of the present invention will be described. (A) is a front view of the reinforcement, (B) is a view of the AA arrow of (A), and FIG. 4 is The action characteristics occurring in the retaining wall constructed according to the present invention will be described. (A) is an earth pressure action diagram showing the distribution of generated earth pressure, (B) is a reaction force action diagram acting on the inclined bottom plate, FIG. 5 is a side cross-sectional view showing the depth of rooting, which also illustrates the effect produced on the retaining wall.

As shown in FIGS. 1 (A) and 2 (A), the retaining wall block 10 of the first embodiment of the present invention uses the vertical wall front wall portion 1a as a finishing surface, and excludes the lower side of the rear surface thereof. An edge wall 5 having an appropriate number of connecting metal fitting mounting portions 6 for connecting adjacent retaining wall blocks is formed on the outer peripheral three-circumferential portion. Then, the bottom plate is continuously provided to the lower end portion 1d of the vertical wall and overhangs to form an inclined bottom plate 3 which forms an obtuse angle with the vertical wall 1. The bottom surface of the inclined bottom plate 3 is a bottom horizontal portion 3b in which the width on the lower end 1d side of the vertical wall is made horizontal at a right angle to the vertical wall 1, and then the vertical wall 1 and α ° (= 90 ° + about 15 °) The bottom inclined portion 3c is formed at an angle of. Further, the inclined bottom plate 3 has a trapezoidal plane projection surface. In addition, a reinforcing rib 4 having an appropriate number of hanging metal fitting mounting portions 7 is formed so as to extend vertically between the bottom plate upper surface portion 3a and the substantially central portion of the back surface of the vertical wall 1. It should be noted that 8, 8'provided in the vertical wall 1c, 1c 'penetrating the front and rear of the vertical wall 1 are drain holes.

As shown in FIGS. 1 (B) and 2 (B), the retaining wall block 10 according to the second embodiment of the present invention is a simple type in which the edge wall 5 is not provided on the side wall portion of the vertical wall 1. The bottom plate inclined side wall 3d is formed from an appropriate position of the inclined bottom plate 3 toward the open end. The other parts have the same structure as in the first embodiment. In both the first and second embodiments, the connecting metal fitting mounting portion 6 is constructed so that it can be fastened with bolts and nuts, and the hanging metal fitting mounting portion 7 is a through hole through which a hanging bolt can be inserted. Further, the drainage hole 8 is arbitrarily provided in the central portion or the side wall of the vertical wall 1.

As shown in FIG. 3, inside the retaining wall block 10 according to the embodiment of the present invention, the reinforcing bars 11 are entirely arranged and integrated to form a reinforced concrete reinforcing bar. There is. Reinforcing bar 11 is connected and fixed by adding a sub-bar to the main bar.

The retaining wall block 10 configured as described above is constructed as shown in FIG. 1 (C). First, it is measured upward from the open end bottom surface of the inclined bottom plate 3 of the retaining wall block 10 to satisfy the legal value of the rooting height, and at a position where the burial allowance of the vertical wall 1 is appropriately obtained. Set the level. According to the setting, the foundation ground A is excavated at the scale of the lateral cross section h-h 'indicated by the chain double-dashed line, and foundation stones are laid corresponding to the size of the inclined bottom plate 3 of the retaining wall block 10. A basic concrete 9a for load receiving with a concrete strength of at least 180 kg / cm2 is placed on the basic cobblestone at a position where the entire horizontal surface 3b of the bottom having a slight width with the lower end 1d of the vertical wall as a base point can be placed. And the blanking concrete 9b are placed in the other portions, respectively, to complete the foundation work 9. Retaining wall blocks 10 are continuously arranged on the completed foundation work 9 and are connected and fixed. Finally, the back soil B is covered on the vertical wall rear wall portion 1b side of the retaining wall block 10 and on the inclined bottom plate 3. Here, when the burying margin m1 of the vertical wall 1 up to the bottom plate horizontal portion 3b of the vertical wall 1 is set in the foundation ground A, the wall height Hf is equal to the arm length Ha. In addition, c indicated by a three-dot chain line is a sliding surface on which the frictional force of the inclined bottom plate 3 acts on the foundation ground A.

Next, referring to FIG. 4, the retaining wall structure relating to the earth pressure applied to the retaining wall block 10 of the present invention and the earth pressure will be described. As shown in FIG. 4 (A), the earth pressure g applied to the vertical wall 1 by the back soil B is applied to the arm length. In this case, however, when the arm length is almost equal to the wall height Hf. The wall thickness of the vertical wall 1 of the retaining wall block 10 can be designed to be the minimum dimension because the arm length cannot be further minimized. The earth pressure d due to the top load and the earth pressure e due to the back soil are applied to the whole from the lowermost end of the inclined bottom plate 3 to the upper end of the vertical wall 1, and as a countermeasure against both earth pressures d and e, first. It is examined that the earth pressure Fs applied to the sliding surface c acts as a sliding resistance force F generated in the direction of the arrow shown in the figure. Next, as shown in FIG. 4 (B), the earth pressure Fr applied to the inclined bottom plate 3 The horizontal component force fH of the bottom plate reaction force f generated at the bottom plate action point is calculated and added, and the safety level of 1.5 is added to the total sliding resistance obtained to determine the bottom plate length L.

Next, FIG. 5 shows one specific example. The retaining wall block width L is determined by the bottom plate inclination angle α at which the vertical wall 1 and the inclined bottom plate 3 open at an obtuse angle on the back soil B side, and as a result, the actual height of the vertical wall 1 is the upper end of the vertical wall 1. The dimension m2 can be made lower than the height of the retaining wall block which is determined by the open end of the inclined bottom plate 3. Therefore, in the above-ground part on the front side of the vertical wall 1, when the rooting height in the foundation ground A is set as the reference value m ≧ 350 mm, the burial depth of the vertical wall 1 is m1 obtained by subtracting the dimension m2 from the reference value. The vertical wall 1 can be buried shallowly. For example, when the dimension m2 is 200 mm, and the legally set height is m = 350 mm, the burying margin of the vertical wall 1 is m1 = 350-200 = 150 mm, and the inclined bottom plate 3 is concrete molded. The value is almost equal to the thickness of 120 mm.

Since a plurality of prefabricated retaining wall block products produced at the factory are to be installed and transported to the site, the inclined bottom plate 3 is formed within the dimension m2 provided when the inclined bottom plate 3 is formed when loading on the carrier of the carrier. Since they can be sequentially stacked, a far larger number of products can be loaded as compared with the conventional product opened at a right angle.

[0017]

[Effect of device]

 According to the present invention, by forming the inclined bottom plate, the horizontal component force, that is, the bottom plate reaction force, which is a resistance element different from the friction force in the same direction as the friction force generated on the sliding surface, is positively drawn out. As a result, the total sliding resistance and falling resistance could be increased without easily increasing the bottom plate area unlike the conventional complete L-shaped retaining wall, and the earth pressure by the back soil that determines the vertical wall thickness The total weight of the retaining wall block precast molded products has been reduced. In addition, it is excellent in stability and structure, the excavation scale is reduced, the stable installation is easy, the weight is reduced, and the shape of the retaining wall block makes it more efficient to carry in and transport and the cost is reduced. The effect of concrete retaining wall block is extremely large.

[Brief description of drawings]

FIG. 1 is a side view showing the structure of an L-shaped concrete retaining wall block according to the present invention, FIG.
(B) is a side view showing the second embodiment, and (C) is a side sectional view showing the installation and construction state of the embodiment.

FIG. 2 is a view for explaining the detailed structure of the L-shaped concrete retaining wall block of the present invention, (A) is a front view of the first embodiment,
(B) is a front view of the second embodiment.

FIG. 3 is a view for explaining the detailed structure of the reinforcing bar reinforcement of the L-shaped concrete retaining wall block of the present invention, (A) is a front view of the reinforcement bar,
(B) is a view on arrow AA of (A).

FIG. 4 is a diagram for explaining the action characteristics that occur in the retaining wall constructed according to the present invention. (A) is an earth pressure action diagram showing the distribution of generated earth pressure, and (B) is a reaction force action acting on the inclined bottom plate. is there.

FIG. 5 is a side sectional view showing a rooting depth for explaining the effect of the retaining wall constructed according to the present invention.

FIG. 6 is a side cross-sectional view showing an L-shaped retaining wall having a conventional structure in its construction state and showing one conventional example of a normal design.

[Explanation of symbols] 1 vertical wall, arm 1a vertical wall front wall portion 1b vertical wall rear wall portion 1c vertical wall side wall portion 1d vertical wall lower end portion 2 bottom plate 3 inclined bottom plate 3a bottom plate upper surface portion 3b bottom surface horizontal portion 3c bottom surface inclination Part 3d Bottom plate inclined side wall 4 Reinforcement rib 5 Edge wall 6, 6'Connecting metal fitting mounting part 7 Hanging metal fitting mounting part 8 Draining 9 Basic work 9a Load receiving basic concrete 9b Drying concrete 10 Retaining wall block 11 Reinforcing bar A Foundation soil B Back soil c Sliding surface d Earth pressure due to top load e Earth pressure due to back soil f Reaction force generated at bottom plate action point fH Horizontal component force of reaction force generated at bottom plate action point Fr Earth pressure on bottom plate F Sliding resistance force Fs Earth pressure on sliding surface Hf Wall height Ha Arm length h, h ′ Excavation scale g Earth pressure on arm length m, m1, m2 Rooting height L Ground slip length, retaining wall block width α Bottom plate tilt angle

Claims (3)

[Scope of utility model registration request] 1. An L-shaped concrete retaining wall block in which a vertical wall (1) installed in a vertical direction and a bottom plate integrated with a lower end portion of the vertical wall are precast, and at least a lower end portion of the vertical wall (underside of the bottom plate) 1d) side is slightly wide and is horizontal at right angles to the vertical wall (1), and the open end side is an inclined bottom plate (3) in which the vertical wall (1) and the inclined wall that forms an obtuse angle are formed. -Retaining wall block. 2. A vertical wall rear wall portion (1b) and a bottom plate upper surface portion (3).
Reinforcing ribs (4) provided with hanging metal fitting mounting portions (7) are integrally formed in the vertical direction of the central portion of the plane of a), and a retaining wall block adjacent to the vertical wall side wall portion (1c) is fastened. The connection fitting mounting portion (6) is provided, and an appropriate number of drainage holes (8) penetrating from the front wall portion (1a) to the rear wall portion (1b) of the vertical wall (1) is formed. L-shaped concrete retaining wall block. 3. The L-shaped concrete retaining wall block according to claim 1, further comprising a reinforcing bar (11) for integrating the concrete molded body of the vertical wall (1) and the inclined bottom plate (3).