JP4026675B2 - Support structure for avalanche and rock fall protection body - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a support structure for avalanche / falling rock protection fences in an avalanche / falling rock protection fence, a protection net, a protective wall and the like.
[0002]
[Problems to be solved by the invention]
Conventionally, as this type, a plurality of support columns are set up on a concrete foundation at equal intervals, a net is stretched between the support columns, and guard rope ends are attached to the support columns at both ends of the plurality of support columns. There is an avalanche / falling rock protection fence that has been established and stretched, and as is known in Japanese Utility Model Publication No. 56-77516, etc., it is made of H-shaped steel on a concrete foundation cast at the bottom of the slope. A large number of high pillars and low pillars are erected (publication microfilm, page 4), and the lower parts of these pillars are embedded in the concrete foundation (publication FIG. 3).
[0003]
FIG. 10 is a cross-sectional view in which the lower part of the support column 102 is fixed to the concrete foundation 101. When a guard fence having such a support column 102 receives a falling rock, the falling rock energy is absorbed by the deformation of the support column 102. To replace the post 102, the concrete base 101 must be suspended, the post 102 must be removed, and the lower part of the new post 102 must be fixed to the base 101 with concrete. There is a problem that labor is required.
[0004]
Further, as shown in FIG. 10, when a force for bending the support column 101 is applied by the falling rock from the front S side indicated by the arrow R, the lower portion of the support column 101 is restrained by the concrete foundation 101, so Since local stress is generated in the back portion 102H of the constrained support column 102 and the back surface portion 102H is locally buckled before the entire circumference of the support column 102 is deformed, there is a surface inferior in energy absorption efficiency.
[0005]
Accordingly, the present invention aims to provide a support structure for an avalanche / falling rock protector that allows easy replacement of the support, and also supports the avalanche / falling rock protector that has excellent energy absorption efficiency due to deformation of the support. The purpose is to provide a structure.
[0006]
[Means for Solving the Problems]
According to the first aspect of the present invention, in the support structure for an avalanche / falling rock protection body in which the support is attached to a concrete foundation, the lower part of the support is attached to the support hole for the support of the foundation, and the upper part of the attachment hole is at least The back side of the column is enlarged and formed upward.
[0007]
According to the first aspect of the present invention, when the support column is bent, the upper portion of the mounting hole is enlarged upward, so that the energy absorption efficiency due to deformation does not occur without causing local buckling of the support column. Will improve.
[0008]
According to a second aspect of the present invention, in the support structure for an avalanche / falling rock protector for attaching a support to a concrete foundation, a cylinder harder than the foundation is provided in the support hole for the support of the foundation, and the support is attached to the cylinder. The upper part of the cylindrical body is formed such that at least the back side of the column is enlarged upward.
[0009]
According to the second aspect of the present invention, when the support column is bent and deformed, the lower portion of the support column is removed from the mounting hole, and the lower portion of the new support column is inserted into the mounting hole for replacement. And since the cylinder harder than concrete is restrained by concrete, even if a support | pillar bends, a deformation | transformation is prevented and a new support | pillar can be inserted smoothly. Further, when the support column is bent, the upper portion of the attachment hole is formed to expand upward, so that the energy absorption efficiency by deformation is improved without causing local buckling of the support column.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, reference examples of the present invention will be described with reference to the accompanying drawings. FIGS. 1 to 7 show a first embodiment of the present invention. An avalanche / falling rock protection fence, which is an impact absorbing fence, is provided with a concrete foundation 1 along a slope or a road along the slope, and the concrete foundation. 1, a plurality of support columns 2 and 2A are erected at equal intervals in the left-right direction. In FIG. 1, it is shown side by side with the support columns 2, 2 </ b> A, 2 from the left side in the drawing, but further on the left side is continuous with the support columns 2 </ b> A, 2, 2 </ b> A. The support columns 2 and 2A are made of a hollow steel pipe or the like, and the lower end thereof is attached to the foundation 1, and the support column 2 is provided with a fixing unit 3 shown in FIG. 2 and FIG. The support column 2 is provided in a plurality of stages, for example, five stages. The fixing unit 3 forms a base frame 4 having a substantially U-shaped cross section that is long in the left-right direction, and plate plates 5, 5 are integrally provided on the front surfaces of the left and right ends of the base frame 4. A hole 6 is formed. One end 7A of one of left and right side direction and the other direction of the guard rope 7, 8, 8A to the fixed is Sakutan bracket 9 constituting the, respectively Re its one end, an end portion of the cord end fitting 9 Is provided with a male screw rod 9A, and the male screw rod 9A is inserted into the hole 6 of the flange plate portion 5 and a nut 9B is screwed into the male screw rod 9A so that one side and the other side of the guard rope. One end portions 7 A and 8 A of 7 and 8 are fixed to the fixing portion 3. A pair of left and right metal mounting arms 10 and 10 are integrally provided on the rear surface of the base frame 4 by welding, and the engagement grooves 10A and 10A formed at the base ends of the mounting arms 10 and 10 have the In a state where the front plate portion 12 of the support column 2 is inserted and arranged, the fixing unit 3 is detachably fixed to the support column 2 by an attachment member 11 such as a bolt. In the figure, reference numeral 13 denotes a cover that covers the front surface of the fixing unit 3. Further, the left end support column 2 in FIG. 1 becomes a support column of the falling rock guard fence, and the left end support column 2 is also provided with the fixing unit 3 as a fixing unit of the terminal, and the fixing unit 3 has a guard in the other direction. Only one end 8A of the rope 8 is fixed via the rope end fitting 9, and one end of the guard rope 7 in one side direction is fixed to the fixing portion 3 in the right end column of the falling rock protection fence not shown in FIG. Only the portion 7 </ b> A is fixed through the cable end fitting 9.
[0011]
A base frame 21 having a substantially U-shaped cross section shown in FIGS. 4 and 5 is provided in a plurality of stages, for example, five stages, on the support 2A positioned between the fixing units 3 and 3. The pair of mounting arms 10 and 10 are integrally formed on the rear surface of the base frame 21 by welding, and the engagement grooves 10A and 10A formed at the base ends of the mounting arms 10 and 10 are provided with the support columns 2 and 10A. In a state where the front plate portion 12 is inserted and arranged, the base frame 21 is fixed to the support column 2 by a bolt attachment member 11 or the like. Tightening members 22 and 22 are detachably provided at both ends of the base frame 21, respectively, and this fastening member 22 is used by screwing a nut 25 to a U bolt 23 via a stop plate 24. The both ends of the U-bolt 23 are inserted into holes 26 formed on both end sides of the base frame 21, and the nut 25 is screwed on the rear surface. Further, the one side and the other side guard ropes 7 and 8 having the one end portions 7A and 8A fixed by the fixing portion 3 are located at the front end portions of the base frame 21 located between the adjacent fixing portions 3 and 3. 7B and 8B are overlapped with each other to form an overlapping portion 27, and this overlapping portion 27 is positioned between the fastening members 22 and 22 provided on the base frame 21 and the fastening members 22 and 22 with a gap H therebetween. The fastening members 22 are arranged with a predetermined fastening force. Terminal protrusions 28 and 29 are fixed to the ends of the guard ropes 7 and 8 extending from the tightening members 22 and 22 in the one side direction and the other side direction, respectively. In the figure, reference numeral 13A denotes a cover that covers the front surface of the base frame 21. Further, as shown in FIG. 6, the guard ropes 7 and 8 are formed by twisting a plurality of steel strands to form a lasso 30 and further twisting a plurality of lasso 30. The lasso 30 located on the outer circumference of the ropes 7 and 8 has a spiral shape, and the lasso 30 on the outer circumference is twisted in a spiral shape 360 degrees from one side position in the cross section of the guide rope to reach the one side position in the cross section again. The reaching stranded wire pitch P and the interval H are made equal. Reference numeral 31 denotes a spacing member made of a plate or the like that is attached to the plurality of guard ropes 7 and 8 and holds the spacing between the guard ropes 7 and 8. Further, a net 33 made of a wire mesh or the like is stretched between the support columns 2 and 2A via upper and lower rope members 32. The net 33 is attached to a fixture (not shown) such as a clip, a wire or a band wire. ) Is attached to the front surface of the guard ropes 7,8.
[0012]
In addition, this shock absorbing fence uses a guard rope unit U in which the guard ropes 7 and 8, the base frame 21, the mounting arm 10 and a plurality of fastening members 22 are integrally assembled at the factory. In U, the end portions 7B and 8B of the guard ropes 7 and 8 are overlapped in advance at the factory to form an overlapping portion 27, and the overlapping portion 27 is tightened with the fastening members 22 and 22 provided on the base frame 21 and these tightening members. The fastening members 22 and 22 located between the members 22 and 22 and arranged with a space H are fastened with a predetermined fastening force, and the mounting arm 10 is welded to the rear surface of the base frame 21 at the factory. The cable end fittings 9 are fixed to the one end portions 7A and 8A of the guard ropes 7 and 8, respectively.
[0013]
Then, after fixing the fixing unit 3 to the column 2 at the site, the guard rope unit U is mounted between the columns 2 and 2, and in this case, the engaging groove 10A of the mounting arm 10 is aligned with the front plate 12 of the column 2A. The base frame 21 is inserted and arranged from above the support 2A and fixed at a predetermined height by bolts 11 or welding. Thereafter, the end portions 7A and 8A of the guard ropes 7 and 8 positioned at both ends of the guard rope unit U are fixed to the corresponding fixing portions 3, respectively. Then, the male screw rods 9A at both ends are inserted into the holes 6 and the nuts 9B are screwed into the inserted tips, whereby the one end portions 7A, 8A of the guard ropes 7, 8 can be easily fixed. Thus, after attaching the guard rope unit U to each predetermined place, the net 33 is attached. When an impact force is applied to the net body 33 due to falling rocks or the like, a tensile force acts on the guard ropes 7 and 8, and when the tensile force exceeds a predetermined value, that is, exceeds the limit static frictional resistance by the tightening member 22, the guard ropes 7 and 8 The one end portions 7B and 8B of 8 are frictionally slid, and a considerable amount of energy loss is generated by this friction, thereby absorbing the impact force. At the same time, the impact force is absorbed by the frictional sliding between the one end portions 7B and 8B and the fastening member 22. When the impact force is absorbed by the frictional sliding of the overlapping portion 27 and then recovered, the tightening member 22 is loosened to form the overlapping portion 27, and the tightening member 22 is fastened with a predetermined tightening force. Can only be recovered. Furthermore, the impact force of falling rocks is large, the overlapping portion 27 is frictionally slid and the terminal protrusions 28 and 29 are locked to the tightening member 22, and then a tensile force is applied to the guard ropes 7 and 8 to If the guard ropes 7 and 8 are stretched or cut due to plastic deformation, the guard ropes 7 and 8 between the fixing portions 3 and 3 where the stretched or cut portions are located are replaced and repaired. can do. When the guard ropes 7 and 8 are plastically deformed, that is, stretched, the impact force can be absorbed by the tensile stress of the guard ropes 7 and 8. In this case, the overlapping portion 27 slides and the terminal projection 28 Since the effective lengths of the guard ropes 7 and 8 between the support columns 2 and 2 are increased by the amount of movement until the 29 and 29 are locked to the tightening member 22, compared with the conventional guard rope having only the length between the support columns. The impact force absorption capacity can be increased. Further, after the overlapping portion 27 slides by the impact force and the terminal projections 28 and 29 are locked to the fastening member 22, the impact force is further absorbed by the deformation of the support columns 2 and 2A.
[0014]
Next, the support structure for supporting the rock fall protection fence will be described with reference to FIGS. 1 and 7. A support mounting hole 51 is formed in the foundation 1, and the inner surface of the support mounting hole 51 is formed on the inner surface. An inner cylinder 52 in which the lower part of the support columns 2 and 2A can be inserted and removed is provided, and a bottom part 53 is integrally provided at the lower part of the inner cylinder 52. The inner cylinder 52 and the bottom part 53 are made of steel, cast iron, It is made of a material harder than the foundation 1 such as stainless steel or high-strength concrete. The support columns 2 and 2A are inserted into the inner cylinder 52 and attached to the foundation 1.
[0015]
In the rock fall protection fence in which the pillars 2 and 2A are attached to the foundation 1 in this way, impact force such as rock fall is applied as described above, or rock falls collide with the pillars 2 and 2A. , 2A is bent, only the bent support columns 2 and 2A are pulled out, and the lower portions of the new support columns 2 and 2A are inserted into the support mounting holes 51 for installation. In this example, since the fixing unit 3 is detachably provided on the support columns 2 and 2A by the mounting member 11, the fixing unit 3 can be mounted on the replaced support columns 2 and 2A. Further, an inner cylinder 52 that is harder than concrete is provided on the inner periphery of the column mounting hole 51, and the periphery of the inner cylinder 52 is restrained by the concrete of the foundation 1, so that the columns 2 and 2A are bent. However, since the deformation of the inner cylinder 52 of the mounting hole 51 can be prevented and the inner cylinder 52 is not deformed, the support columns 2 and 2A can be exchanged smoothly.
[0016]
Thus, in the present reference example, the post mounting structure of avalanches, rockfall protection member attaching the standoff 2,2A underlying 1 made of concrete, a hard cylindrical body 52 from the foundation 1 in the post mounting hole 51 of the foundation 1 Since the lower part of the columns 2 and 2A is detachably attached to the cylindrical body 52, if the columns 2 and 2A are bent and deformed, the lower part of the columns 2 and 2A is removed from the mounting hole 51. The lower part of the new struts 2 and 2A can be inserted into the mounting holes 51 for replacement, and since the cylinder 52, which is harder than concrete, is restrained by the concrete, even if the struts 2 and 2A bend The deformation of the cylinder can be prevented, and the concrete around the mounting hole 51 can be prevented from being damaged, so that the new support columns 2 and 2A can be inserted smoothly.
[0017]
FIG. 8 shows a first embodiment of the present invention. The same reference numerals are given to the same parts as those in the above-mentioned reference example, and detailed description thereof will be omitted. In this example, the upper part of the inner cylinder 52 is arranged upward. An enlarged portion 52A is formed that expands in a curved shape. That is, the enlarged portion 52A has a trumpet shape.
[0018]
And also in this example, the support | pillars 2 and 2A can be inserted in and removed from the foundation 1 and attached. Further, even when the columns 2 and 2A bend due to falling rocks from the front direction indicated by the arrow R, the front of the columns 2 and 2A is not deformed so that the columns 2 and 2A are bent at the upper surface of the foundation 1. The S side is deformed by a tensile force, the back H side is deformed by a compressive force, and the struts 2 and 2A are deformed so as to bend, so that the rock fall energy can be efficiently absorbed by the deformation. As described above, the support pillars 2, 2 </ b> A are bent by the falling rock from the front surface S side so as to fall to the rear surface H side.
[0019]
Thus, in this embodiment, in accordance with claim 1 , in the support structure of the avalanche / falling rock protection structure in which the supports 2 and 2A are attached to the concrete foundation 1, the support pillar 51 is inserted into the support hole 51 for the support of the foundation 1. 2 and 2 are attached, and the upper part of the mounting hole 51 is formed so that the back surface H side of the support pillars 2 and 2A is enlarged upward. Therefore, when the support pillars 2 and 2A are bent, the upper part of the attachment hole 51 is upward. Therefore, energy absorption efficiency due to deformation can be improved without causing local buckling on the back surface H side of the support columns 2 and 2A. Further, since the upper portion of the attachment hole 51 is formed to be enlarged, the enlarged portion 52A serves as a guide, and the lower portions of the support columns 2 and 2A can be smoothly inserted.
[0020]
In this way, in this embodiment, corresponding to claim 2 , in the support structure of the avalanche / falling rock protector for attaching the supports 2 and 2A to the concrete base 1, the support holes 51 for the support 1 of the foundation 1 are provided. A cylindrical body 52 that is harder than the foundation 1 is provided, and the lower portions of the support columns 2 and 2A are detachably attached to the cylindrical body 52. The upper portion of the cylindrical body 52 is at least on the back H side of the support columns 2 and 2A. If the pillars 2 and 2A are bent and deformed, the lower part of the pillars 2 and 2A are removed from the attachment holes 51, and the lower parts of the new pillars 2 and 2A are inserted into the attachment holes 51. In addition, since the cylinder 52, which is harder than concrete, is restrained by the concrete, deformation is prevented even if the columns 2 and 2A are bent, and the new columns 2 and 2A are smoothly inserted. Can be worn. Further, when the support pillars 2 and 2A are bent, the upper part of the mounting hole 51 is enlarged upward, so that local buckling does not occur on the back surface H side of the support pillars 2 and 2A, and deformation occurs. Energy absorption efficiency is improved.
[0021]
Further, as an effect of the embodiment, since the enlarged portion 52A has a shape that expands upward in a curved shape, buckling on the back surface H side of the columns 2 and 2A can be reduced.
[0022]
FIG. 9 shows a second embodiment of the present invention. The same reference numerals are given to the same parts as those in the above-mentioned reference example and the embodiment, and detailed description thereof will be omitted. The base 1 is provided on the slope 61, the support mounting hole 51 is provided in the base 1, and a support 62 made of a hollow steel pipe is inserted into the support mounting hole 51 by inserting the lower part thereof. A plurality of cross beams 63 are installed on the front S side of the plurality of columns 62. Further, as shown in the figure, the cylindrical body 52 is formed with an enlarged portion 52A on the back surface H side.
[0023]
Thus in this embodiment, the lower the detachably inserted and attached to the base 1 of the strut 61, from the inner cylinder 52 has an enlarged portion 52A, corresponding to claim 1-2, in the first embodiment It has the same action and effect.
[0024]
The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the gist of the present invention. For example, in the embodiment, a cylindrical column is shown. Further, the inside of the support column can be filled with a filler such as concrete, and the support column can be solid. In addition, the material of the support can be selected as appropriate, and the inner cylinder is harder than the support, which is preferable for repeated replacement of the support, but since the outside of the inner cylinder is constrained by concrete, the inner cylinder is not necessarily the support. The material need not be harder, and the material can be appropriately selected as long as it is harder than the concrete concrete. Further, the enlarged portion is not necessarily curved.
[0025]
【The invention's effect】
According to the first aspect of the present invention, in the support structure for an avalanche / falling rock protection body in which the support is attached to a concrete foundation, the lower part of the support is attached to the support hole for the support of the foundation, and the upper part of the attachment hole is at least The back side of the column is enlarged upward, and an avalanche / falling rock protector column mounting structure with excellent energy absorption efficiency due to deformation of the column can be provided.
[0026]
Invention 請 Motomeko 2, in post mounting structure of avalanches, rockfall protection member attaching the post to concrete foundation, a hard cylindrical body from said base is provided to the strut mounting hole of said base, it said in the cylindrical body The lower part of the column is removably inserted, and the upper part of the cylindrical body is formed such that at least the back side of the column is enlarged upward, the column can be easily replaced, and energy is absorbed by deformation of the column. It is possible to provide an avalanche / falling rock protector column mounting structure with excellent efficiency.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a reference example of the present invention.
FIG. 2 is a cross-sectional view of the front side of a fixing unit showing a reference example of the present invention.
FIG. 3 is a side sectional view of a fixing unit showing a reference example of the present invention.
FIG. 4 is a plan sectional view of an overlapping portion showing a reference example of the present invention.
FIG. 5 is a side sectional view of an overlapping portion showing a reference example of the present invention.
FIG. 6 is a perspective view of a guard rope showing a reference example of the present invention.
FIG. 7 is a cross-sectional view of a column mounting structure showing a reference example of the present invention.
FIG. 8 is a cross-sectional view of the support mounting structure showing the first embodiment of the present invention.
FIG. 9 is a cross-sectional view of a protective wall support mounting structure showing a second embodiment of the present invention.
FIG. 10 is a cross-sectional view of a conventional column mounting structure.
[Explanation of symbols]
1 Foundation 2, 2A Prop
51 Prop mounting holes
52 cylinder
52A Enlarged part

Claims (2)

In the support structure of the avalanche and rockfall protection body with the support attached to the concrete foundation, the lower part of the support is attached to the support hole for the support of the foundation, and at least the back side of the support is directed upward at the upper part of the attachment hole. An avalanche / falling rock protector mounting structure, characterized in that it is enlarged . In the support structure of the avalanche / falling rock protection structure where the support is attached to a concrete foundation, a cylindrical body harder than the foundation is provided in the support hole for the support of the foundation, and the lower part of the support is inserted in this cylinder so that it can be attached and detached. An avalanche / falling rock protector support mounting structure, characterized in that the upper part of the cylindrical body is formed such that at least the back side of the support is enlarged upward .

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