JP2004162486A - Guard fence - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a guard fence 10 deformed little by snow pressure or the like even if installed in a heavy snowfall area, and constituted not to require much time and cost for repair work. <P>SOLUTION: This guard fence 10 is constituted by stretching a protective net 30 between posts 20, 20 erected at prescribed spaces, and the upper half of the guard fence 10 is separable and connectable. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a protective fence for stopping a falling vehicle, an avalanche, or an overrunning traveling vehicle.
[0002]
[Prior art]
Protective fences are provided along the slopes and on the side of roads.Wire ropes and protective nets are laid between columns erected at predetermined intervals, and collision energy is provided by elastic deformation of the provided metal fittings with shock absorbers and wire ropes. It absorbs and when it exceeds a certain receiving force, it is absorbed by the plastic deformation of the column, etc., and most of them are erected as permanent structures.
[0003]
[Problems to be solved by the invention]
The above-mentioned conventional protective fence has the following problems.
<B> When the protective fence is installed in a heavy snowfall area, the protective fence is deformed due to snow pressure, sliding, sinking force, avalanche, etc. of snow. Therefore, it takes a lot of time and cost for repair work after the thaw.
<B> Due to concerns about deformation of the protective fence due to snow, the protective fence may be dismantled before arrival in the snowfall season. However, dismantling and assembling costs are required every year, and the original protection performance is sacrificed against falling rocks that are likely to occur during snow melting.
[0004]
[Object of the invention]
The present invention has been made in order to solve the above-mentioned conventional problems.Even when a protective fence is installed in a heavy snowfall area, there is little deformation due to snow pressure or the like, and a great deal of time and cost is required for repair and repair work. The purpose is to provide a protective fence that does not cover.
It is another object of the present invention to provide a protective fence that is less likely to be deformed by snow pressure or the like while maintaining the original purpose of capturing rockfall.
The present invention achieves at least one of these objects.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, a protective fence according to the present invention is a protective fence in which a protective net is erected between columns erected at predetermined intervals, and the upper half of the protective fence is separated and connected. This is a protective fence that has been made possible.
Here, the upper half includes a case where the image is divided into two or more.
[0006]
Further, the protective fence of the present invention is characterized in that the above-mentioned protective fence is configured such that the support column is divided and a hinge mechanism is provided at the divided portion so that the upper half of the protective fence can be turned upside down. Is what you do.
[0007]
Further, the protective fence of the present invention is characterized in that the protective fence is constructed such that it can be integrated and disassembled with an unbonded PC material continuously penetrated between the divided columns.
[0008]
Embodiment 1 of the present invention
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0009]
<A> Configuration of the protective fence FIG. 1 is a perspective view of the protective fence 10, which is partially cut away, looking up from the valley side to the mountain side.
As an example of the protective fence 10 according to the present invention, a plurality of pillars 20 erected at predetermined intervals, and a protective loop 31 wrapped in a loop between these pillars 20 and 20 and laid horizontally. A protection net 30 including a frictional resistance type shock absorber 32 (FIG. 4) gripping the vicinity of an end of the protection loop 31 will be described as a basic component (FIG. 2).
In this example, a description will be given of a case where the upper portions of the columns 20 are connected by a horizontal rod 40 and a diamond-shaped wire mesh 33 is attached to one surface of the protection loop 31. However, the horizontal rod 40 and the wire mesh 33 may be omitted.
[0010]
<B> The support column 20 is configured to be vertically separable by a joint means 21 provided at a predetermined height, and includes a column lower portion 20b installed in the ground and a column upper portion 20a connected to an upper portion of the column lower portion 20b. .
The joint means 21 is a mechanism for surely transmitting the forces applied to the upper and lower columns 20a and 20b to each other, and is configured to be freely divided and assembled. For example, flanges 21a and 21b may be arranged at the lower end of the upper column 20a and the upper end of the lower column 20b, respectively, and connected by bolts and nuts 21c.
With this configuration, the connection and division can be repeatedly performed.
[0011]
As shown in FIG. 3 in an enlarged manner, the column 20 is, for example, a steel tube, a concrete-filled steel tube, a concrete column, an elastic column, or the like, and may be formed as a curved surface on which a protection loop 31 to be described later is to be wound.
U-shaped positioning projections 312 are provided on the side surface of the support column 20 in multiple stages along the length direction, and the protective loop 31 is inserted through each positioning projection 312 to prevent slipping. In this example, a form in which the head of the support 20 and the ground in the passive direction are connected by the stay rope 50 will be described.
[0012]
<C> Protective net The protective net 30 receives an impact force directly or indirectly from a falling rock or the like, buffers the impact force, and stops falling objects such as a falling rock. In this example, the protection net 30 has a loop shape. It comprises a protective loop 31 wound around and suspended, and a frictional resistance type shock absorber 32 gripping near the end of the protective loop 31.
[0013]
The protective loop 31 is made of, for example, a rope made of a PC steel wire or a PC twisted steel wire. The protective loop 31 is wound around each of the adjacent columns 20, 20 in a loop shape without slack in the horizontal direction without any slack. It is gripped by the buffer 32 (FIG. 2).
The rope range extending from the gripping position of the shock absorber 32 of each protection loop 31 is formed as extra lengths 311 and 311, and the protection loop 31 slides (slip) at the time of receiving by the set length of the extra lengths 311 and 311. ) The distance is determined.
[0014]
In the case where there are three or more columns 20, the protective loops 31, 31 are wound around the columns 20, which are located between the terminal columns, from both directions except for the column of the terminal, and the columns 20 are divided into the left and right protective loops 31, 31, respectively. The protection loops 31 are wrapped in a chain so as to be in a shared relationship with respect to.
[0015]
On the plurality of protective loops 31, 31... Disposed on the support column 20, a wavy strip-shaped or rod-shaped cross member 34 is disposed, and the intersection thereof is formed by a rectangular receiving plate 343 and a U-bolt as shown in FIG. 7. 341 and a nut 342.
[0016]
The shock absorber 32 for holding the overlapping portion of the protection loop 31 and allowing the rope to slide when the tensile force acting on the protection loop 31 exceeds the frictional resistance of the holding portion to attenuate the impact force is provided. For example, as shown in FIG. 4, a restraining plate 321 formed by folding the center of a spring steel plate to form a bulb-shaped cross section, and a partition that is inserted into the restraining plate 321 to bisect the inner space and define a space for accommodating the rope 31. It comprises a plurality of bolts 323 and nuts 324 which fasten the plate 322 and the free end of the restraining plate 321 in the contraction direction, and tighten the protective rope 31 by contacting the protective rope 31 with the restraining plate 321 and the partition plate 322.
Then, the tightening force of the bolt 323 applied to the restricting plate 321 is applied as an equal restricting force to the ropes 31, 31, and the contact between the restricting plate 321 and the partition plate 322 pressed against the peripheral surface of each rope 31. The structure is such that the tensile force acting on the rope can be attenuated by the frictional resistance of the part.
[0017]
As the shock absorber 32, a well-known friction resistance shock absorber including a plurality of plate members capable of gripping the overlapping portion of the protective loop 31 and bolts capable of fastening between the plate members can be used in addition to the illustrated members. It is.
[0018]
[Action]
<A> During normal use Next, when various impact forces F act on the protective fence 10 from the upper side to the lower side in FIG. 6, the impact force F is applied to the front surface of the protective loop 31 arranged in multiple stages via the wire mesh 33. The impact force F acts on (the side on which the shock absorber 32 is not provided).
This impact force F is transmitted to the rear surface of the protection loop 31 (the side provided with the shock absorber 32) through the portion wound around the column 20, and acts as a uniform pulling force over the entire length of the protection loop 31.
Further, since the cross member 34 intersects with the plurality of protection loops 31, 31... Arranged in multiple stages and is divided into small sections, even a falling rock having a small impact force F can be received without being transmitted.
As long as the pulling force does not exceed the gripping force of the shock absorber 32 of the protection loop 31, sliding does not occur on the rope, so that the loop length of the protection loop 31 does not change.
When the impact force F exceeds the gripping force of the shock absorber 32, it slides (slips) between the rope constituting the protection loop 31 and the shock absorber 32, and the shock force F is effectively reduced by the frictional resistance during the sliding. Absorb.
[0019]
With the start of the sliding between the rope and the buffer 32, the loop length of the protection loop 31 becomes longer, and the sliding occurs also at the winding portion between the protection loop 31 and the side surface of the support 20. The absorbing effect of the impact force F also progresses due to the frictional resistance of the winding portion.
[0020]
When the impact force F exceeds the deformation strength of the transverse member 34, the transverse member 34 is deformed and stretched by a certain length as shown in FIG. 7, and the impact force F is absorbed by the deformation resistance.
Further, of the protective loops 31 arranged in multiple stages, the cross member 34 disposed on the collision side also has a function of contacting the protective rope 31 on the back side and restricting further protrusion.
[0021]
Further, as will be described later, the protection fence 10 according to the present invention requires a small amount of protrusion of the protection loop 31 to the side.
[0022]
FIG. 8 is a model diagram of a single-type protection fence for comparison in which a rope is arranged with one end fixed to each support and the center of the overlapping portion of both ropes is gripped by a buffer (not shown).
(A) of the same figure shows the state before receiving, and (B) of the same figure shows the state after receiving. Distance L, for example, 6m between struts, and the distance l of extra length portion of the rope was 0.5 m, bulging amount [Delta] y ₁ rope after受撃becomes 1.25 m.
[0023]
FIG. 9 shows a model diagram of the protective fence according to the present invention in which the protective loop 31 is stretched between the columns. FIG. This shows the state after the shot.
Distance L, for example, 6m between struts, and the distance l of extra length portion of the rope was 0.5 m, bulging amount [Delta] y ₂ ropes after受撃becomes 0.875 m. However, in order to simplify the calculation, the length of the portion where the protection loop 31 is wound is ignored.
[0024]
As described above, the amount of the overhang of the rope in the case where the sliding amount (the amount of energy absorption) is the same is smaller in the protection loop 31 as in the present invention, which is advantageous when the protection fence 10 is installed near a road or the like.
Further, the protective fence 10 according to the present invention can not only reduce the diameter of the rope but also excel in shear strength as compared with the single type.
As described above, when the protection fence 10 receives an impact force, the protection fence exhibits the above-described protection function.
[0025]
<B> In winter use, before snowfall, the upper half of the protective fence 10 is dismantled and removed according to the following procedure.
[0026]
The stay rope 50 that supports the standing of the protective fence 10 is removed, and the protective loop 31 and the wire mesh 33 that are stretched on the support 20 are released from the tension within a required range.
In this example, the range to be released is set to a position slightly lower than the joint means 21 from the upper end of the column 20.
The protection loop 31 within this range is removed from the support 20 together with the shock absorber 32, and the lower half of the protection loop 31 is left as it is on the lower part 20b of the support. In this way, the protection net 30 is divided and used.
At this time, the wire mesh 33 having a planar shape may be used while the lower half is fixed to the column lower part 20b and the released upper half is folded back toward the receiving side, or may be completely removed from the protective loop 31. Is also good.
In addition, these orders are not necessarily limited to the above.
[0027]
The bolts 21c for fastening the flanges 21a and 21b of the upper and lower columns 20a and 20b are released, and the connection between the upper and lower columns 20a and 20b is disconnected (FIG. 10). Thus, the upper column support 20a is removed from the lower column support 20b.
The removed support upper part 20a is moved to another location and stored together with the removed protection loop 31.
[0028]
When the protection loop 31 and the wire mesh 33 are left at a high position, the load received from snow and avalanches increases, and the protection fence 10 is easily deformed. On the other hand, if the height of the protective fence 10 is reduced in consideration of deformation, the falling height of falling rocks decreases. The height at which the protection loop 31 and the wire netting 32 are left is appropriately determined in consideration of these points from the installation location of the protection fence 10. In any case, since the height of the remaining protective fence 10 is lower than before, the possibility that the protective fence 10 is deformed due to the snow pressure, sliding, sinking force and avalanche of snow is reduced, and the height of the remaining fence is reduced. Within the range, the function as the conventional protective fence 10 can be functioned.
This leads to prevention of deformation and breakage of not only the pillar 20 but also the wire netting 33 and the protection loop 31, and it is economical because breakage of the foundation concrete can be prevented.
Further, unlike the conventional method in which the protective fence 10 is completely removed, the lower half of the protective fence 10 is left, so that the security can be maintained without being completely vulnerable.
In particular, since the ground often sags on a slope after snow melting, this form is optimal.
As described above, the form in which the protection loop 31 and the wire mesh 33 in the lower half of the protection fence 10 are left has been described. However, the form in which these 31 and 33 are removed and only the support pillar lower part 20b is erected may be adopted.
[0029]
Embodiment 2 of the present invention
In the above, the protection fence 10 in which the joint means 21 of the column 20 is a flange connection has been described. However, a form in which the columns 20a and 20b are configured to be separable and connectable using the PC material 22 will be described.
Note that the division of the protection net 30 is the same as in the first embodiment, and a description thereof will be omitted.
[0030]
As shown in FIG. 11, the support 20 has an unbonded type prestress structure in which a sheath tube 23 is disposed in a steel pipe, a PC material 22 is inserted therein, and concrete is filled.
The PC material 22 is disposed on the tension side, that is, the impact side, or the entire circumference of the steel pipe, and is protruded from both ends of the column 20 and is fixed with a known stopper 24. The body 25 is fixed as a reaction force source, and connects the upper column 20a and the lower column 20b.
Also, the PC material 22 is not pre-tensioned, but is set to such a degree that there is no slack, and the tension can be introduced into the PC material 22 when the column 20 is deformed. For example, the load-carrying capacity and deformation capacity (toughness) of the column 20 can be improved in each step.
[0031]
When removing the support | pillar upper part 20a in this form, the stopper 24 of the support | pillar upper part 20a side is removed. After removing the upper column 20a, the PC member 22 projects from the upper end of the lower column 20b. Therefore, similarly to the column 20, the PC member 22 is also provided with a splitter, such as a coupler, which can be divided up and down. It is good also as a form which can remove the PC material 22 located. In addition, the PC member 22 in a single shape may be configured to be able to be extracted from the support 20 by a method such as a screw-in type.
[0032]
In order to maintain the upright posture of the column 20 with the stopper 24 removed, and to maintain the connection between the upper and lower columns 20a, 20b during use, for example, a flange-like steel plate having holes at the dividing positions of the columns 20 is used. The steel plates may be arranged and connected by bolts and nuts.
[0033]
Conversely, when connecting the upper column 20a to the lower column 20b, the connecting member 26 temporarily fixes the upper and lower columns 20a, 20b, and the PC member 22 protrudes from the mating surface of the lower column 20b to the sheath tube 23 of the upper column 20a. Is inserted, and the PC member 22 protruding from the opposite side is fixed with the stopper 24.
In other words, the PC member 22 serves as a substitute for the bolt of the first embodiment, and also provides a tension to the column 20 to improve the structural strength.
When connecting the columns 20a and 20b, a tension may be applied to the PC member 22.
[0034]
Third Embodiment of the Invention
In the above, the form in which the support upper part 20a is completely separated from the support lower part 20b has been described. However, the support upper part 20a does not necessarily need to be separated, and the joint part may be configured as a hinge mechanism to form a center-fold type. 13 and 14).
[0035]
In the hinge mechanism, for example, a hinge 27 is arranged on the peripheral side surface of the column 20 so that the column upper portion 20a can be tilted (FIG. 12).
The hinge 27 is configured so that the forces received by the upper and lower columns 20a and 20b can be transmitted to each other when the column 20 is raised and tilted, and does not become a weak point when receiving energy.
In addition, a hook 28 is provided around the peripheral side surface of the column 20 except for the mounting position of the hinge 27 to prevent the column upper portion 20a from tilting.
[0036]
The hinge 27 is arranged on the receiving side, that is, on the mountain side of the peripheral side surface of the column 20, and tilts the upper half of the protective fence 10 toward the mountain side (FIG. 13).
By tilting the upper half of the protection fence 10 toward the receiving side, the resistance strength of the protection fence 10 against impact energy is doubled or more, and the deformation resistance of the column 20, the protection loop 31, and the like is improved. This is because not only is the protective fence 10 doubly juxtaposed to the direction of the impact force, but also the bent pillar 20 has two support points on the ground, thereby forming a triangle and indeterminate. And the resistance to the receiving force increases, and the force can be transmitted to the ground surface.
Further, the hinge 27 may be provided on the valley side of the peripheral side surface of the column 20, and the upper half of the protective fence 10 may be tilted to the downstream side as shown in FIG. In this case, the tilted protective fence 10 can be used as the support member 10a, and the transmission efficiency can be further improved by arranging the stopper 60 at the contact portion between the support member 10a and the ground.
[0037]
By making the joint part a hinge mechanism, it is not necessary to carry out the upper part 20a of the support column and the protective loop 31, and the transportation cost is reduced.
At this time, the protective loop 31 and the wire mesh 33 disposed on the support 20 do not necessarily need to be disposed on the support 20, but may be bent together with the support upper portion 20a in a state where the protection loop 31 and the wire mesh 33 are removed or tension is released.
[0038]
Embodiment 4 of the present invention
Further, the protective net 30 of the present invention may be made of various types of ropes, wire nets, or a combination thereof.
The present invention can be applied to a general-purpose protective fence made of an H-shaped steel, a wire rope, and a wire mesh, and there is no particular restriction on the material and the cross-sectional shape.
As described above, the present invention can be applied to a protective fence provided with various supports and various protective nets.
When the fence is large and the height of the column 20 is high, the column may be divided into three or more. In the present invention, the “upper half” includes two or more divisions.
[0039]
【The invention's effect】
Since the protective fence of the present invention is as described above, the following effects can be obtained.
<A> The protective fence of the present invention has a configuration in which the upper half of the protective fence can be separated and connected. Therefore, when installing in heavy snowfall areas, the upper half of the protective fence is separated during the winter season and only the lower half is separated, so that the risk of deformation due to snow pressure, sliding, sinking force and avalanche of the snow cover is reduced. It is an economical fence that does not require any time or cost for repair work due to deformation.
<B> During the winter season, the lower half of the pillar is left behind to maintain a certain level of safety from falling rocks, and is a protective fence that is less likely to be affected by snow pressure or the like.
<C> Even if replacement is necessary, it is economical because only half of the columns are needed.
<D> By providing the hinge mechanism at the divided portion of the column, the upper half can be turned upside down, and disassembly and assembly are facilitated. In addition, the protective fence having a triangular cross section becomes indeterminate, resulting in an increase in resistance to impact energy and an increase in deformation resistance.
[Brief description of the drawings]
FIG. 1 is an explanatory view of Embodiment 1 of a protective fence of the present invention when looking up from a Tanigawa to a mountain side.
FIG. 2 is a front view of Embodiment 1 of the protective fence of the present invention.
FIG. 3 is a perspective view of a part of the support pillar and a protection loop around which a part is omitted.
FIG. 4 is a perspective view of a shock absorber.
FIG. 5 is an explanatory view of a form in which a protective rope is wound between supports.
FIG. 6 is an explanatory view of the operation of the protective fence.
FIG. 7 is a sectional view of a protective rope subjected to an impact.
8A and 8B are model diagrams for explaining the amount of overhang of the rope of the comparison fence, wherein FIG. 8A is a model diagram before receiving, and FIG. 8B is a model diagram after receiving.
9A and 9B are model diagrams for explaining the amount of overhang of the protection loop, wherein FIG. 9A is a model diagram before receiving, and FIG. 9B is a model diagram after receiving.
FIG. 10 is an explanatory view when the upper portion of the support of the first embodiment is removed.
FIG. 11 is a sectional view of a column according to the second embodiment.
FIG. 12 is an enlarged explanatory view of a divided portion of a column according to the third embodiment.
FIG. 13 is a side view in which the upper part of the protective fence according to the third embodiment is inclined to the mountain side.
FIG. 14 is a side view in which the upper part of the protective fence according to the third embodiment is tilted toward the valley side.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Protective fence 20 ... Prop 20a ... Prop upper 20b ... Prop lower 30 ... Protective net 31 ... Protective loop 32 ... Buffer 33 ... Wire mesh 40 ... Horizontal pole

Claims (3)

In a protective fence consisting of a protective net erected between columns erected at predetermined intervals,
Characterized in that the upper half of the guard fence can be separated and connected.
Guard fence. 2. The protective fence according to claim 1, wherein the support post is divided and a hinge mechanism is provided at the divided portion so that the upper half of the protective fence can be turned upside down. The protective fence according to claim 1 or 2, wherein the protective fence is configured to be integrated and dismantled by an unbonded PC material continuously penetrated between the divided columns.

Images