【摘要】 为改善近断层地震动作用下隔震桥梁结构的抗震性能,基于Benchmark结构振动控制问题,研究附加黏滞阻尼器、磁流变(MR)阻尼器的组合隔震策略。非线性动力分析过程中,优化了黏滞阻尼器的阻尼系数和速度指数,并设计了分散模糊控制器来确定施加给磁流变阻尼器的电压。研究结果表明:采用黏滞阻尼器和磁流变阻尼器可提高隔震桥梁结构在近断层地震动作用下的安全性,结构绝大多数响应,尤其是隔震支座的变形得到明显减小;与采用黏滞阻尼器进行组合隔震相比,采用磁流变阻尼器的智能模糊控制方案出力相对较小、控制效果更好,同时,即使在外部电源供给中断的情况下,磁流变阻尼器仍然能发挥一定的作用,具有失效-安全的优点。更多还原

【Abstract】 To improve the seismic performance of isolated bridge subjected to near-fault earthquakes,benchmark structural vibration control for a seismically excited highway bridge is used as a numerical example to demonstrate the effectiveness of the hybrid isolation system with viscous damper and magnetorheological(MR) damper.In the process of nonlinear dynamic analysis,the damping coefficient and velocity index of viscous damper are optimized,and the decentralized fuzzy logic control method is employed to determine the voltage value applied to the MR damper.Results show that the hybrid isolation system based on the two kinds of damper can significantly improve the bridge’s safety under near-fault earthquake and the dynamic responses,especially the isolation bearing deformation are greatly reduced.In comparison with the passive viscous damper control,MR damper based on intelligent fuzzy logic control system has the advantage in requiring less control force and obtaining better control performance,furthermore,even without providing voltage,MR damper is also capable of mitigating the responses.更多还原