基于摩擦滑移的板式橡胶支座耗能试验

地震作用下支座剪切滑移可以耗散部分能量,减轻桥梁下部结构损伤。为研究中小跨径梁桥板式橡胶支座剪切滑移耗能性能,采用3组不同轴向压应力单面滑动支座与1组无滑移支座试验。分析了不同轴向压应力下支座剪切滑移现象、滞回曲线、等效刚度、等效阻尼比。结果表明:随着轴向压应力降低,支座的滑动位移显著增大,脱空明显,滞回曲线面积增大,耗能能力显著增强;但限制了支座自身等效剪切变形与等效刚度的发挥。中小跨径桥梁可利用支座摩擦滑移耗散地震中的能量,该研究成果为进一步评价服役混凝土梁桥的安全性和可靠性提供了量化力学指标。

Experimental Study on Energy Consumption of Rubber Bearing Based on Friction Slip

The shear slip of bearing under earthquake can dissipate part of energy and reduce the damage of bridge substructure. In order to study the shear energy dissipation performance of slab rubber bearings of small and medium span bridges, three groups of unilateral sliding bearings with different axial stresses and one group of non-sliding bearings were compared. shear slip phenomena, cyclic curves, equivalent stiffness and equivalent damping ratio of bearings under different axial stresses were analyzed. The results show that the sliding displacement, the void, and the hysteresis curve area of the bearing increase, and the energy consumption is significantly enhanced with the reduction of axial stress. However, the effective shear deformation and stiffness of the bearing itself are limited. Small and medium-span bridges can dissipate energy in earthquake by friction slip of rubber bearings The results of this study provide quantitative mechanical indexes for further safety and reliability evaluation of serving concrete beam bridges.