JP3413571B2 - Shock absorbing protective fence and shock absorbing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorbing protective fence and a shock absorbing method applicable as an overrun suppressing facility for large-sized fallen objects, automobiles, railways, airplanes and the like.

[0002]

2. Description of the Related Art Rigid columns are erected at predetermined intervals on slopes, and the upper and lower edges of a rope-made protective net are fixed and stretched between the columns to stretch the protective net and the rigidity of the column. Rockfall protection fences that receive rockfalls are well known.

Further, a plurality of shock absorbers are attached to a rigid column, and a plurality of horizontal rope members are gripped by the shock absorbers so as to be horizontally mounted.
A rock fall protection fence that attenuates impact energy by sliding frictional resistance between the horizontal rope material and the shock absorber has also been proposed.

Also, a net formed by rolling a rope material into a circle and fixing both ends of the rope material to form a ring body, and contacting the inner circumferences of the ring body with each other to form a chain is disclosed in JP-A-10-885.
No. 27 publication.

[0005]

<B> A conventional rockfall protection fence has a low kinetic energy of up to about 1500 kJ that can receive rockfall, and a construction method capable of handling more kinetic energy has not yet been proposed. . Particularly in Japan, where the land area is small, roads and railways constructed in mountainous areas are at risk of rockfalls, and there is a strong demand for the development of new technology that can prevent large-scale rockfall accidents.

<B> In the conventional rockfall protection fence, the impact energy of rockfall is absorbed by the net stretched between the columns, and the columns themselves are not expected to absorb energy. Therefore, if the rockfall collides directly with the support pillar, the original damping performance of the rockfall protection fence cannot be exhibited, and the support pillar is a weak point of strength of the rockfall protection fence.

The present invention has been made in view of the above points,
It is an object of the present invention to provide a shock absorbing technique capable of significantly improving the damping effect of shock energy and stopping an object having a kinetic energy of 4000 kJ or more.

[0008]

The invention according to claim 1 is
In a shock absorption protection fence in which columns are erected at a predetermined interval and a net is stretched around the columns, a net or an external force acting on the columns is acted as a compressive force in the axial direction of the columns. A resistor that attaches only the upper edge of the upper part to the upper part of the pillar and allows the lower part of the net to move when the external force in the net penetrating direction above a certain level acts on the lower part of the net separated from the pillar, and attenuates the external force. It is a shock-absorbing protective fence characterized by being connected to. In the invention according to claim 2, the columns are erected at a predetermined interval,
In a shock absorption protective fence in which a net is stretched between the struts, only the upper edge of the net is attached to the upper part of the struts so that an external force acting on the struts or the struts acts as a compressive force in the axial direction of the struts, A lower support rope is engaged with a lower edge portion of the net separated from the column, and when an external force in a net penetrating direction above a certain level acts on the lower support rope, the lower portion of the net is allowed to move and the external force is applied. It is a shock absorption protective fence, which is characterized by connecting a damping resistor. The invention according to claim 3 is claim 1 or claim 2.
In the shock-absorbing protective fence described in (1), the resistor engages with the damping rope arranged in the net crossing direction and the lower part of the net, and when it is gripped on the damping rope and an external force above a certain level acts, it slides. It is a shock absorption protection fence, which is characterized by comprising a shock absorber. The invention according to claim 4 is
The impact absorption protection fence according to any one of claims 1 to 3, wherein the support pillar is an elastic support pillar. The invention according to claim 5 is the invention according to claim 4.
The impact absorption protection fence described in (1) above is characterized in that both ends of an elastic column bent in an inverted U shape are erected with the both ends grounded to the ground. The invention according to claim 6 is the shock absorption protection fence according to any one of claims 1 to 3, wherein the support pillar is a rigid support pillar. According to a seventh aspect of the present invention, in the impact absorption protection fence according to any of the first to sixth aspects, the overlapping portion of the rope material in which the net is formed into a loop shape is held by a cushioning tool and chained in vertical and horizontal directions. A shock absorber, characterized in that the rope material slides and the loop diameter of the single wheel changes when a force greater than the gripping force of the shock absorber is applied. It is a protective fence. The invention according to claim 8 is,
In the shock absorption protection fence according to any one of 4, 6, 7
Shock absorption protection, characterized in that a restraint rope extending from the ground surface is connected to the upper part of the pillar to suppress tilting, and a cushioning device that slides when a certain amount of tension acts in the middle of the restraint rope is interposed. It is a fence. The invention according to claim 9, in the impact absorbing safety barriers according to claim 2 or claim 7, is attached to the supporting rope between supporting pillars, a bumper is provided at the edge of the nets, the bumper and A shock absorbing protection fence is slidably fitted to the support rope. According to a tenth aspect of the present invention, there is provided a method in which a net is stretched between columns that are erected at a predetermined interval and the impact is absorbed by the rigidity of the columns and the deforming force of the net. Using the shock absorbing protection fence according to any one of the above, while making the external force in the penetrating direction of the net act as a compressive force in the axial direction of the elastic strut, the external force is attenuated by the movement resistance of the lower part of the net by the resistor. Yes, it is a shock absorption method.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1 of the present invention will be described below with reference to the drawings.

(B) Basic structure of shock absorption protection fence FIG. 1 is a perspective view showing an outline of the shock absorption protection fence, and FIG.
The cross-sectional view is shown in FIG. The shock absorption protection fence is composed of a plurality of elastic columns 20 standing upright on the slope 10 at predetermined intervals and a loop net 30.

The upper edge of the loop net 30 is formed by each elastic column 2.
While being attached to the upper part of 0, the lower edge of the loop net 30 is attached to the ground surface via a resistor. The resistor may be a mechanism that resists an external force that the loop net 30 tries to move to the valley side.

That is, the upper edge of the loop net 30 is
It is attached between the upper parts of the elastic columns 20 via the upper support ropes 40 slidably engaged.

A lower support rope 41 is slidably engaged with the lower edge of the loop net 30. The lower support rope 41 is provided in the inclined direction of the slope 10 (the lower support rope 4
It is supported by a damping rope 50 and a shock absorber 51 attached along the direction 1).

In the present example, "engagement" means a state in which the rope members can mutually transmit force regardless of whether or not the rope members are wound around. Each part will be described in detail below.

(B) Elastic support The elastic support 20 is a column having both rigidity and elasticity.
A large number of elastic wire rods made of steel or resin, which are hard to be plastically deformed, are arranged side by side to form a tubular or columnar shape, or a tubular body formed by coiling spring steel is included. The point is that the strut 20 is elastically deformed over its entire length when a force exceeding the compressive strength of the strut 20 is applied, and the impact energy can be attenuated.

Anchors 11, 11, 12 are provided at three points on the slope so as to surround each elastic column 20. The elastic column 20 is supported by the two mountain side retaining ropes 60, 60 and the single valley side retaining rope 61 connected between the anchors 11, 11, 12 and the upper portion of the elastic column 20. It is desirable that the elastic support columns 20 stand upright on the slope 10.

In this example, in the middle of each mountain side restraint rope 60,
The case where a known shock absorber 62 that attenuates energy by sliding friction resistance is interposed is shown, but the shock absorber 62 is not an essential element.

FIG. 3 is a perspective view of an upper portion of the elastic column 20 in which the loop net 30 is omitted. A plurality of brackets 22 are provided on the peripheral surface of the head cap 21, and shackles 23 attached to these brackets 22 are used. The upper portions of the retaining ropes 60 and 61 are connected to each other. Reference numeral 24 in the drawing is a bracket through which the upper support rope 40 is inserted.

(C) Loop Net The loop net 30 is a net having a shock absorbing action, which is formed by combining a rope material made of wire rope, PC steel wire, PC steel stranded wire, carbon fiber, aramid fiber, etc. and the shock absorber 70. Only the upper edge of the elastic column 20 is attached to the elastic column 20. This is to convert the impact force into the axial compression force of the elastic column 20.

Referring to FIG. 4, the loop net 30 will be described.
Is composed of a plurality of continuous wheel elements 31a, 31b, 31c ... And a plurality of shock absorbers 70, and adjacent continuous wheel elements 31a, 31b, 31c ... Are engaged with each other.

[Continuous Wheel Element] The continuous wheel element 31a is composed of a continuous body of a plurality of single wheels 32a, 32a ... Each rope material is knitted into a continuous loop shape (or a spiral expanded shape). Other continuous wheel elements 31b, 31c ...
Similarly, a plurality of single wheels 32, 32b ... 32c, 32c ...
It is composed of

[Single Wheel] Each single wheel 32a, 32b, 32
The c ... are engaged with each other to provide continuity in the vertical and horizontal directions, and when an external force such as a tensile force acts, each single wheel 32
The inner diameters of a, 32b, 32c ... Change. In the present example, a case is shown in which the individual single units 32a, 32b, 32c ... Are wound and engaged, but they may be connected and engaged by a shock absorber without being wound.

An upper support rope 40 (not shown) is slidably engaged with the plurality of single wheels 32a, 32a, ... Which constitute the uppermost continuous wheel element 31a, and similarly, although not shown, the lowermost one. A lower support rope 41 (not shown) is slidably engaged with the plurality of single wheels 32n, 32n ... Constituting the position continuous wheel element 31n.

The orientation of the loop net 30 is not limited to the orientation shown in FIG. 4. For example, the loop net 30 may be turned upside down or rotated at an appropriate angle such as 90 degrees or 45 degrees. May be

[Cushioning tool] The cushioning tool 70 is gripped from the both sides at the intersection of the rope material, and when the excessive external force (tensile force) exceeding the set gripping force (sliding friction resistance) acts on the rope material, It has a structure that generates sliding resistance between them, and at least one is attached to each single wheel 32a, 32b, 32c. Although not shown, the shock absorber 70 may be additionally provided at the adjoining portion (intersection portion) of the single wheels 32a, 32b, 32c, ... Adjacent in the vertical and horizontal directions.

Referring to FIG. 5, the shock absorber 70 comprises an intermediate plate 71, two outer plates 72, 72, a fastening bolt 73 and a nut 74.

In the facing surfaces of the intermediate plate 71 and the outer plates 72, 72, a receiving groove 75 having a semicircular cross section capable of receiving and sandwiching the rope members of the individual wheels 32c, (32a, 32b ...) Intersecting.
Are respectively recessed, and the gripping force of the rope material can be adjusted by fastening the fastening bolts 73 and the nuts 74.

The above-mentioned cushioning tool 70 is an example, and in addition, a jig having a structure in which two portions of the rope material are sandwiched between three plate bodies and clamped by bolts and nuts, a known wire clip, etc. Can be used

(D) Resistor at the bottom of the net [attenuation rope] The damping rope 50 is a rope material for setting the slidable length of the shock absorber 51, and is provided between the anchors 11 and 12 which also serve as the retaining rope. , Which are arranged in a substantially V-shaped plane.

The damping rope 50 may be arranged obliquely with respect to the inclination direction of the slope 10, and may be parallel to the inclination direction, and the arrangement position thereof is not limited to the vicinity of the elastic column 20, and the lower portion thereof may be arranged in the lower portion. It may be at any position intersecting with the support rope 41, and the number of the provided ropes should be appropriately selected according to the site.

[Cushioning Tool] As shown in FIG. 6, for example, the cushioning tool 51 includes two sandwiching plates 52 and 53 and a bolt / nut 54.
The damping rope 50 is accommodated in the accommodation groove 55 having a semicircular cross section formed on the opposing surfaces of the two plates 52 and 53, and is held by the bolts and nuts 54.
The lower support rope 41 is attached to the guide portion 56 formed integrally with
It is structured so that it can be inserted movably. Shock absorber 51
Generates sliding resistance with the lower support rope 41 when an excessive external force (tensile force) exceeding the set gripping force (sliding friction resistance) is applied.

[0032]

[Function] Next, the shock damping function will be described. (A) Damping element shock absorption When a shock such as a rock fall acts on the protective fence, the kinetic energy is damped by the damping effect of a plurality of damping elements (loop net 30, resistor under the net, elastic support 20) described below. At the same time, the loop net 30 is deformed so as to wrap it and receives rockfalls and the like. For the sake of convenience, each damping action will be described individually, but in practice they act in parallel.

(B) Damping action of loop net The impact acting on a part of the loop net 30 is dispersed over the entire net, and is first damped by the deformation of the entire net.
Further, the impact energy is attenuated by the deformation resistance force of the rope material when the group of the single wheels 23a, 32b, 32c constituting the loop net 30 shown in FIG. 2 is deformed from a circular shape to a non-circular shape such as a quadrangle.

Further, the impact energy is determined by the individual wheels 32a,
When the rope material slides and the individual wheels 32a, 32b, 32c are reduced in diameter, the rope material acts as a tensile force on each of the rope members constituting 32b, 32c and exceeds the gripping force of the shock absorber 70. , Impact energy is attenuated. As the rope members slide, the net surface of the loop net 30 deforms toward the downstream side of the slope 10 so as to wrap rock fall or the like.

In a general net, the hitting point is open and rockfalls and the like tend to pass through easily. However, in the case of the loop net 30, the hitting point is reduced in diameter, so rockfalls and the like are difficult to pass through. As described above, the impact energy acting on the loop net 30 is efficiently and promptly attenuated by the plurality of damping actions in the entire net.

(C) Damping action by the resistor at the bottom of the loop net The impact energy acting on the loop net 30 is transmitted to the shock absorber 51 engaging with the lower support rope 41 as a pushing force toward the valley side of the slope 10. It This pushing force is the shock absorber 5.
When the sliding resistance between 1 and the damping rope 50 is exceeded, the shock absorber 51 starts sliding on the damping rope 50 as shown in FIG. 7, and the impact energy is attenuated during this sliding.

(D) Damping action of the elastic column The elastic column 20 is directly or via the loop net 30.
When a shock is applied to, a part of the shock energy is attenuated by the rigidity of the elastic column 20.

Only the upper portion of the loop net 30 has the elastic support 2
Since it is connected to the upper part of 0, the impact energy acts only on the elastic column 20 as a compressive force in its axial direction, and does not act as a large bending force.

When this compressive force exceeds the strength of the elastic support column 20, as shown in FIG. 7, the intermediate part of the elastic support column 20 is elastically deformed integrally or while the elastic wire group is scattered, and the impact energy is attenuated during this deformation. To be done.

When a shock absorber 62 is provided on the restraining rope 60, the shock energy is attenuated by the sliding resistance of the shock absorber 62.

Due to the composite damping action of the plurality of damping elements described above, the rockfall finally becomes the loop net 30.
Be accepted by. When the rock fall is lightweight or after the rock fall is removed, the elastic column 20 is restored to its original shape by the self-elastic force.

[0042]

Second Embodiment In the following description, the same parts as those in the above-described embodiments are designated by the same reference numerals, and detailed description of the structure and operation will be omitted.

FIG. 8 shows another embodiment in which the elastic column 20 is bent in a U shape and both ends thereof are fixed to the slope 10.

In this example, as in the first embodiment, the upper edge portion of the loop net 30 is attached to the upper portion of the upright portion of the elastic column 20 through the upper support rope 40, and the lower edge portion is provided at the lower edge portion. The rope 41 is attached to a shock absorber 51 which is held by a damping rope 50 on the ground side.

The basic damping element and the damping action according to the present example are the same as those of the first embodiment described above, but since the total length of the elastic column 20 that contributes to the damping of impact energy can be set long in this example, the elasticity is reduced. There is an advantage that the damping performance using the elasticity of the column 20 is significantly improved. Furthermore, by connecting the way of the damping rope 50 connected between the anchors 11 and 12 to the lower part of the elastic column 20 bent in an inverted U shape, the supporting force of the damping rope 50 can be set large and the anchors 11, 12 has the advantage that the design resistance can be reduced.

[0046]

Third Embodiment of the Invention FIG. 9 shows another loop net 30. This example is a net formed by inscribed in a plurality of single wheels 33 that can be expanded in diameter and chained in the vertical and horizontal directions. Each independent single wheel 33 is a shock absorber 70 for the overlapping portion of the rope material formed in a loop shape. A rope member formed by gripping and extending from the shock absorber 70 is formed as the extra length portion 34 that allows sliding. Reference numeral 35 is a stopper that restricts the rope material from coming out. In this example, when the single wheel 33 is expanded in diameter, sliding resistance is generated between the rope member and the shock absorber 70, but the other damping elements are the same as those in the first embodiment described above.

Further, various kinds of publicly known protective nets may be applied instead of the loop net 30 and the elastic post 20 may be provided on condition that the upper part of the net is attached to the upper part of the post and the resistor is provided on the lower part of the net. It is also possible to apply a known rigid column instead of the above.

[0048]

Fourth Embodiment As shown in FIG. 10, a shock absorber 80 is provided in the middle of the rope on one or both of the upper support rope 40 and the lower support rope 41 to exceed the set gripping force of the shock absorber. When tension is applied, the support rope 4
The damping performance of the shock absorbing protection fence is further improved by sliding the dampers between 0 and 41 and the cushioning tool 80 so as to reduce the damping.

Further, a cushioning tool (not shown) may be provided between the support ropes 40 and 41 and the upper and lower edges of the loop net 30.

A cushioning tool may be attached to the elastic column 20 so that the elastic rope 20 is damped between the support ropes 40 and 41.

The loop net 30 includes a support rope 40,
Instead of using 41, the elastic column 20 may be directly fixed.

Instead of the elastic columns 20, rigid columns may be applied.

[0053]

Fifth Embodiment of the Invention FIG. 11 shows another shock absorbing protection fence. In this example, the upper support rope 40 is fixed to the elastic column 20 via the support member 25, and the fitting arm 75 is integrally formed with the shock absorber 70 provided on the uppermost edge of the loop net 30. The opening 76 of the upper support rope 4
It shows the case where it is slidably fitted to 0. The fitting structure is not limited to the illustrated form, and the essential point is that the opening 76 of the fitting arm 75 is fitted so as to allow sliding in the rope longitudinal direction without coming off from the rope 40. Good.

In this example, since the loop net 30 slides over the span between the elastic struts 20 at the time of receiving an impact, a larger impact energy can be attenuated. Although not shown, the lower support rope 41 may be slidably fitted to the elastic column 20 as well. .

[0055]

The present invention can obtain the following effects. (A) By attaching the upper part of the net to the upper part of the column and providing a resistor on the lower part of the net, the damping action of converting the shock into an axial compressive force on the column and the damping action of the resistor on the lower part of the net When used together, impact energy can be efficiently attenuated. (B) When the elastic column and the loop net are combined, the impact energy damping effect is significantly improved, and 4000 kJ
An object having the above kinetic energy can be slowly wrapped and stopped. (C) It can be used not only as a protective fence for huge rockfalls but also as an emergency stop fence for overrun aircraft, trains, or automobiles. (D) The stanchion may be either a rigid type or an elastic type, and the net may be either a loop net or a known protective net, and it is possible to combine them according to the situation at the site and the potential energy to be attenuated.

[Brief description of drawings]

FIG. 1 is a perspective view of a shock absorption protection fence according to the present invention.

[Figure 2] Vertical cross-sectional view of shock absorption protection fence

FIG. 3 is a perspective view of the upper part of the elastic column.

FIG. 4 is a front view of the loop net.

5 is a cross-sectional view of VV of FIG.

FIG. 6 is a perspective view of a resistor under the loop net.

FIG. 7 is an explanatory diagram of a damping action.

FIG. 8 is a cross-sectional view of a shock absorption protection fence according to another embodiment using inverted U-shaped elastic columns.

FIG. 9 is a front view of a loop net according to another embodiment.

FIG. 10 is a front view of another shock absorption protection fence in which a support rope is provided with a shock absorber.

FIG. 11 is a cross-sectional view of the upper part of another shock absorbing protection fence in which a shock absorber is slidably fitted to a support rope.

[Explanation of symbols]

10 slopes 11,12 anchor 20 elastic columns 23 Shock absorber 30 loop net 40 Upper support rope 41 Lower support rope 50 damping rope 51,70 shock absorber 60,61 Restraint rope

─────────────────────────────────────────────────── ─── Continuation of the front page (73) Patent holder 596183125 Civil Engineering Co., Ltd. Niigata City Toriyano 3-14-13 (72) Inventor Hiroshi Yoshida 561 Mizushima, Oyabe City, Toyama Prefecture (56) Reference Japanese Patent Laid-Open No. 7- 42117 (JP, A) JP 10-88527 (JP, A) JP 6-173221 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) E01F 7/04 F16F 7 / 00-7/14

Claims (10)

(57) [Claims] 1. In a shock absorption protection fence in which columns are erected at a predetermined interval and a net is stretched between the columns, an external force acting on the net or the columns acts as a compressive force in the axial direction of the column. As is the case, only the upper edge of the net is attached to the upper part of the strut, and if an external force in the net penetrating direction above a certain level acts on the lower part of the net separated from the strut, the lower part of the net is allowed to move to cause the external force. A shock-absorbing protective fence characterized by connecting a resistor that attenuates. 2. In a shock absorption protection fence in which columns are erected at a predetermined interval and a net is stretched between the columns, an external force acting on the net or the columns acts as a compressive force in the axial direction of the columns. As much as possible, only the upper edge of the net is attached to the upper part of the strut, the lower support rope is engaged with the lower edge of the net separated from the strut, and the net penetrates a certain amount or more in the middle of the lower support rope. A shock absorbing protection fence, characterized in that a resistor is connected to allow the movement of the lower part of the net when the external force in the direction acts and attenuate the external force. 3. The shock absorbing protection fence according to claim 1 or 2, wherein the resistor is engaged with a damping rope arranged in a direction intersecting with the net, and the lower part of the net is engaged.
A shock absorbing protection fence comprising a shock absorbing tool which is gripped on the damping rope and slides when an external force of a certain amount or more acts. 4. The shock absorption protection fence according to claim 1, wherein the support pillar is an elastic support pillar. 5. The shock absorption protection fence according to claim 4, wherein both ends of the elastic pillar bent in an inverted U shape are grounded to the ground. 6. The shock absorption protection fence according to claim 1, wherein the support pillar is a rigid support pillar. 7. The shock-absorbing protective fence according to claim 1, wherein the overlapping portion of the rope material having a net formed in a loop is gripped by a cushioning tool and chained in vertical and horizontal directions. A shock-absorbing protective fence, characterized in that the rope material slides when the force greater than the gripping force of the shock absorber acts, and the loop diameter of a single wheel changes, which is a loop net formed as an aggregate. 8. The shock-absorbing protection fence according to claim 1, 2, 3, 4, 6, 7, wherein a restraint rope extending from the ground surface is connected to the upper part of the pillar to suppress tilting and A shock-absorbing protection fence that is equipped with a shock absorber that slides when a certain amount of tension is applied midway along the rope. 9. The method of claim 2 or shock absorbing safety barriers according to claim 7, is attached to the supporting rope between supporting pillars, a bumper is provided at the edge of the nets, the support rope the bumper A shock absorption protection fence that is slidably fitted to the. 10. A method of absorbing a shock by the rigidity of the support and the deforming force of the support by stretching a net between the support erected upright at a predetermined interval. The impact absorption protection fence described above is used to allow the external force in the penetrating direction of the net to act as a compressive force in the axial direction of the elastic strut, while damping the external force by the movement resistance of the lower part of the net by the resistor. Absorption method.