JPS6122684B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bridge expansion joint, in particular a load-bearing bridge expansion joint.

Load-supporting type bridge expansion joints, typified by finger joints, have recently been made using a large number of thin steel plates that are used as load-supporting materials in parallel, and both ends of the expansion joints are firmly fixed to anchoring materials, and the gaps are filled with A bridge expansion joint of synthetic construction filled with a rubber-like elastic material was proposed by the present inventor in JP-A-56-85004 and JP-A-56-85005. In this expansion joint, when a bridge surface load acts on the joint, the thin steel plate acts like a thin structural member with both ends fixed or a cantilever type thin structural member with the span extending to the center of the gap. It also utilizes the small resistance due to out-of-plane bending deformation of the thin steel plate against the expansion and contraction of the bridge, and the large resistance due to the in-plane bending deformation of the thin steel plate against the bridge surface load. The unique feature of this product is that it utilizes the small resistance of thin steel plates to out-of-plane deformation.

Although the basic idea of using thin steel plates is the same, the present invention is a new proposal that can further ensure load bearing capacity against bridge surface loads and improve the durability of expansion joints. be. This proposal uses multiple steel rods supported between thin steel plates to directly support the bridge surface load with the steel rods and rubber-like elastic material, transmit the load to the thin steel plates, and then transfer it to the anchoring material. Compared to the case where the load is transmitted directly from the rubber-like elastic material to the thin steel plate, the load can be spread widely, so there is no localized large load. The presence of steel rods can significantly improve the ease of peeling between steel plates. However, the presence of the steel rod restricts the deformation of the thin steel plate due to the expansion and contraction of the expansion joint, so it is necessary to devise ways to attach the steel rod so as not to obstruct this. In the present invention, a notch is provided in a thin steel plate and a steel rod is placed in the notch, or the steel rod is inserted into a hole provided in the thin steel plate.
The purpose is achieved through the play of notches and holes. However, with this structure, the steel bars can move freely, so when the bridge load is transferred from the steel bars to the thin steel plates, a shift occurs between the steel bars and the thin steel plates, and their relative positions change. . Rubber-like elastic materials are effective in preventing this. This is because the rubber-like elastic material restrains the displacement between the steel rod and the thin steel plate with its adhesive force and maintains their relative positions, while the relative deformation can be tolerated by the deformation of the rubber-like elastic material. The present invention constitutes a load-supporting expansion joint by the mutual cooperation of a rubber-like elastic material, a steel rod, a thin steel plate, and their anchoring material, and the bridge surface load supporting mechanism is the same as that of a grating. It is reliable and has excellent durability, and it has been devised to deal with the expansion and contraction of the bridge by making it easier to deform by bending the thin steel plate.

Furthermore, applying tension to the anchoring material, applying tension to the thin steel plate, and introducing compressive stress to the rubber-like elastic material as prestress has the effect of improving the mechanical properties of the rubber-like material against the bridge surface load. be. The expansion joint also has a reduced resistance to compression in the region of effective prestress, which can lead to an advantageous behavior of the joint.

The present invention has been made in view of these points, and has a structure in which a plurality of thin steel plates are arranged in a direction perpendicular to the bridge axis, and the plate surfaces are arranged in a vertical direction, and
The edges of each thin steel plate are fixed to a fixing material, and the plurality of thin steel plates have a frame structure having a plurality of steel rods supported astride these, and a space in this structure is filled with a rubber-like elastic material. A bridge expansion joint characterized by: A plurality of thin steel plates are arranged in a direction perpendicular to the bridge axis, with the plate surfaces facing vertically, and the edge of each thin steel plate is fixed to an anchoring member, and the plurality of thin steel plates are supported across them. After forming a frame structure with multiple steel rods, pulling the anchoring material of this frame structure and creating a state where multiple thin steel plates are stretched and displaced, the space is filled with a rubber-like material that has not hardened yet. and introducing compressive stress into the rubber-like elastic material by releasing the tension applied to the anchoring material when the rubber-like elastic material can satisfy predetermined properties. This is an expansion joint.

Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a perspective view of a specific example in which a folded thin steel plate 1, a U-shaped steel anchor 2, a steel rod 3 made of steel wire, and a rubber-like elastic material 4 are used in a part near the bridge surface. . Although not shown, the anchoring material 2 is firmly fixedly connected to the bridge end by bolts or other anchoring materials.

The thin steel plate 1 is bent in a broken line shape at a plurality of locations. As shown in the figure, if the thin steel plate has multiple bending points, the thin steel plate will easily bend under the bridge load, so it is necessary to increase the height of the thin steel plate so that it behaves like a deep beam. . A plurality of thin steel plates 1 are arranged in parallel in a vertical direction and with the same height, and both ends 1a of each thin steel plate 1 are fixed to fixing members 2 parallel to each other by rivets 6. Note that 1b is a hole for a rivet. The steel rod 3 is supported across a plurality of thin steel plates 1.
In this embodiment, a plurality of steel rods are installed passing through the vicinity of the upper edge of each thin steel plate 1. However,
A plurality of thin steel plates 1 arranged in a direction perpendicular to the bridge axis are arranged so that the plate surfaces are oriented vertically, and both edges 1 of each thin steel plate 1 are arranged.
A is fixed to a fixing member 2, and a framework structure is formed having a plurality of steel rods 3 supported across a plurality of thin steel plates 1. In the frame structure constructed in this way, the space 5 of each thin steel plate 1 is filled with a rubber-like elastic material 4 that has not hardened yet. At this time, the fixing material 2 is pulled to create a state in which a uniform elongation displacement is given to the plurality of thin steel plates 1, and when the rubber-like elastic material satisfies the predetermined properties, the fixing material 2 is added to the fixing material 2. If the tension is released, the following effects can be obtained. In this example,
A rubber-like elastic material is placed only near the bridge surface, and this is because this material serves as a filler while holding the thin steel plate, and prevents the thin steel plate from deforming in compression due to the bridge surface load. This is because it is used in some places, but it goes without saying that it may be filled entirely. Note that a plate material or other shaped steel material can be used for the fixing material 2, and methods such as welding can also be used to fix the thin steel plate 1 to the fixing material 2. Further, the steel rod may have any shape, such as a shaped steel, as long as it has the same function.

In Figures 2a, b, c, and d, a plurality of steel rods 3 are installed across a plurality of thin steel plates 1, each of which has both ends 1a fixed to a pair of parallel fixing members. In the explanatory diagrams showing the state in which the thin steel plate 1 is bent, a and b show an example in which the thin steel plate 1 is bent at multiple places, c shows an example in which the thin steel plate is bent at one place in the center, and d shows an example in which the thin steel plate 1 is bent at one place in the center. shows an example in which is not bent, and has a middle plate 2 as a fixing material in the center. Note that the bending mentioned here does not include the bending of the edges for fixing to the fixing material.

Figure 3 a, b, c, d, and e are all thin steel plates 1
Fig. 2 is a perspective view showing an example of the above, in which a and d are the notches at the upper edge of the upper end and the insertion position 1c of the steel rod 3;
Examples c and e are examples in which a hole is provided near the upper edge and this hole is used as the insertion position 1c for the steel rod 3, and b is an example in which a hole is provided in the bent part and this hole is used as the insertion position for the steel rod 3. d is one in which the height of the thin steel plate 1 is changed to better cope with the expansion and contraction of the expansion joint, and a rectangular cross-section material can be used as the steel bar. Furthermore, e is an example in which only one place in the center is bent, unlike the other examples which have a plurality of bending points.
Note that the windows formed in the thin steel plate are used to improve the adhesion between the rubber-like elastic material and the thin steel plate.

Since the present invention is configured as described above, it has approximately the following effects.

In other words, a plurality of thin steel plates arranged in a direction perpendicular to the bridge axis, especially thin steel plates with bent parts as in the example, are arranged so that the plate surfaces are in the vertical direction, and each edge is fixed to the anchoring material. It consists of a rubber-like elastic material filled in the space, and utilizes the high resistance due to the in-plane deformation of the thin steel plate against bridge surface loads, and the out-of-plane deformation of the thin steel plate against the expansion and contraction of the bridge. The structure is designed to take advantage of its low resistance to deformation.

The present invention proposes a new device for the expansion joint having such a structure to further improve the load resistance against bridge surface loads and the durability of the expansion joint. Compared to the case where the bridge surface load is directly transmitted from the rubber-like elastic material to the anchoring material via the thin steel plate, multiple steel rods are used to straddle the thin steel plate so that the load is distributed over a wide area and supported. ing. These steel rods not only help distribute the load, but also help integrate the rubber-like elastic material and the thin steel plate, and are effective in preventing the two from peeling off. This is important for improving the durability of expansion joints. However, when installing the steel rods, it is necessary to devise ways to prevent them from restricting the deformation of the thin steel plates as the expansion joint expands and contracts. In the present invention, a notch is provided in the thin steel plate so that the deformation of the thin steel plate is not restricted, and the steel rod is placed in the cutout, or the steel rod is inserted into a hole provided in the thin steel plate.
The deformation of the thin steel plate is not inhibited by the play of the notches and holes. However, with this structure, the steel rods can move freely, so when transmitting the bridge load from the steel rods to the thin steel plates, the relative positions of the steel rods and the thin steel plates should not change due to misalignment. There is a need. Rubber-like elastic materials act effectively against this. This is because the rubber-like elastic material restrains the displacement between the steel rod and the thin steel plate with its adhesive force and maintains their relative positions, while the relative deformation can be tolerated by the deformation of the rubber-like elastic material. The present invention aims to improve the strength and durability of an expansion joint made of a combination of rubber-like elastic material and bent thin steel plates by adding steel rods without impairing the function of the expansion joint. The load support mechanism is similar to grating and is reliable, and the steel rod support mechanism is designed using thin steel plates so as not to hinder the expansion and contraction of the expansion joint. Further, the steel rod has the effect of promoting the integration of the rubber-like elastic material and the thin steel plate, preventing peeling, and improving the durability of the expansion joint.

Furthermore, if a process is added in which the anchoring material is stretched, tension is applied to the thin steel plate, and compressive stress is applied to the rubber-like elastic material as a prestress, the mechanical properties of the rubber-like elastic material against the bridge surface load are further improved. Furthermore, with respect to expansion and contraction of the joint, the resistance to compressive displacement is reduced in the area of effective prestress, and the behavior of the expansion joint can be guided advantageously.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway perspective view showing an embodiment of the present invention, Fig. 2 is an explanatory view showing an embodiment of the shape of a thin steel plate, and Fig. 3 is a perspective view showing an embodiment of a thin steel plate. It is. In the drawings, 1 is a thin steel plate, 1a is an edge of the thin steel plate 1, 2 is a fixing member, 3 is a steel rod, 4 is a rubber-like elastic material, and 5 is a space.

Claims (1)

[Claims] 1. A plurality of thin steel plates arranged in a direction perpendicular to the bridge axis are arranged so that the plate surfaces are oriented vertically, and the edge of each thin steel plate is fixed to a fixing material, and the plurality of thin steel plates are 1. A bridge expansion joint comprising a frame structure having a plurality of steel bars supported astride these, and a space in this structure filled with a rubber-like elastic material. 2 A plurality of thin steel plates are arranged in a direction perpendicular to the bridge axis, with the plate surfaces facing vertically, and the edge of each thin steel plate is fixed to a fixing material, and the plurality of thin steel plates are supported by straddling them. A frame structure is formed with a plurality of steel rods, and the fixing material of this frame structure is stretched to create a state in which a plurality of thin steel plates are stretched and displaced, and then a rubber-like elastic material is filled into the space. , a bridge expansion joint characterized in that a compressive stress is introduced into a rubber-like elastic material by subsequently releasing the tension applied to the anchoring material.