Novel shock insulation system suitable for medium and small-span beam bridges

Abstract

The invention relates to a novel shock insulation system suitable for medium and small-span beam bridges. The novel shock insulation system comprises a plate-type rubber support, an embedded steel plate, a transverse X-shaped elastic-plastic stop block, a sliding chute, a longitudinal triangular blocking device and relevant auxiliary components. The transverse X-shaped elastic-plastic stop block is arranged in the sliding chute, the top of the transverse X-shaped elastic-plastic stop block is connected with a main beam through the sliding chute in the transverse direction of one bridge, and the bottom of the transverse X-shaped elastic-plastic stop block is fixedly connected with an abutment. The longitudinal triangular blocking device is fixedly connected with the main beam, and a certain gap is reserved between the longitudinal triangular blocking device and the abutment. Compared with an existing shock reduction and insulation technique, the novel shock insulation system is developed based on a bridge adopting the plate-type rubber support, the sliding friction effect of the plate-type rubber support is taken into consideration, and the novel shock insulation system has the advantages that relative displacement of pier beams is controlled, the earthquake damage to the lower structure is reduced, installation and replacement are easy and convenient, performance is reliable, and cost is low.

Description

technical field [0001] The invention belongs to the fields of bridge engineering and earthquake engineering, and in particular relates to a novel seismic isolation system suitable for beam bridges with small and medium spans. Background technique [0002] Beam bridges with small and medium spans, including simply supported girder bridges and continuous girder bridges with main girder sections such as T-beams, small box girders, and small slab girders, play an extremely important role in my country's increasingly developed highway traffic network. Bridges of this type of structure usually use plate-type rubber bearings, which are placed directly between the main girder and the lower pier abutment, without other connection measures, and a certain pier-beam lap length is set in the longitudinal direction of the bridge to adapt to the longitudinal displacement of the beam body At the same time, concrete blocks are generally set in the direction of the transverse bridge to limit ...

AI Technical Summary

Problems solved by technology

Due to the special structure and construction form of the plate rubber bearing on the small-and-medium-span beam bridge in my country, the relative sliding between the bearing and the steel plate at the bottom of the beam is prone to occur under strong earthquakes, resulting in excessive displacement of the beam body, but on the other hand, The sliding friction effect between the plate bearing and the beam body can also play a seismic isolation effect, reducing the seismic demand of the substructure

[0006] 2. Insufficient setting of the lap length of the longitudinal bridge to the pier beam

In the case of longitudinal sliding of plate bearings, the demand for earthquake displacement of the beam body is relatively large, and there are no other effective displacement restraint devices in the longitudinal direction of the bridge except for the sliding friction of the bearings, which will lead to serious earthquake damage such as bridge seating or even falling beams.

[0007] 3. The design of the concrete block of the transverse bridge is unreasonable

There are no standards or guidelines for the design of conventional concrete blocks in my country. Usually, designers only design structural reinforcement for concrete blocks, which makes it difficult to effectively control the seismic performance indicators such as strength and stiffness of the blocks. , so that it cannot guarantee that the block will realize its expected limit function under the action of earthquake

On the other hand, the ductility of the conventional concrete block itself is low, and the energy dissipation capacity is weak. Especially in the case of sliding of the plate bearing, the block is easily sheared when it is hit by the beam under the action of the earthquake.

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