JP6393850B1 - Standing structure of support column in guard fence - Google Patents

Abstract

[PROBLEMS] To erect a support post in a protective fence that can relieve stress concentration on the lower part of the support post during impact to prevent early deformation and buckling of the support post and can fully exhibit the shock absorbing performance inherent to the protective fence. Provide structure. A lower portion of a support column is erected on a slope G through a ground plate, and the ground plate can be slid to a ground plate anchor through a plurality of slide holes formed in the ground plate. The lower part of the support | pillar 10 is standingly arranged so that it can slide toward the specific direction of the slope G with the ground plate 30 at the time of receiving. [Selection] Figure 2

Description

  The present invention relates to a protective fence that stands on the slope of a hillside and the bottom of a slope and captures fallen objects such as falling rocks, earth and sand, and avalanches, and in particular, the protective fence that improves the toughness of the protective fence and enhances the shock absorption performance. It relates to the upright structure of the support in

In general, a protective fence is composed of a plurality of support columns standing upright on a slope, etc., and a protection net attached between adjacent support columns. A shock absorber is interposed in a part of the rope material constituting the frame and a part of the holding rope supporting the support.
Most of the protective nets are made of wire mesh, metal or fiber ropes, or a combination of these. Steel columns such as H steel and steel pipes, concrete-filled steel pipes, concrete-filled steel pipes embedded with PC materials, etc. are known. The material of the protective net and the column is selected according to the shock absorbing performance of the protective fence.

In general, the protective fence is a structure in which the impact force of falling objects such as falling rocks acting on the protective net is finally received by the support column, and thus the standing structure of the support column becomes important.
As a structure for standing upright, there are known a form of standing upright and a form of standing upright.
As a form to stand upright so that the pillar cannot be tilted, a form in which the lower part of the pillar is embedded in the concrete foundation (Patent Document 1) and a form in which the pillar is deeply embedded in the ground (Patent Document 2) are known. .
The structure in which the support column can be tilted is a structure in which the support column can be tilted without being embedded, and a hinge element is provided below the support column (Patent Documents 3 and 4), This is a form in which a holding rope is connected to an anchor for a strut that has been driven in, is inserted into a grounding plate and a hollow strut, and is provided at the end of the retaining rope that is led to the upper end of the strut (Patent Document 5).
In the form in which the hinge element is provided at the lower part of the support column, a shock absorber is interposed in a part of the support rope for the support column. The strut is tilted toward the valley side around the hinge element by slipping the holding rope.

Japanese Patent Laying-Open No. 2003-34912 (FIG. 2) JP 2007-205109 A (FIGS. 1 and 3) JP 2007-32032 A (FIGS. 1 and 2) JP 2009-144472 A (FIGS. 1 and 7) Japanese Patent Laying-Open No. 2001-107321 (FIG. 3)

The conventional guard fence has the following problems to be solved.
<1> As disclosed in Patent Documents 1 and 2, in the guard fence in which the column is erected so as not to tilt, the base of the column is fixed so that it cannot be displaced in order to withstand the impact force, and is transmitted to the column. It is structured to receive the impact force at a fixed position.
Therefore, the transmission time of the impact force transmitted from the protective net to the support column is very short, and the impact force momentarily acts on the support column. Therefore, the base of the support column must be It suddenly bends and cannot fully exhibit its shock absorbing performance.
<2> In the protective fence that stands upright so that the support columns disclosed in Patent Documents 3 and 4 can be tilted, the support columns tilt at the time of impact, but the impact force acts instantaneously on the base of the support columns. It is not possible to fully exhibit the shock absorbing performance that the protective fence originally has.
<3> A general flexible guard fence includes a plurality of shock absorbers, and has a structure that absorbs an impact force when the shock absorbers operate.
Although the shock absorbing performance of the protective fence is improved by using a plurality of shock absorbers, replacement of the deformable member and maintenance are required after the impact.

  The present invention was made to solve the above problems, and the object of the present invention is to relieve stress concentration on the lower part of the column at the time of impact and to suppress early deformation and buckling of the column. An object of the present invention is to provide an upright structure for supporting columns in the protective fence that can sufficiently exhibit the shock absorbing performance inherent to the protective fence.

The present invention comprises a plurality of struts erected at intervals, and a protection net stretched between the struts, and the erection of the struts in a protective fence in which the lower portion of the struts is erected on a slope via a ground plate. It is an installation structure, and the lower part of the support | pillar is standingly arranged so that it can slide toward the specific direction of a slope with a ground plate.
In another embodiment of the present invention, the ground plate has a plurality of slide holes, and the ground plate is slidably fixed to the same number of ground plate anchors as the slide holes through the plurality of slide holes. .
In another aspect of the present invention, the plurality of slide holes may be parallel to each other and formed along the inclined direction of the inclined surface, or formed along a direction orthogonal to the inclined direction of the inclined surface. Alternatively, it may be formed along the oblique direction of the slope.
In another embodiment of the present invention, the support column and the ground plate may be assembled, or the support column and the ground plate may be assembled together in advance.
In another embodiment of the present invention, the protective net is attached between adjacent struts in a span unit.

According to the present invention, the lower portion of the support column is slidably installed along with the ground plate so as to be slidable in a specific direction of the inclined surface.
Therefore, early deformation and buckling of the support can be suppressed, and the shock absorbing performance inherent to the protective fence can be sufficiently exhibited.

Perspective view of a protective fence according to the present invention, with a part omitted The exploded assembly figure of the support | pillar and ground plate which concern on Example 1 of this invention Vertical section of support and ground plate It is explanatory drawing of a support | pillar and a grounding board, (A) is a top view of the grounding board which fractured | ruptured one part, (B) is sectional drawing of BB in (A). Plane model diagram of the protective fence before the support slides in the explanatory diagram of the action of catching falling objects by the protective fence This is an explanatory diagram of the action of catching falling objects by the protective fence, and a plan model diagram of the protective fence when the column slides The top view of the grounding plate which concerns on Example 2 which formed the slide hole in the Y direction of the slope. The top view of the ground plate concerning Example 3 which formed the slide hole diagonally

The present invention will be described below with reference to the drawings.
In the description, the slope direction of the slope G is defined as the Y direction, and the direction orthogonal to the slope direction of the slope G is defined as the X direction.

[Example 1]
<1> Outline of Guard Fence Referring to FIG. 1, the present invention is a protection net stretched between a plurality of struts 10 (intermediate struts, terminal struts) erected at predetermined intervals and struts 10. The premise is a protective fence equipped with
The protection fence illustrated in this example will be described. Each column 10 is erected on the slope G via the ground plate 30.
The lower part of the column 10 can slide in the specific direction of the slope G together with the ground plate 30. In this example, a mode in which the support column 10 slides in the X direction of the slope G will be described.
The slide structure of the column 10 will be described later.

A rope net 21 made of rope and a wire net 22 having a mesh smaller than that of the rope net 21 are overlapped and bridged between the plurality of columns 10. The rope net 21 and the wire net 22 constitute a protective net 23.
Both ends of the upper and lower horizontal ropes 21 a and 21 b constituting the rope net 21 are connected to the adjacent columns 10 and 10.
The rope net 21 may be attached in units of spans of struts or may be attached across three or more struts 10. In either form, the left and right sides of the adjacent rope nets 21 are connected with a separate connecting material (such as a rope) so that the seam does not open.

Further, a rope spacing cable 24 is routed between the upper portions of the adjacent columns 10, 10, and the spacing cable 24 arranged in units of span keeps the distance between the adjacent columns 10, 10 constant. It has come to be able to do.
The wire net 22 may be attached to the interval holding cable 24 by hanging down, or may be attached to the rope net 21.

A mountain-side anchor 40 is provided directly above each column 10 or between adjacent columns 10, and a side anchor 41 is provided on the side of the column 10 of the terminal.
Known anchors such as ground anchors and lock bolts are applied to these anchors 40 and 41.

A mountain side holding rope 45 is routed between the upper part of each column 10 and the mountain side anchor 40, and a mountain side positioning rope 46 is routed between each ground plate 30 and the mountain side anchor 40.
A side retainer rope 47 is routed between the upper part of the terminal column 10 and the side anchor 41, and a side positioning rope 48 is routed between the lower part of the terminal column 10 and the side anchor 41. Has been.

  In this example, a description will be given of a type of protective fence that does not include a well-known shock-absorbing bracket on the horizontal ropes 21a and 21b that constitute the ropes 45 and 47 and the rope net 21, but it can also be applied to a guard fence that includes a shock-absorbing bracket. It is.

<2> Struts Referring to FIGS. 2 to 4, the strut 10 is moored by winding the spacing holding rope 24, the holding ropes 45 and 47, and the positioning rope 48 shown in FIG. An anti-slip pin 11 for projecting is provided.
The connecting means of the plurality of ropes is not limited to the mooring type by the detent pin 11 and may be connected to a bracket (not shown) protruding from the support column 10.

  Further, in this example, the form in which the support column 10 is configured by a hollow tube (steel pipe or the like) will be described, but the support column 10 is a known steel material (H steel or the like) or a known support column such as a filled steel tube in which a steel pipe is filled with concrete. Is included.

<3> Grounding plate The grounding plate 30 is a load transmission plate for transmitting and supporting the load acting through the support column 10 to the inclined surface G while positioning the lower portion of the support column 10.
An outer cylinder 31 that can be inserted into the lower portion of the support column 10 is projected on the upper surface of the ground plate 30, and a cylindrical rubber plate that can inscribe the lower portion of the support column 10 on the inner peripheral surface of the outer tube 31. 32 is provided.
The outer cylinder 31 is reinforced by reinforcing ribs 34 arranged radially.
The lower part of the column 10 can be assembled to the ground plate 30 by inserting the lower part of the column 10 into the rubber plate 32 and fitting it.
The outer cylinder 31 and the rubber plate 32 may be in the form of a complete cylinder, or may be a divided form in which the cylinder is vertically divided as shown in the figure.

  In this example, in order to improve the transportability of materials to the site and the workability at the site, a configuration in which the support column 10 and the ground plate 30 are constructed in an assembly manner will be described. Alternatively, they may be connected by fixing means such as screwing.

  In the present example, one end of the mountain side positioning rope 46 is connected to the connection hook 36 attached to the ground plate 30. However, even if one end of the mountain side positioning rope 46 is directly moored and connected to the lower portion of the support column 10. Good.

<4> Tension structure of support column and grounding plate Referring to FIGS. 2 to 4, the support column 10 is in a tensioned state between the support column 10 and the ground plate 30 via a tension member 50 inserted through the inside of the support column 10. It is connected with.
The tension member 50 is a rope member that can be inserted into the inside of the support column 10, and a lower portion of the tension member 50 is moored with a suspension hook 35 that stands on the ground plate 30 that is the bottom surface of the outer cylinder 31.
A tightening bolt 51 is integrally connected to the upper portion of the tension member 50, and a tightening nut is attached to the tightening bolt 51 through which an annular contact plate 52 and a spring 53, which are sequentially placed on the upper end of the column 10, are inserted. 54 is screwed.
By tightening the tightening nut 54 and tensioning the tension member 50, the column 10 and the ground plate 30 are tightly coupled, and the standing posture of the column 10 is maintained with respect to the ground plate 30.
The grounding plate 30 may be laid directly in contact with the slope G, but if placed on the height-adjusting mortar layer 44 constructed prior to the slope G, the stability of the grounding plate 30 and the bearing effect Will be better.

<5> Slide structure of the ground plate The ground plate 30 is fixed to the slope G in a state that allows the slope G to slide in the X direction at the time of receiving. The slide structure of the ground plate 30 will be described in detail with reference to FIGS.

<5.1> Slide hole of ground plate The slide structure of the ground plate 30 will be described. A plurality of slide holes 33 are formed on the plate surface of the ground plate 30 with the outer cylinder 31 interposed therebetween. The plurality of slide holes 33, 33 are parallel to each other and are arranged in parallel with the X direction of the slope G.
Since the slide distance of the ground plate 30 is determined by the total length of the slide hole 33, the total length of the slide hole 33 is appropriately selected in consideration of the shock absorbing performance of the protective fence, the installation situation at the site, and the like.

<5.2> Grounding Plate Anchor The grounding plate anchor 42 for fixing the grounding plate 30 is a known anchor such as a lock bolt, and is provided at a plurality of locations along the Y direction of the slope G.
The number of ground plate anchors 42 may be the same as the number of slide holes 33.
The ground portion of the ground plate anchor 42 is formed with a screw so that the nut 43 can be screwed, and the nut 43 is screwed onto the exposed screw portion of the ground plate anchor 42 inserted into each slide hole 33. Thus, the ground plate 30 can be fixed to the slope G.

[Protective fence behavior]
With reference to FIGS. 5 and 6, the behavior of the protective fence at the time of receiving, in particular, the behavior of the column 10 will be described. In addition, since the basic capture | acquisition effect | action of fallen objects, such as falling rocks, in a protection fence is the same as the past, the description is abbreviate | omitted here.

<1> The behavior of the strut immediately after receiving FIG. 5 shows a plan model diagram of the protective fence immediately after the impact F of the fallen object collides with the protective net 23. It is arranged in parallel with the X direction.

Immediately after the impact F acts on the protective net 23, the protective net 23 starts to bend and deform toward the valley side, and the impact F acts as a tensile force f on the adjacent struts 10, 10 through the protective net 23. To do. The tensile force acting on each column 10 acts as a displacement force f directed to the ground plane 30 in the X direction of the slope G.
When the displacement force f in the X direction of the slope G acting on the ground plate 30 is smaller than the fixing force of the ground plate 30 fixed to the ground plate anchor 42, the ground plate 30 is not displaced. That is, the standing position of the support column 10 remains the same, and the span L ₁ of the adjacent support columns 10 and 10 does not change.
Therefore, the impact energy is absorbed by the deformation resistance force of the protective net 23 and the strength of the support column 10 as in the case of the conventional protective fence.

<2> Slide of the column FIG. 6 shows a plan model diagram of the protective fence when the deformation amount of the protective net 23 increases.

When the deformation amount of the protection net 23 increases, the displacement force f in the X direction of the slope G acting on the ground plate 30 also increases.
When the displacement force f in the X direction of the slope G acting on the ground plate 30 exceeds the fixing force of the ground plate 30 fixed to the ground plate anchor 42, the ground plate 30 moves along the slide hole 33. Slide displacement toward the X direction of the inclined surface G.
That is, to vertically position the struts 10 are laterally displaced from the initial position, the span L ₂ adjacent strut 10, 10 is slightly shorter than the span L ₁ before the displacement.

  Even while the lower part of the column 10 is displaced in the X direction of the slope G, the shock absorber energy is continuously absorbed by the deformation resistance force of the protective net 23 and the strength of the column 10.

As described above, in the present invention, since the action time of the load on the support column 10 is extended for a long time due to the sliding displacement of the support column 10 at the time of receiving, all of the impact F is instantaneously applied to the adjacent support columns 10 and 10. It can avoid acting.
An increase in the action time of the load means that an impact force is slowly applied to the support column 10.
Therefore, not only can the shock absorbing performance inherent to the column 10 be sufficiently exhibited, but also the shock absorbing performance can be sufficiently exerted on the protective net 23.
In other words, stress concentration on the lower portion of the support column 10 can be alleviated, and sudden bending of the base portion of the support column 10 can be suppressed.

<3> Propagation Action to Adjacent Span When a collapsing object collides with a part of the protection net 23, the protection net 23 located in the receiving range is bent and deformed toward the valley side, and due to the bending deformation resistance of the protection net 20, Absorbs impact energy.
When the deformation amount of the protection net 23 increases, when the adjacent support pillars 10 and 10 are displaced in the approaching direction, they are propagated to the support pillars 10 outside the figure through the protection net 23 located on the outer side and sequentially drawn.
Therefore, it functions to absorb impact energy even in a span that is not hit.

[Example 2]
In the following, other embodiments will be described. In the description, the same parts as those in the above-described embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted.

With reference to FIG. 7, an embodiment in which the lower portion of the support column 10 is slidably installed along the Y direction of the inclined surface G will be described.
In this embodiment, the ground plate 30 is provided with a plurality of slide holes 33 along the Y direction of the slope G. The plurality of slide holes 33 are in a parallel relationship with each other as in the first embodiment.
The fixing of the ground plate 30 via the ground plate anchor 42 is the same as in the first embodiment.

  In the present embodiment, the lower portion of the column 10 can slide along the Y direction of the inclined surface G together with the pressing plate 30 at the time of receiving, and the slide displacement of the column 10 at the time of receiving is the same as in the first embodiment. As a result, the concentration of stress on the lower part of the support column 10 can be alleviated, and the shock absorbing performance inherent to the protective fence can be sufficiently exhibited.

[Example 3]
With reference to FIG. 8, an embodiment will be described in which the lower portion of the support column 10 is slidable along the oblique direction of the slope G.
In the present embodiment, the ground plate 30 is provided with a plurality of slide holes 33 along the oblique direction of the slope G.

  In the present embodiment, the lower portion of the support column 10 can slide along the oblique direction of the inclined surface G together with the pressing plate 30 at the time of receiving. By accompanying the slide displacement, the stress concentration on the lower part of the column 10 can be relaxed, and the shock absorbing performance inherent in the protective fence can be sufficiently exhibited.

10 ... post 11 ... stop pin 21 ... rope net 21a, 21b ... horizontal rope material 22 ... wire net 23 ... protection net 24 ... interval holding rope 30 ... contact Base plate 31 ... outer cylinder 32 ... rubber plate 33 ... slide hole 34 ... reinforcing rib 35 ... hanging hook 40 ... mountain side anchor 41 ... side anchor 42 ... ground plate Anchor 43 ... Nut 45 ... Mountain side retaining rope 46 ... Mountain side positioning rope 47 ... Side retaining rope 48 ... Side positioning rope 50 ... Tensile material 51 ... Tightening bolt 52 ... This plate 53 ... Spring 54 ... Clamping nut

Claims (8)

A plurality of struts erected at intervals and a protective net stretched between the struts, the lower part of the strut is a protective fence erected on the slope via a ground plate,
The lower part of the column is erected so as to be slidable in the specific direction of the slope together with the ground plate,
Standing structure of the pillar in the protective fence.   The ground plate has a plurality of slide holes, and the ground plate is slidably fixed to the same number of ground plate anchors as the slide holes through the plurality of slide holes. The upright structure of the support | pillar in the guard fence of 1.   The support structure for a guard fence according to claim 2, wherein the plurality of slide holes are parallel to each other and are formed along an inclination direction of the slope.   The support structure for a guard fence according to claim 2, wherein the plurality of slide holes are parallel to each other and are formed along a direction orthogonal to the inclined direction of the inclined surface.   The support structure for a guard fence according to claim 2, wherein the plurality of slide holes are parallel to each other and are formed along an oblique direction of the slope.   The upright structure for a support post in a protective fence according to claim 1, wherein the support post and the ground plate are assembled.   2. The upright structure of a support post in a protective fence according to claim 1, wherein the support post and the grounding plate are integrally assembled in advance.   2. The upright structure for supporting columns in the protective fence according to claim 1, wherein the protective net is attached between adjacent columns in a span unit.

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