JP2777919B2 - Bridge girder support method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a supporting method for providing an elastic supporting body to a superstructure including a bridge, an overpass, and other bridge girders.

[Conventional technology]

Conventionally, elastic bearings for supporting bridge girders are concrete loads such as floor slabs that are cast when bridge girders are installed, the amount of deflection caused by the introduction of prestressing force of prestressed concrete bridge girders, and seismic loads and wind loads acting on bridge girders. And the amount of deflection caused by the movement of the vehicle, temperature changes in the bridge girder,
The design is made in consideration of the amount of expansion and contraction caused by concrete shrinkage and drying. In addition, bridge girders such as curved bridges and diagonal bridges are designed in consideration of the vertical gradient or traverse gradient in addition to the deflection and expansion and contraction described above. Since there is a large error in the manufacture and construction of the elastic bearing, the allowable rotation angle and the like of the elastic bearing are designed to be large in consideration of the error.

If the bridge girder has a vertical slope or crossing slope such as a diagonal bridge or a curved bridge, as shown in FIG.
At 20, the bearing surfaces of the bridge girder G and the elastic support S are parallel to the pier B so that the elastic support S can be installed horizontally.

[Problems to be solved by the invention]

However, increasing the allowable rotation angle of the elastic bearing means increasing the thickness of the elastic bearing, in other words, making the elastic bearing tall, and therefore the load bearing capacity of the elastic bearing. Is reduced, causing buckling.

Also, the work of horizontally mounting the elastic bearings on the longitudinal or transverse gradient of the bridge girder is extremely complicated, and the parallelism tends to be out of order, which is a serious problem in terms of construction efficiency.

The present invention has been made in view of the above-mentioned circumstances, and has been made to solve the problems of the above-described conventional technology. It is an object of the present invention to provide a method for supporting a bridge girder that can tolerate errors.

B. According to the first method of the present invention, a method for supporting a bridge girder by an elastic bearing body installed on a foundation such as a pier or an abutment and having a rubber pad interposed therebetween is provided. , A sole plate having a convex curved surface portion is placed on the upper surface of the elastic bearing member installed on the foundation, and the lower surface of the bridge girder slides with the convex curved surface portion at a position opposed to the elastic bearing member. A concave curved seat is provided so as to be in contact with the bridge girder, a pre-process for absorbing the rotational displacement of the bridge girder caused by an error in the design, manufacture, and construction of the bridge girder by sliding the convex curved surface portion and the concave curved seat, and It is characterized by comprising a post-process of fixing the lower surface and the sole plate.

According to the second support method of the present invention, in the method of being installed on a foundation such as a pier or an abutment and supporting a bridge girder by an elastic support body with a rubber pad interposed, a concave curved seat is provided on the upper surface of the foundation. A sole plate having a convex curved surface portion which can be slidably contacted with the concave curved surface seat is fixed at a position opposed to the base upper surface of the elastic bearing body, and errors in design, manufacture and construction when the bridge girder is erected. And a post-process of fixing the upper surface of the foundation and the sole plate by absorbing the rotational displacement of the bridge girder caused by the sliding of the concave curved surface seat and the convex curved surface portion.

[Action]

The parallelism of the bearing surface between the elastic beam and the bridge girder caused by the concrete load of the floor slab or the like introduced during the construction of the bridge girder, the deflection caused by the introduction of the stress of the prestressed concrete bridge girder, or the design / manufacturing error during the construction of the bridge girder. The irregularities are absorbed by the curved surface consisting of the convex curved surface and the concave curved seat,
There is no deformation such as deflection of the elastic bearing body during bridge girder construction.

〔Example〕

An embodiment of the bridge girder support method of the present invention will be described based on the ground.

 1 to 3 show a first embodiment thereof.

FIG. 1 is a longitudinal sectional view of a concrete bridge girder including a bearing portion in a pre-process stage when the bridge is erected, FIG. 2 is a partially enlarged structure thereof, and FIG. 3 is a structure of the final process stage. FIG. 4 shows an example in which the bearing method of the present invention is applied to a diagonal bridge.

In the figure, G is a concrete bridge girder as an upper structure, and B is a lower structure such as a pier or abutment on which a bearing is mounted and the load of the concrete bridge girder G is transmitted to the foundation via the bearing.

An elastic bearing S is interposed between the concrete bridge girder G and the lower structure B.

The elastic bearing body S of the present embodiment comprises a rubber pad 1 and a steel plate 2 (2A: upper steel plate, 2B: lower steel plate) integrally fixed to the upper and lower sides of the rubber pad 1. The upper steel plate 2A of the elastic bearing body S The sole plate 4 is fixed and mounted on a pedestal 5 formed on the lower structure B by mortaring.

In this embodiment, the elastic bearing body S is a single-layer rubber pad. However, it is a matter of course that a multi-layered structure in which steel plates and rubber pads are alternately stacked is used.

A spherical projection 7 projects from the center of the upper surface of the sole plate 4, and a sliding member 8 is fitted on the spherical projection 7, thereby forming a convex spherical part 9.

On the other hand, on the lower surface of the concrete bridge girder G, a concave spherical seat 10 for receiving the above-mentioned convex spherical portion 9 is formed at a position corresponding to the elastic bearing body S. In this embodiment, the concave spherical seat 10 includes a sliding member 11 embedded and fixed to the lower surface of the concrete bridge girder G.

The convex spherical portion 9 and the concave spherical seat 10 are slidably in contact with each other via their sliding members 8 and 11 so as to be slidable in a spherical shape, and constitute a "spherical portion". In the spherical portion, a predetermined gap 13 is held between the upper surface of the sole plate 4 and the lower surface of the bridge girder so that the spherical portion can freely rotate.

Due to the configuration of the spherical portion, the concave spherical seat 10 is rotatable in all directions with respect to the convex spherical portion 9, and further, the engagement between the convex spherical portion 9 and the concave spherical seat 10 with respect to horizontal displacement. Thus, the displacement is transmitted to the rubber pad 1.

The method of supporting the concrete bridge girder G of this embodiment is performed in the following procedure.

FIG. 1 shows the preceding step, and FIG. 3 shows the final step.

 Hereinafter, description will be given based on the construction procedure.

(1) The elastic support S is installed on the pedestal 4 of the lower structure B.

(2) The sole plate 5 having the convex spherical portion 9 is placed and fixed on the upper surface of the elastic support S.

(3) A concave spherical seat 10 is provided on the lower surface of the concrete bridge girder G at a position opposite to the elastic bearing body S.

(4) The convex spherical portion of the sole plate 5 is slidably disposed on the concave spherical seat 10 to support the bridge girder G on the elastic bearing body. At this time, even if the deviation of the parallelism occurs between the elastic bearing member S and the formwork C, the deviation of the parallelism is absorbed by the spherical portion and is not transmitted to the rubber pad 1 under the same.

(5) After the irregularity of the parallelism due to the production / construction is absorbed by the spherical portion, the gap 13 between the elastic bearing member S and the concrete bridge girder G is filled and closed with the binder 15. The binder is non-shrinkable, and for example, range mortar, epoxy resin and the like are preferably used.

According to the method of this embodiment, the convex spherical portion 9 of the spherical portion and the concave spherical seat 10 are rotatable in all directions, so that the parallelism of the bearing surface of the elastic bearing member S due to a manufacturing error of the concrete bridge girder G. Is not transmitted to the rubber pad 1, the thickness of the rubber pad 1 can be reduced accordingly, and the load supporting ability is improved.

Further, after the concrete bridge girder G is cast, the gap 13 between the bridge girder G and the elastic bearing member S is closed by the solidifying agent 13 so that the rotation of the spherical portion becomes impossible. Is transmitted to the rubber pad 1 and is effectively absorbed.

Further, the spherical portion resists the horizontal force acting on the bridge girder G by the engagement between the convex spherical portion 9 and the concave spherical seat 10, so that the expansion and contraction due to the temperature change of the concrete bridge girder as it is is performed by the rubber pad 1 as it is. And the expansion and contraction is effectively absorbed.

Furthermore, since the rotational displacement in all directions is absorbed in the spherical portion, the position adjustment during the construction of the concrete girder G is performed in this portion, and the convenience that the workability is improved is generated.

 FIG. 5 shows a second embodiment of the present invention.

In this embodiment, a concave spherical seat 10 is formed on the upper surface of a lower structure B such as a bridge girder or an abutment, and the bridge girder G is formed on an upper surface of an elastic bearing S.
And the sole plate 4 is fixed to the lower surface of the elastic bearing member S. When the bridge girder is erected, the convex spherical portion 9 formed on the lower surface of the sole plate 4 slides on the concave spherical seat 10. Support as much as possible. After the bridge girder G is erected,
By filling and closing the gap between the sole plate 4 and the lower structure B with the binder 15, the sole plate 4 and the lower structure B are fixed.

Thus, even when the degree of parallelism is deviated between the lower structure B and the bridge girder G when the bridge girder G is erected, the deviation of the parallelism is transmitted to the sole plate 4 via the elastic bearing S. A convex spherical portion 9 of the sole plate 4 and a concave spherical seat of the lower structure B.
Since the rubber pad 1 is absorbed by sliding contact with the rubber pad 10, there is no deformation of the rubber pad 1 due to the deviation.

In the above embodiment, the concrete bridge girder has been described. However, the same effect can be obtained with a steel bridge girder.

Further, the present invention is not limited to the above embodiment, and various design changes can be made within the scope of the basic technical idea of the present invention. That is, the following embodiments are included in the technical scope of the present invention.

The convex spherical portion 9 and the concave spherical seat 10 are not limited to spherical surfaces but may be cylindrical surfaces.

As shown in FIG. 6, it is possible to adopt a mode in which the concave spherical washer 17 is projected from the lower surface of the concrete bridge girder G, and the convex spherical portion 9 is fitted into the concave portion 17a.

The spherical portion may be brought into sliding contact with the spherical projection 7 of the sole plate 4 and the bridge girder directly without passing through the sliding members 8 and 11.

In addition to filling and closing the gap between the sole plate and the bridge girder or foundation with mortar, insert appropriate interposers,
In some cases, they may be fixed to each other by welding.

C. According to the method for supporting a bridge girder of the present invention, a deviation in parallelism caused by a manufacturing error of the bridge girder is absorbed by the curved surface portion, and the burden on the rubber pad can be reduced.

Also, after the bridge girder is completed, the gap between the bridge girder and the elastic bearing is closed and fixed.
Expansion and contraction caused by temperature change of the bridge girder and rotational displacement caused by traffic of the vehicle are effectively absorbed by the rubber pad.

Further, the rotational displacement at the spherical portion adjusts the position of the bridge girder during the erection, thereby improving workability.

[Brief description of the drawings]

The drawings show an embodiment of a method for supporting a bridge girder according to the present invention. FIG. 1 is a cross-sectional view showing a pre-process stage of a bearing portion of the embodiment, FIG. FIG. 4 is a cross-sectional view of a support part in a post-process stage, FIG. 4 is an exemplary view of a supporting mode of a concrete girder, FIG. It is another aspect figure of. FIG. 7 is a view showing a state in which a conventional bridge girder is erected. G: Bridge girder, B: Substructure, S: Elastic bearing, 1 ...
... Rubber pad, 4 ... Sole plate, 9 ... Convex curved surface, 10 ... Concave curved seat

Claims (4)

(57) [Claims] 1. A method of supporting a bridge girder by means of an elastic supporter mounted on a foundation such as a pier or an abutment and having a rubber pad interposed therebetween, wherein the elastic supporter installed on the base has a convex curved surface portion on an upper surface thereof. On the underside of the bridge girder, a concave curved seat is provided on the lower surface of the bridge girder so as to be in sliding contact with the convex curved surface portion. A pre-process of absorbing the rotational displacement of the bridge girder caused by the error of the bridge girder by sliding the convex curved surface portion and the concave curved seat, and a post-process of fixing the lower surface of the bridge girder and the sole plate. Support method. 2. A method for supporting a bridge girder by means of an elastic bearing body mounted on a foundation such as a pier or abutment and having a rubber pad interposed therebetween, wherein a concave curved surface seat is provided on an upper surface of the foundation, A sole plate provided with a convex curved surface portion capable of slidingly contacting the concave curved seat is fixed at a position facing the upper surface of the foundation, and the rotational displacement of the bridge girder caused by an error in design, manufacture, and construction when the bridge girder is erected. A method for supporting a bridge girder, comprising: a pre-process for absorbing by sliding between a concave curved seat and a convex curved portion; and a post-process for fixing an upper surface of a foundation and a sole plate. 3. The method for supporting a bridge girder according to claim 1, wherein the convex curved surface portion and the concave curved surface seat have a spherical shape. 4. The method of supporting a bridge girder according to claim 1, wherein the convex curved surface portion and the concave curved surface seat have a cylindrical surface shape.