The service life of bridge rubber bearing pads
The normal service life of bridge rubber bearings is 60 years, and they also have to bear the vibration and seismic disaster loads during the installed period . The bridge bearing is closely bonded by rubber and cold-rolled steel plate, used to bear the point weight of highway bridges.
Characteristics of bridge bearings:
1. Having sufficient longitudinal bending stiffness and longitudinal loading capacity.
2. The actual effect of isolation is significant and stable. Having sufficient small horizontal bending stiffness ensures that the foundation cycle time of the building is increased to around 2-3 seconds or 3 seconds.
3. Having an appropriate damping ratio can reasonably digest and absorb the kinetic energy of earthquake disasters, and reduce the seismic disaster response of the upper structure.
4. It has a stable extensibility calibration function and can automatically calibrate instantaneous velocity in several earthquake disasters.
5. Simple structure, convenient installation, inspection, and repair.
6. Having sufficient performance, the bridge bearing has a normal service life of 60 years.
7. Having sufficient experience in engineering projects and successfully withstanding the test of seismic resistance levels.
8. Capable of withstanding continuous loads, fatigue, aging, and other characteristics
Preventive measures for bridge rubber bearings:
1.The bridge bearing installed surface layer of the pier top w should be repaired according to the elevation ,construction layout should be carried out. Draw an axis or center line at the top of the pier and verify it.
2. In addition to meeting the design concept requirements for the design elevation, the rubber bearing pads should also maintain two directional levels in the plan, and the slope of the four squares of the support should not exceed 2mm
3. The axis of the bridge rubber bearing should be parallel to the axis of the load-bearing beam. When installing foundation screws, the top of the screw rod wall should not be less than the height to width ratio of the nut.
4.For continuous beams constructed using the cantilever pouring method, it is usually necessary to temporarily fix the top beam section of the pier (i.e. the zero block) and the bridge pier in place.
5.Before merging, the axial force is borne by the temporary bridge bearing of each pier, while the supports are not supported. After merging, the axial force of the temporary bridge bearing shall be transformed according to the provisions of the axial force of the continuous beam support point. At this point, the adjustment of the bridge bearing pad reaction force should be based on the design elevation control axis force as the strength verification.