JP2008138425A - Post for guardrail - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a post for a guardrail allowing a front face flange to be thin-walled while ensuring excellent impact absorbing ability. <P>SOLUTION: The post P for the guardrail has a pedestal 1 fixed to a foundation K constructed at the side of a road R, and a post body 2 erected on the pedestal 1. The post body 2 comprises the front face flange 21 facing the road R; a rear face flange 22 arranged behind the front face flange 21; and a web 23 connecting the front face flange 21 to the rear face flange 22. The front face flange 21 has a base 21a rising from the pedestal 1, and an inclined part 21b rising obliquely upward to the front side from the upper end of the base 21a. When a collision load is applied to the post body 2 from the road R side, the post body 2 tilts backward while linearly extending a bent part B1 formed of the base 21a and the inclined part 21b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a support fence post installed along a road.

  Known as a protective fence that prevents vehicles from escaping from the road, a horizontal beam (horizontal material) is spanned between a plurality of support columns (hereinafter referred to as "protection fence columns") that are erected at predetermined intervals. It has been.

  From the standpoint of preventing the departure of vehicles, etc., it is desirable to use a strong protective fence. However, if it is made stronger than necessary, there is a risk of damage to the driver and passengers due to the impact at the time of collision. Since a vehicle that touches or collides with the vehicle may be bounced back to the road side by the protective fence and cause a secondary disaster, the conventional protective fence is used when a certain amount of external force is applied due to the vehicle contacting or colliding. First, the collision energy is absorbed by crushing and bending deformation of the cross beam, and then the collision energy is absorbed by tilting or buckling of the protective fence post. With this configuration, it is possible to prevent the vehicle or the like from rebounding on the road side while minimizing damage to the driver or the passenger.

  By the way, as for the support | pillar for protection fences, what is equipped with the base fixed to the foundation constructed by the roadside, and the support | pillar main body of the cross-section H standing upright on this base, for example, patent document 1 and Patent Document 2, as shown in FIGS. 7 (a) and 7 (b), a curved recess D serving as a starting point of backward tilting is formed on the rear surface flange of the column main body, and the lower half of the column main body. There is disclosed a guard fence post having a neutral axis N of an S shape. The guard fence support disclosed in Patent Document 1 is made of cast aluminum alloy, and the guard fence support disclosed in Patent Document 2 is made of cast iron.

Japanese Patent Publication No.57-42764 Japanese Patent Laid-Open No. 11-336034

  In this type of protective fence support, the strut body is tilted backward to absorb the collision energy. However, when the support body has a general H-shaped cross section, the support body is When tilting, the front flange is subject to tensile deformation (elongation due to plastic deformation). Therefore, it is necessary to increase the thickness of the front flange so that the front flange does not break. However, when the thickness of the front flange is increased, there is a problem that the material cost increases and the weight of the guard fence post increases. In addition, the methods shown in Patent Document 1 and Patent Document 2 are limited in manufacturing method because of the complexity of the shape. Furthermore, in order to determine the optimum shape, a destructive test or the like is performed many times. There was a need to do. Also in this case, since the front flange is subject to tensile deformation, it is necessary to increase the thickness of the front flange so that the front flange does not break.

  From such a viewpoint, it is an object of the present invention to provide a protective fence post capable of reducing the thickness of the front flange while ensuring excellent shock absorption capability.

  The present invention, which was created to solve such a problem, is a support fence post having a pedestal fixed to a foundation constructed on the side of a road, and a support column body erected on the pedestal, The column main body includes a front flange facing the road, a rear flange disposed behind the front flange, and a web connecting the front flange and the rear flange. A base portion that rises from a pedestal and an inclined portion that rises diagonally upward from the upper end of the base portion, and is formed by the base portion and the inclined portion when a collision load is applied to the column main body from the road side. The prop main body tilts backward while the bent portion is straightly extended.

  According to this protective fence support, when the support main body tilts backward due to a collision load, the bent part formed by the base and the inclined part is stretched in a straight line, so that the front flange necessary for tilting the support main body As a result, a part of the amount of deformation (elongation) of the front flange is secured. Compared to the case where the deformation amount of the front flange necessary for tilting the column body is secured only by tensile deformation of the front flange, the thickness of the front flange is increased. The thickness can be reduced. In other words, according to this protective fence post, in addition to the tensile deformation of each part of the front flange, the bent part is extended in a straight line, ensuring the amount of deformation of the front flange necessary for tilting the post body, and as a result Since a sufficient amount of collision energy can be absorbed, even if the front flange is thin, it is possible to tilt the column body more than the conventional one without breaking the front flange.

  If the height difference between the upper surface of the pedestal and the bent portion exceeds 200 mm, the bending moment generated in the bent portion due to a collision load is reduced, and the bent portion is difficult to be straightened. The difference in height between the bent portion and the bent portion is preferably 200 mm or less. Further, if the height difference between the upper surface of the pedestal and the bent portion is less than 30 mm, the amount of deformation when the bent portion is extended cannot be obtained sufficiently, and the front flange cannot be thinned. The difference in height is preferably 30 mm or more.

  In the present invention, it is desirable to incline the base toward the rear flange side. That is, it is desirable that the base is raised from the pedestal toward the rear obliquely upward, and the inclined portion is raised from the upper end of the base toward the front obliquely upward. If it does in this way, since the web width | variety in the upper end part of a base will become small and the bending rigidity in this position will become small, a bending part will become easy to be extended linearly. In addition, since the lower part of the column main body is prevented from becoming thicker than necessary, it is possible to reduce the weight of the column for the protective fence, and thus it is possible to reduce the material cost.

  The front flange may be provided with a main part that rises obliquely upward from the upper end of the inclined part, and a bent part may be formed by the inclined part and the main part. In this way, when a collision load is applied to the column main body from the road side, the bent portion formed by the base portion and the inclined portion and the bent portion formed by the inclined portion and the main portion are stretched linearly. Since the column main body tilts rearward, it becomes possible to more easily secure the amount of deformation of the front flange necessary for tilting the column main body.

  In addition, when the front flange includes two bent portions, if the height difference between the two bent portions is smaller than 30 mm, the two bent portions are difficult to extend linearly, and if larger than 100 mm, Since the width of the web at the upper end of the inclined portion becomes large and the bending rigidity at this position becomes too high, and the upper bent portion is hardly stretched linearly, the height difference between the two bent portions is 30 mm. It is desirable that it is 100 mm or less.

  It is desirable that the rear flange has a band plate shape without bending. If it does in this way, the appearance of the support fence post will be clean.

  When the angle formed between the plane parallel to the rear flange and the inclined portion is less than 5 degrees, the amount of deformation of the front flange secured by extending the bent portion linearly decreases, and 30 If the angle exceeds the degree, the width of the web at the upper end of the inclined portion becomes large and the bending rigidity at this position becomes too high, and the upper bent portion becomes difficult to be straightened. The angle formed by the surface and the inclined portion is preferably 5 degrees or more and 30 degrees or less.

  According to the protective fence support according to the present invention, it is possible to reduce the thickness of the front flange while securing an excellent shock absorption capability.

  FIG. 1 is a perspective view showing a vehicular protective fence G provided with a protective fence column P according to the present embodiment. As shown in the figure, the vehicle guard fence G includes three horizontal beams H installed along the road R, and a plurality of guard fence posts P, P,... That support the horizontal beams H. Yes. In each member, a surface facing the road R is a “front surface”, and a surface on the opposite side (road shoulder side) is a “rear surface”.

  The three horizontal beams H are arranged in parallel to each other. In addition, in this embodiment, although the guard fence G for vehicles provided with the three horizontal beams H is illustrated, it is not the meaning which limits the number of horizontal beams.

  The horizontal beam H includes a plurality of hollow beam members H1, H1,... Arranged in the longitudinal direction, and a connecting member H2 arranged inside the boundary portion between the adjacent hollow beam members H1, H1. Yes. The hollow beam material H1 is a cylindrical shape, and is cut to the same length as the interval between the adjacent protective fence posts P, P. The connecting member H2 is made of a hollow material inserted into the hollow beam material H1, and is disposed so as to straddle the boundary portion between the adjacent hollow beam materials H1, H1.

  In the present embodiment, the case where the cross section of the cross beam H is circular has been illustrated, but the present invention is not limited to this. For example, an oval shape, a bullet shape, a rectangular shape, or the like may be used.

  As shown in FIG. 2, the protective fence column P includes a pedestal 1 fixed to a reinforced concrete foundation K constructed on the side of the road R, and a column body 2 erected on the pedestal 1.

  The base 1 is made of a steel plate having a rectangular shape when viewed from above, and has bolt insertion holes 1a at positions corresponding to the nuts N1 embedded in the foundation K. A bolt B1 screwed into the nut N1 is inserted through the bolt insertion hole 1a. In the present embodiment, the bolt insertion holes 1a are formed at two positions on both sides of the web 23 to be described later. However, the number of bolt insertion holes 1a is not limited. Note that the pedestal 1 is not limited to a rectangular shape and is not shown, but may be a polygonal shape or a circular shape.

  The column main body 2 shown in FIG. 2 includes a front flange 21 facing the road R, a rear flange 22 disposed behind the front flange 21, and a web 23 connecting the front flange 21 and the rear flange 22. In addition, in the present embodiment, a mounting portion 24 formed from the upper end of the front flange 21 to the upper end of the rear flange 22 is provided.

  The front flange 21 includes a base portion 21a that rises from the base 1, an inclined portion 21b that rises from the upper end of the base portion 21a, and a main body portion 21c that rises from the upper end of the inclined portion 21b. It is bent at the boundary portion with the portion 21b, and in the present embodiment, it is further bent at the boundary portion between the inclined portion 21b and the main portion 21c. The front flange 21 is made of a bent steel plate and is fixed to the front end portion of the base 1 and the front edge portion of the web 23 by welding. As shown in FIG. 3 (a), the width dimension of the front flange 21 gradually decreases as it goes upward. As shown in FIG. 3 (b), the thickness of the front flange 21 increases from the lower end. Constant up to the top.

  In the following description, the bent portion C1 formed by the base portion 21a and the inclined portion 21b is referred to as the lower bent portion C1, and the bent portion C2 formed by the inclined portion 21b and the main portion 21c is the upper bent portion. It will be referred to as C2.

As shown in FIG. 3A, the base 21a has a flat plate shape (see FIG. 2), but its width dimension gradually decreases as it goes upward, and the shape seen from the front is substantially trapezoidal. Presents. As shown in FIG. 3B, the base 21a is inclined toward the rear flange 22 side. In the present embodiment, a flat plate-like portion located above the pedestal 1 in the base portion 21a rises straight toward the rear obliquely upward. When the base portion 21a is tilted toward the rear flange 22 side, the width of the web 23 at the upper end portion (lower bent portion C1) of the base portion 21a is reduced, and as a result, the bending rigidity at the lower bent portion C1 is reduced. As shown in FIG. 4, the inclination angle θ ₁ of the base 21a with respect to the plane V perpendicular to the upper surface of the pedestal 1 is set to 20 degrees or less, and the height difference between the upper surface of the pedestal 1 and the upper end of the base 21a (ie, The height difference between the upper surface of the base 1 and the lower bent portion C1) h ₁ is set to 200 mm or less. In addition, although illustration is abbreviate | omitted, you may stand up so that the base 21a may become perpendicular | vertical with respect to the upper surface of the base 1 (namely, (theta) ₁ = 0). Incidentally, the height difference h ₁ is smaller than 30 mm, there is a possibility that the amount of deformation of the front flange 21 when deformed as the lower bent portion C1 becomes straight (elongation amount) decreases, the height difference h ₁ Is preferably 30 mm or more.

As shown in FIG. 3A, the inclined portion 21b has a flat plate shape (see FIG. 2), and its width dimension gradually decreases as it goes upward, and the shape seen from the front is substantially trapezoidal. Presents. As shown in FIG. 3B, the inclined portion 21b rises from the upper end of the base portion 21a toward the front obliquely upward, and forms a lower bent portion C1 that protrudes rearward together with the base portion 21a. In addition, the upper end (namely, upper side bending part C2) of the inclination part 21 is located below the horizontal beam H of the lower stage. As shown in FIG. 4, the angle θ ₂ formed by the plane W parallel to the rear flange 22 and the inclined portion 21b is set to 5 degrees or more and 30 degrees or less, and the height difference between the lower end and the upper end of the inclined section 21b ( in other words, the height difference) _{h 2} of the lower bent portion C1 and the upper bent portion C2 is set to be 30mm or 100mm or less.

As shown in FIG. 3A, the main body portion 21c has a flat plate shape (see FIG. 2), but its width dimension gradually decreases toward the top, and the shape seen from the front is substantially trapezoidal. Presents. Insertion holes 211 and 212 are formed in the main body portion 21c. The upper insertion holes 211 are formed on both sides of the web 23 at the installation height of the middle horizontal beam H (see FIG. 3B). A fixing bolt B3 (see FIG. 3B) for fixing the middle horizontal beam H is inserted through the insertion hole 211. Further, the lower insertion holes 212 are formed on both sides of the web 23 at the installation height of the lowermost horizontal beam H (see FIG. 3B). A fixing bolt B4 (see FIG. 3B) for fixing the lowermost horizontal beam H is inserted through the insertion hole 212. As shown in FIG. 3B, the main body portion 21c rises from the upper end of the inclined portion 21b toward the rear obliquely upward, and forms an upper bent portion C2 that protrudes forward with the inclined portion 21b. . As shown in FIG. 4, the inclination angle theta ₃ of the main part 21c with respect to a plane perpendicular V to the upper surface of the base 1 is 20 degrees or less, and is smaller than the inclination angle theta ₁ of the base 21a. In addition, although illustration is abbreviate | omitted, you may stand up the main-body part 21c so that it may become perpendicular | vertical (namely, (theta) ₃ = 0) with respect to the upper surface of the base 1. FIG.

As shown in FIGS. 3 (b) and 3 (c), the rear flange 22 is made of a steel member having a strip-like shape without bending, and in a state where the rear flange 22 is erected on the upper surface of the base 1, 1 and the rear edge of the web 23. The width dimension of the rear flange 22 is constant from the lower end to the upper end, but is narrower than the front flange 21. Further, the thickness of the rear flange 22 is constant from the lower end to the upper end, but is thicker than the front flange 21. The rear flange 22 rises from the upper surface of the pedestal 1 toward the front obliquely upward. The inclination angle θ ₄ of the rear flange 22 with respect to the plane V perpendicular to the upper surface of the pedestal 1 is 5 degrees or less. Although illustration is omitted, the rear flange 22 may be raised so as to be perpendicular to the upper surface of the base 1.

  The web 23 stands from the upper surface of the base 1. The web 23 is located on a vertical plane including the center line in the width direction of the front flange 21 and the center line in the width direction of the rear flange 22. As shown in FIG. 3B, the corners 23 a and 23 a at the lower end of the web 23 are applied to the joint between the base 1 and the front flange 21 and the joint between the base 1 and the rear flange 22. It is cut out in a fan shape so that fillet weld beads can be avoided.

  The mounting portion 24 is made of a steel member having a mounting seat 24 a formed in a cylindrical surface shape along the outer surface of the uppermost horizontal beam H, and is attached to the upper end portions of the front flange 21, the rear flange 22 and the web 23. It is fixed by welding. As shown in FIG. 3A, insertion holes 241 are formed on both sides of the mounting seat 24a with the web 23 interposed therebetween. A fixing bolt B <b> 2 (see FIG. 3B) for fixing the upper horizontal beam H is inserted through the insertion hole 241.

  As shown in FIG. 2, in order to install the protective fence support P on the upper surface of the foundation K, the bolt insertion holes 1a, 1a,... Of the base 1 are positioned directly above the nuts N1, N1,. The pedestal 1 is placed on the upper surface of the foundation K so that the bolt B1 is inserted into the bolt insertion hole 1a of the pedestal 1 and the shaft portion is screwed into the nut N1.

  Further, as shown in FIG. 3B, in order to fix the uppermost horizontal beam H to the protective fence support P, the boundary portion of the hollow beam members H1 and H1 (see FIG. 1) (that is, the connecting member H2). It is only necessary to hold the portion where is disposed) on the mounting portion 24 of the column main body 2. Specifically, while the rear portion of the horizontal beam H is brought into contact with the mounting seat 24a of the mounting portion 24, the insertion hole 241 (see FIG. 3A) of the mounting seat 24a and the insertion hole (not shown) of the hollow beam member H1. ) Is inserted through the shaft portion of the bolt B2 and the tip portion thereof is screwed into a female screw hole (not shown) formed in the connecting member H2.

  Further, in order to fix the middle horizontal beam H to the protective fence support P, the boundary portion of the hollow beam members H1 and H1 is positioned in front of the insertion hole 211 (see FIG. 3A) of the front flange 21. The spacer 25 (see FIG. 2) is interposed between the horizontal beam H and the front flange 21, the insertion hole 211 of the front flange 21, the insertion hole (not shown) of the spacer 25, and the insertion hole (not shown) of the hollow beam material H1. ) Is inserted through the shaft portion of the bolt B3, and the tip portion thereof is screwed into a female screw hole (not shown) of the connecting member H2. The same applies to the case where the lowermost horizontal beam H is fixed to the protective fence support P.

  When a collision load is applied to the protective fence post P configured as described above from the road R side, the lower bent portion C1 and the upper bent portion C2 are linearly formed as shown in FIG. As shown in FIG. 5 (b), the column main body 2 tilts backward while being stretched, and finally the rear flange 22 falls down and buckles, and the web 23 sits in the out-of-plane direction. Bow. While the lower bent portion C1 and the upper bent portion C2 are linearly stretched, the column main body 2 tilts backward, so that the impact applied to the vehicle is alleviated, and the rear flange 22 and the web 23 are buckled. Thus, the front flange 21 is prevented from being broken and the impact applied to the vehicle is reduced.

  As described above, according to the protective fence support P, the collision energy is absorbed by the deformation resistance when the support main body 2 is tilted rearward due to the collision load, but it does not depend on the tensile deformation of the front flange 21 itself. Since the lower bent portion C1 and the upper bent portion C2 are linearly extended, a deformation amount (elongation amount) necessary for tilting the column main body 2 is ensured, so that the front flange 21 is broken. However, the collision energy is absorbed in combination with the deformation of the web 23 and the like. That is, it is difficult to exceed the limit of the amount of tensile deformation compared to the case where the amount of deformation of the front flange 21 necessary for tilting the column main body 2 is ensured only by the tensile deformation (elongation) of the front flange 21, so A predetermined tilt amount can be obtained without using a material or a complicated shape, and as a result, a necessary amount of collision energy absorption can be ensured. That is, according to this protective fence support P, in addition to the tensile deformation of each part of the front flange 21, the lower bent portion C1 and the upper bent portion C2 are linearly extended, which is necessary for tilting the support main body 2. Since the amount of deformation of the front flange 21 is ensured, the column main body 2 is tilted at least as much as the conventional one without breaking the front flange 21 without using a special material or a complicated shape. The collision energy can be absorbed.

  In the present embodiment, the base 21a is tilted toward the rear flange 22 and the width of the web 23 at the upper end (lower bent portion C1) of the base 21a is reduced, whereby the bending rigidity at the lower bent portion C1 is increased. Since the size is reduced, the lower bent portion C1 is easily extended linearly. In addition, if the width of the web 23 at the upper end of the base portion 21a is reduced, it is possible to prevent the lower part of the support main body 2 from becoming unnecessarily heavy. Therefore, it becomes possible to reduce the weight of the protective fence support P. As a result, material costs can be reduced.

  Further, in the present embodiment, the rear flange 22 has a strip-like shape without bending, so the appearance of the protective fence support P is clean, and further, the design of the rear flange 22 is easy. Become.

Incidentally, the height difference h ₁ between the upper surface and the lower bent portion C1 of the base 1 may be larger than 200mm, but exceeds the 200mm, the bending moment generated on the lower side bent portion C1 by the collision load is reduced, Since it is difficult for the lower bent portion C1 to be straightened, it is preferable that the lower bent portion C1 is 200 mm or less as in the present embodiment. Further, when the height difference h ₁ between the upper surface and the lower bent portion C1 of the base 1 is below 30 mm, the possibility that the amount of deformation of the front flange 21 when deformed as the lower bent portion C1 becomes straight decreases Therefore, it is preferably 30 mm or more.

Further, the inclination angle theta ₁ of the base portion 21a, may be greater than 20 degrees but become bend the front flange 21 is conspicuous, because there is a risk that damage the neat appearance, preferably, the present embodiment It is desirable that the angle be 20 degrees or less.

Although the height difference h ₂ of the lower bent portion C1 and the upper bent portion C2 may be smaller than 30 mm, below the 30 mm, the lower bent portion C1 and the upper bent portion C2 is not easily extended in a straight line Therefore, it is preferably 30 mm or more as in the present embodiment. Although the height difference h ₂ of the lower bent portion C1 and the upper bent portion C2 may be larger than 100 mm, it exceeds the 100 mm, width of the web 23 at the upper bent portion C2 is increased bending stiffness in this position Becomes too high, and it is difficult for the upper bent portion C2 to be linearly stretched. Therefore, it is preferable that the upper bent portion C2 is 100 mm or less as in the present embodiment.

May also be smaller than the angle theta ₂ to 5 degrees with a plane parallel W and the inclined portion 21b on the rear flange 22, but if less than 5 degrees, the lower bent portion C1 and the upper bent portion C2 is straight Since the amount of extension of the front flange 21 secured by being stretched becomes small, it is preferably 5 degrees or more as in the present embodiment. Incidentally, the angle theta ₂ may be greater than 30 degrees, but if above 30 °, bending stiffness at this location the width of the web 23 at the upper bent portion C2 is increased becomes too high, the upper bent portion Since C2 becomes difficult to extend linearly, it is preferably 30 degrees or less as in the present embodiment.

Further, the inclination angle theta ₃ of the main portion 21c, may be larger than 20 degrees, but when more than 20 degrees, the intensity at this location width at the top is smaller web 23 there is a fear that insufficient It is preferable that the angle is 20 degrees or less as in the present embodiment.

  Note that the configuration of the protective fence support P may be changed as appropriate. For example, in the above-described embodiment, the base portion 21a, the inclined portion 21b, and the main body portion 21c of the front flange 21 are each flat (flat), but may be arcuate. Similarly, in the present embodiment, the rear surface of the rear flange 22 is planar, but it may be arcuate.

  Further, in the present embodiment, the width dimension of the front flange 21 is gradually reduced as it goes upward. However, the width dimension is not limited to this, and the illustration is omitted, but may be unchanged. In the present embodiment, the thickness of the front flange 21 is constant from the lower end to the upper end. However, the thickness is not limited to this, and although not illustrated, the thickness may be gradually decreased toward the top.

  In the present embodiment, the width dimension and thickness of the rear flange 22 are constant from the lower end to the upper end. However, the present invention is not limited to this, and illustration is omitted. It may be gradually reduced as you go.

  Although illustration is omitted, if necessary, reinforcing ribs may be provided at the corners formed by the upper surface of the base 1 and the rear surface of the rear flange 22.

  In the present embodiment, the guard fence support P in which the steel members are integrated by welding is illustrated. However, the material and the manufacturing method of the guard fence support P are not limited. It can be used as a cast product.

FIG. 6 shows a relationship between a load and a displacement amount when a horizontal load simulating an impact load is statically applied to the upper end portion of the column body 2.
The material of the protective fence support P used in the test is a general structural rolled steel (SS400) having a minimum tensile strength of 400 N / mm ² or more. The thickness of the base 1 is 19 mm, and the height of the column main body 2 (the distance from the upper surface of the base 1 to the upper end of the mounting portion 24) is 809 mm.

The width dimension at the lower end of the front flange 21 is 125 mm, and the width dimension at the upper end is 90 mm. The wall thickness of the front flange 21 is 6 mm. Height difference _{h 1} between the upper surface and the lower bent portion C1 of the base 1 is 171mm, the height difference _{h 2} between the lower bent portion C1 and the upper bent portion C2 is 70 mm. The inclination angle theta ₁ is 14 ° 10'28 base 21a ", the inclination angle theta ₂ is 9 ° 16'3 of the inclined portion 21b against the rear flange 22", the inclination angle theta ₃ of the main portion 21c is 1 ° 32 ' 15 ″.
The rear flange 22 has a width dimension of 44 mm and a wall thickness of 9 mm. The inclination angle theta ₄ of the rear flange 22 is 1 ° 20'9 ".
The width at the lower end of the web 23 is 115 mm, the width at the lower bent portion C1 is 68 mm, and the width at the upper bent portion C2 is 79.4 mm. The thickness of the web 23 is 6 mm.

  Experiments were conducted on two specimens (case 1 and case 2) formed of the same shape and the same material. As shown in FIG. 6, buckling occurred in the web 23 at 28.0 kN in case 1 and 28.6 kN in case 2, but the load dropped sharply until the displacement at the upper end of the column body 2 reached 30 cm. There was no. Since the displacement at the upper end of the column main body 2 reaches 30 cm and the load at the time is about 25 kN, the protective fence column P can sufficiently withstand the impact load at the time of vehicle contact / collision, and has a predetermined collision energy. It turns out that it has the characteristic which can be absorbed.

It is a perspective view of the guard fence for vehicles provided with the support | pillar for guard fences concerning embodiment of this invention. It is a perspective view of the support fence post according to the embodiment of the present invention. It is a figure which shows the support | pillar for protection fences concerning embodiment of this invention, Comprising: (a) is a front view, (b) is a side view, (c) is a rear view. It is an enlarged side view which shows the lower part of the support | pillar for protection fences concerning embodiment of this invention. (A) is a side view which shows the state which inclined the support | pillar for protection fences, (b) is a rear view. It is a graph which shows the relationship between the load and the amount of displacement when applying the horizontal load which simulated the impact load to the upper end part of the support | pillar for protection fences statically. (A) And (b) is a side view which shows the support | pillar for the conventional guard fence.

Explanation of symbols

P Guard fence post 1 Base 1a Bolt insertion hole 2 Post body 21 Front flange 21a Base 21b Inclined part 21c Main part 22 Rear flange 23 Web C1, C2 Bending part K Foundation R Road

Claims (7)

A support fence post having a pedestal fixed to a foundation built on the side of the road and a support column body erected on the pedestal,
The strut body includes a front flange facing the road, a rear flange disposed behind the front flange, and a web connecting the front flange and the rear flange.
The front flange has a base that rises from the pedestal, and an inclined part that rises obliquely upward from the upper end of the base toward the front side,
When a collision load is applied to the column main body from the road side, the column main body tilts backward while the bent portion formed by the base and the inclined portion is linearly extended. Guard post.   The support fence post according to claim 1, wherein a height difference between the upper surface of the pedestal and the bent portion is 30 mm or more and 200 mm or less.   The support fence post according to claim 1, wherein the base portion is inclined toward the rear flange side. The front flange has a main body that rises obliquely upward from the upper end of the inclined portion toward the rear side,
When a collision load acts on the column main body from the road side, a bent portion formed by the base portion and the inclined portion and a bent portion formed by the inclined portion and the main portion are straightened. 4. The support fence post according to claim 1, wherein the support body tilts backward. 5.   The support fence post according to claim 4, wherein a height difference between the two bent portions is 30 mm or more and 100 mm or less.   The support fence post according to any one of claims 1 to 5, wherein the rear flange has a strip shape without bending.   The support fence post according to claim 6, wherein an angle formed by a surface parallel to the rear flange and the inclined portion is 5 degrees or more and 30 degrees or less.

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