Buffer material

Abstract

To provide a cushioning material capable of simplifying replacement work.SOLUTION: A cushioning material 10 is attached to a horizontal displacement suppression member 20 arranged on a bridge pier B with a horizontal gap between it and a bridge girder A. The cushioning material 10 comprises: a cushioning body 11 formed with a plurality of through holes 11c penetrating in a vertical direction; a plurality of insertion members 12 respectively inserted through the through holes 11c; locking members 13 fixed respectively to protruding parts 12a of the plurality of insertion members 12 that protrude from an upper end of the cushioning body 11, and detachably locked to the horizontal displacement suppression member 20 by moving downward; and dropout prevention members 14 fixed to protruding parts 12b of the plurality of insertion members 12 that protrude from a lower end of the cushioning body 11, and preventing the insertion members 12 from dropping out of the through holes 11c.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a buffer material, and more particularly to a buffer material attached to a horizontal movement suppression member that suppresses horizontal movement of a bridge girder. [Background technology]

[0002] To prevent bridges from collapsing, horizontal movement suppression members that suppress the horizontal movement of bridge girders are sometimes attached to bridge piers. In this case, buffer materials are attached to the horizontal movement suppression members to reduce the impact when the bridge girders collide with the horizontal movement suppression members.

[0003] Generally, a stepped through hole is formed on the surface of the buffer facing the bridge girder in a direction perpendicular to this surface, and the buffer material is attached by inserting a bolt into this through hole and screwing a nut onto it.

[0004] Patent document 1 describes that a buffer is installed on a bridge fall prevention wall (horizontal movement suppression member) by embedding multiple mounting pieces with protruding upper and lower ends into the buffer so that they are flush with the mounting surface of the buffer, and inserting anchor bolts into the through holes formed in each protruding end.

[0005] Patent Document 2 describes a method of installing a buffer rubber on a concrete wall by embedding and gluing a bolt into the buffer rubber (buffer), attaching a mounting steel plate to the protruding upper end of the bolt using a nut, inserting the bolt into a through-hole formed in the mounting steel plate, and fixing the bolt to the concrete wall (horizontal movement suppression member). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 3599906 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-251411 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the gap between the buffer body attached to the horizontal movement suppression member and the bridge girder is set to a distance that allows horizontal movement of the bridge girder, and is very narrow. Therefore, it is almost impossible to attach a buffer body to a horizontal movement suppression member installed on a bridge pier. Therefore, horizontal movement suppression members with buffer bodies already attached have been installed on bridge piers. However, when replacing the buffer body due to deterioration over time or damage caused by earthquakes, the horizontal movement suppression member must be removed from the bridge pier, making the process of replacing the buffer material cumbersome.

[0008] In view of the above, an object of the present invention is to provide a cushioning material that can simplify replacement work. [Means for solving the problem]

[0009] The cushioning material of the present invention is a cushioning material that is attached to a horizontal movement suppression member that is placed on a bridge pier, with a horizontal gap between it and the bridge girder, and is characterized by comprising a cushioning body having a plurality of through holes that penetrate in the vertical direction, a plurality of inserting members that are inserted into the through holes, a locking member that is fixed to the portions of the inserting members that protrude from the upper end of the cushioning body and that moves downward to removably lock onto the horizontal movement suppression member, and a fall prevention member that is fixed to the portions of the inserting members that protrude from the lower end of the cushioning body and that prevents each of the inserting members from falling out of the through hole.

[0010] According to the buffer material of the present invention, the locking member is locked to the horizontal movement suppression member by moving the buffer material downward. Therefore, the buffer material, which is positioned upward at a predetermined position relative to the horizontal movement suppression member, can be attached to the horizontal movement suppression member by moving it downward. Therefore, unlike the conventional method in which attaching the buffer material to the horizontal movement suppression member requires horizontal work from the bridge girder toward the surface of the horizontal movement suppression member facing the bridge girder, it is now possible to attach the buffer material to a horizontal movement suppression member installed on a bridge pier. Furthermore, since the buffer material can be removed from the horizontal movement suppression member installed on the pier, the work of replacing the buffer material can be simplified.

[0011] Furthermore, since a locking member is fixed to the upper end of the insertion member and a fall-prevention member is fixed to the lower end, it is possible to reliably prevent the insertion member from falling off the buffer body. Note that "moving downward" does not strictly mean moving downward in the vertical direction, but also includes movement in directions including diagonally downward.

[0012] In the cushioning material of the present invention, it is preferable that each of the portions of the multiple insertion members protruding from the lower end of the cushioning body has a male thread formed thereon, and that the anti-fall-out member is fixed to each of the multiple male threads using a nut.

[0013] In this case, deformation of the buffer body can be more effectively prevented than when a drop-off prevention member is fixed to each insertion member. Also, since the fixing is done using a nut, the fixing work is simple and it is easy to adjust the degree of tightening to the buffer body.

[0014] In addition, in the cushioning material of the present invention, it is preferable that a male thread is formed on each of the portions of the multiple insertion members that protrude from the upper end of the cushioning body, and that each of the locking members is fixed to the male thread using a nut.

[0015] In this case, since the nuts are used for fastening, the fastening work is simple and it is easy to adjust the degree of fastening to the buffer body.

[0016] In the cushioning material of the present invention, for example, each of the locking members has a hook-shaped portion, and each of the horizontal movement suppressing members has a portion at its upper part that engages with the hook-shaped portion. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is an explanatory diagram showing a bridge collapse prevention structure using a buffer material according to an embodiment of the present invention. [Figure 2] Schematic longitudinal cross-section of a bridge collapse prevention structure. [Figure 3] FIG. 10 is a schematic side view showing a state in which a buffer material is attached to the horizontal movement suppression member. DETAILED DESCRIPTION OF THE INVENTION

[0018] A horizontal movement suppression cushioning material 10 (hereinafter simply referred to as cushioning material 10) according to an embodiment of the present invention will be described with reference to Figures 1 to 3. Note that Figures 1 to 3 are diagrams for schematically explaining this embodiment, and the dimensions are exaggerated.

[0019] The buffer material 10 is attached to a horizontal movement suppression member 20 installed on a bridge pier B for the purpose of isolating bridge girder A, such as the main girder of a bridge such as an elevated bridge, from seismic activity and preventing the bridge from collapsing. The horizontal movement suppression member 20 suppresses the horizontal movement of bridge girder A, and the buffer material 10 is installed with a specified gap between it and bridge girder A. The buffer material 10 suppresses the impact when bridge girder A and horizontal movement suppression member 20 collide.

[0020] The horizontal movement suppression member 20 includes a base bracket 21 fixed to the pier B, and a buffer bracket 22 to which the buffer 10 is attached.

[0021] The base bracket 21 is a box-like structure made by welding or other methods to a rectangular steel plate, with the side opposite the fixed side open and reinforced with multiple reinforcing plates. The base bracket 21 is fixed, for example, using nuts to a number of anchors that are installed in advance or fixed later to a concrete pier B (not shown).

[0022] The buffer bracket 22 is formed by fixing rectangular plates made of steel or the like by welding or the like. The buffer bracket 22 is fixed by welding or the like to an upper plate 21a that constitutes the upper part of the base bracket 21. The buffer bracket 22 has a rectangular mounting plate 22a that has a surface against which the buffer 10 abuts. The mounting plate 22a and the upper plate 21a of the base bracket 21 are connected by welding or the like with a plurality of plate-shaped reinforcing plates 22b.

[0023] The cushioning material 10 includes a cushioning body 11, an insertion member 12, a locking member 13, and a fall prevention member 14.

[0024] The buffer 11 has a rectangular flat surface 11a that comes into face contact with the mounting plate 22a of the buffer bracket 22, and a flat surface 11b that is parallel to this flat surface 11a and faces the surface of the bridge girder A across a specified gap, and is approximately rectangular plate-shaped overall.

[0025] The buffer 11 has a plurality of through holes 11c formed therein, which penetrate in the vertical direction when the buffer 11 is installed on the horizontal movement suppression member 20. The buffer 11 may be the same as a conventional buffer except for the through holes 11c formed therein, and may be made of, for example, rubber.

[0026] The inserting members 12 are inserted through the through holes 11c formed in the buffer body 11. An upper end 12a of the inserting members 12 protrudes upward from the upper end of the buffer body 11, and a lower end 12b of the inserting members 12 protrudes downward from the lower end of the buffer body 11. Male threads are formed on the upper end 12a and the lower end 12b. It is also possible to use, as the inserting members 12, cut bolts (long thread bolts) having male threads formed along their entire length.

[0027] The locking member 13 is formed by bending a rectangular piece made of metal such as steel. The locking member 13 is configured so that by moving the buffer material 10 downward, the buffer material 10 can be locked to the horizontal movement suppressing member 20, more specifically, to the upper end of the mounting member 22a of the buffer material bracket 22, and by moving the buffer material 10 locked to the horizontal movement suppressing member 20 upward, the buffer material 10 can be removed from the locked horizontal movement suppressing member 20.

[0028] Locking member 13 has a first piece 13b extending in a horizontal plane and having through hole 13a formed therein, through which upper end portion 12a of inserting member 12 is inserted. With the lower surface of first piece 13b abutting against the upper end surface of buffer body 11, locking member 13 is fixed to inserting member 12 by a nut 15 that screws onto upper end portion 12a of inserting member 12. In this way, by fixing first piece 13b of locking member 13 by nut 15, inserting member 12 is prevented from slipping out upward through through hole 11c.

[0029] The locking member 13 further has a second piece 13c that extends upward continuously from the first piece 13b. The second piece 13c is formed so that when the locking member 13 is fixed to the insertion member 12 with the nut 15, the surface of the mounting member 22a of the horizontal movement suppression member 20 that faces the bridge girder A is flush or approximately flush with the surface 11a of the buffer body 11.

[0030] The locking member 13 further has a third piece 13d that is continuous with the second piece 13c and extends rearward relative to the front bridge girder B. The third piece 13d is set to a length slightly longer than the thickness of the mounting plate 22a of the buffer bracket 22 to which the locking member 13 is hooked.

[0031] The locking member 13 further has a fourth piece 13e extending downward continuously from the third piece 13d. This fourth piece 13e is formed so that the surface of the fourth piece 13e facing the horizontal movement suppressing member 20 is flush or nearly flush with the surface 11b of the buffer 11 when the locking member 13 is fixed to the inserting member 12 with the nut 15. In this way, the second to fourth pieces 13c to 13e are formed in a hook shape that surrounds the upper end of the mounting plate 22a of the buffer bracket 22. The upper end of the mounting plate 22a is linear, but is shaped to engage with this hook-shaped portion.

[0032] The fall-prevention member 14 is a long, narrow rectangular piece made of steel or the like, with a width equal to or narrower than the thickness of the buffer body 11. A plurality of through holes 14a are formed in the fall-prevention member 14, corresponding to the positions of the through holes 11c formed in the buffer body 11. The fall-prevention member 14 is fixed in a state of abutment against the lower end surface of the buffer body 11 by threading nuts 16 onto the lower end portions 12b of the inserting members 12 with the lower end portions 12b inserted into the respective through holes 14a.

[0033] This prevents insertion member 12 from slipping out upward from through hole 13a, and also makes it possible to more effectively prevent deformation of buffer 11 by nuts 16 than when no fall-off prevention members 14 are present. Note that fall-off prevention members 14 may correspond to all of the through holes 11c formed in buffer 11, or a plurality of fall-off prevention members may be present in one buffer material 10, with each fall-off prevention member corresponding to a portion of the through holes 11c formed in buffer 11. Alternatively, each fall-off prevention member may correspond to an individual through hole 11c, like a washer.

[0034] The upper end surface of the buffer 11 may also be provided with a fall-off prevention member 14. In this case, the locking member 13 may be positioned on the upper surface of the fall-off prevention member 14. The fall-off prevention member 14 and the locking member 13 may be integrated, i.e., the first piece 13b of the locking member 13 may be replaced with the fall-off prevention member 14. Furthermore, the end of the first piece 13b and the fall-off prevention member 14 facing the surface of the bridge girder A is set back a predetermined distance from the flat surface 11b of the buffer 11 so that they are not subjected to impact when the bridge girder A and the buffer 11 collide. This predetermined distance is set to be equal to or greater than the maximum deformation that can occur in the buffer 11 when the bridge girder A and the buffer 11 collide.

[0035] A method for constructing a bridge collapse prevention structure using the above-described buffer material 10 will be described below.

[0036] In this construction method, first, the horizontal movement suppression member 20 is installed at a predetermined position on the pier B.

[0037] Thereafter, between the bridge girder A and the horizontal movement suppression member 20, the buffer material 10 is pushed in to a predetermined position while keeping the locking member 13 positioned above the upper end of the buffer material bracket 22.

[0038] Then, in this state, the buffer material 10 is moved downward so that the locking members 13 are caught on the upper end of the mounting plate 22a of the buffer material bracket 22. As a result, the second to fourth pieces 13c to 13e of each locking member 13 surround the upper end of the mounting plate 22a, and the buffer material 10 is attached to the horizontal movement suppression member 20. Note that between the bridge girder A and the upper end of the mounting plate 22a, which is the upper end of the horizontal movement suppression member 20, there is provided a gap in the vertical direction so that at least the locking members 13 can move toward the center (hereinafter referred to as the back direction) with respect to the axial cross section of the bridge girder A.

[0039] In this installed state, the cushioning material 10 can move in the rear or front direction, but is restricted by the reinforcing plate 22b. The position of the reinforcing plate 22b may be determined so that the cushioning material 10 cannot move.

[0040] As explained above, when the horizontal movement suppressing member 20 is installed on the pier B, the buffer material 10 is not attached to the horizontal movement suppressing member 20. Therefore, compared to the conventional case where a horizontal movement suppressing member with a buffer material attached is installed on the pier B, the gap between the horizontal movement suppressing member 20 and the bridge girder A is wider, which makes it possible to facilitate the work of installing the horizontal movement suppressing member 20.

[0041] Furthermore, by moving the buffer material 10 upward and then moving it toward the front, the buffer material 10 can be removed from the horizontal movement suppression member 20. In this way, the buffer material 10 can be freely attached and detached to the horizontal movement suppression member 20 installed on the pier B. Therefore, compared to the conventional case where the horizontal movement suppression member had to be removed from the pier B when replacing the buffer material, the replacement work of the buffer material 10 can be made easier.

[0042] The present invention is not limited to the above-described cushioning material 10 and can be modified as appropriate. For example, the specific configurations of the components of the cushioning material 10 and the horizontal movement suppression member 20 are not limited to those described above. For example, the shape of the locking member 13 is not limited to that described above as long as it can be removed from the horizontal movement suppression member 20 by moving downward, and it may have a rounded hook shape, for example.

[0043] Also, a case has been described in which the buffer material 10 can be removed simply by moving it upward from the horizontal movement suppression member 20 installed on the pier B. However, this is not limited to this, and for example, the buffer material 10 may be moved while the locking member 13 is kept hooked on the upper end of the mounting plate 22a, so that the upward movement of the buffer material 10 is suppressed by a suppression member (not shown). Also, the base bracket 21 of the horizontal movement suppression member 20 may be a flat plate that is placed on the pier B and fixed with a number of anchors. [Explanation of symbols]

[0044] DESCRIPTION OF SYMBOLS 10... Horizontal movement suppression buffer material, buffer material, 11... buffer body, 11a, 11b... flat surface, 11c... through hole, 12... insertion member, 12a... upper end (portion protruding from the upper end of the buffer body), 12b... lower end (portion protruding from the lower end of the buffer body), 13... locking member, 13a... through hole, 13b... first piece, 13c... second piece, 13d... third piece, 13e... fourth piece, 14... fall prevention member, 14a... through hole, 15, 16... nut, 20... horizontal movement suppression member, 21... base bracket, 21a... upper plate, 22... buffer material bracket, 22a... mounting plate, 22b... reinforcing plate, A... bridge girder, B... bridge pier

Claims

1. A buffer material that is replaceably attached to a horizontal movement suppression member arranged on a bridge pier with a horizontal gap between the bridge girder and the buffer material, the horizontal movement suppression member includes a buffer bracket including a mounting plate having a surface against which the buffer material abuts; The buffer material is a plate-shaped buffer body having a flat surface that is in surface contact with the mounting plate and a flat surface that is parallel to the flat surface and faces the surface of the bridge girder across a predetermined gap, and having a plurality of through holes that penetrate in the vertical direction; a plurality of long threaded bolts inserted into the through holes, respectively; a locking member that is fixed to each of the portions of the plurality of long-threaded bolts that protrude from the upper end of the buffer body and that is removably locked to the mounting plate when the buffer body moves downward, the locking member comprising: a first piece extending horizontally and having a through hole through which the upper end of the long-threaded bolt is inserted; a second piece extending upward from the first piece; a third piece extending rearward from the second piece relative to the front bridge girder; and a fourth piece extending downward from the third piece; and a fall prevention member fixed to each of the multiple long-threaded bolts at a portion protruding from the lower end of the buffer body, preventing each of the long-threaded bolts from falling out of the through hole.

2. The cushioning material according to claim 1, characterized in that the portions of the multiple long-threaded bolts that protrude from the lower end of the cushioning body each have a male thread formed thereon, and the anti-fall-out member is fixed to each of the multiple male threads using a nut.

3. The cushioning material according to claim 1 or 2, characterized in that the portions of the plurality of long-threaded bolts that protrude from the upper end of the cushioning body are each formed with a male thread, and the locking members are each fixed to the male thread using a nut.

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