Experimental and theoretical study on vibration control of base-isolation with energy transducer

In order to evaluate the effects of structural control and energy transition for the base-isolation with energy transducer （BIET）, shaking table tests on a steel frame model （BIET system） with scale of 1：4 were conducted and the results were compared with the lead rubber beating （LRB） isolation system for the same model. Then numerical analysis of the system was carried out, in which the improved Wen analytic model was used to simulate the hysteretic law of transducers. The results show that the structural system can transform the partial earthquake energy to hydraulic energy ; furthermore, the effect of structural control can reach or be close to that of the LRB isolation system. The agreements between numerical analysis results and those of shaking table tests demonstrate the accuracy of the numerical model.

Application of LRB isolation technology in continuous girder bridges

This paper summarizes the superiority of lead-rubber beating （LRB） continuous girder bridges. The research method for isolation performance is discussed when pile-soil interaction is considered. By the finite element method and self-compiling program, a systematic study of the reliability of LRB continuous girder bridges is given by the use of different indicators, including the riding comfort of the LRB system, the pounding and dynamic stability when the LRB system is subjected to seismic excitations, and the reliability of the LRB system when subjected to other common horizontal loads. The results show that the LRB system has obvious advantages over the traditional continuous girder structure. The LRB isolation effect remains good even when pile-soil interaction is considered; the vertical rigidity of the LRB guarantees desirable riding comfort. The LRB demonstrates good reliability when subjected to the effects of braking, wind loads and temperature. However, it is also pointed out that the pounding of the LRB system subjected to earthquakes must be avoided, and the dynamic stability may be reduced when the LRB system has higher piers and generates a larger displacement in a strong earthquake. Useful advice and guidance are proposed for engineering application.

桥梁顺桥向抗震减震措施研究

针对某倒虹吸跨河大桥抗震问题 ,对聚四氟乙烯滑板支座、铅芯—橡胶支座和液体粘滞阻尼器三种减震方案与原设计板式橡胶支座结构顺桥向减震效果进行了对比分析研究 ,提出了 k=1.5 k N/ mm、μ=0 .2 5的GZY30 0型铅芯—橡胶支座减震方案为减震结构推荐方案。该推荐结构平均地震响应比原设计降低了 5 4 .3% ,减震效果显著。采取减震措施的桥梁及其倒虹吸钢管在地震作用下相当于设计烈度降低一度。