摩擦摆支座性能劣化对港珠澳隔震桥梁全寿命期抗震性能的影响

Effects of Performance Deterioration of Friction Pendulum Bearings on Seismic Behavior of Hong Kong-Zhuhai-Macao Isolated Bridges in Life-cycle Period

为研究采用摩擦摆支座的港珠澳隔震桥梁在氯盐腐蚀环境中抗震性能随时间的变化规律,针对前期完成的摩擦摆隔震支座人工加速腐蚀试验,拟合得出支座摩擦因数的变化曲线;进而对港珠澳隔震桥梁进行非线性时程分析,分析在不同地震波、不同峰值加速度、不同劣化时间节点下桥梁结构和支座响应随腐蚀时间的变化规律。研究结果表明:随腐蚀时间的增长,桥梁墩顶位移和加速度、墩底剪力和弯矩均呈增大趋势,支座位移则逐渐减小;在桥梁120年寿命期时,劣化幅度最大,达259.8%,说明摩擦摆支座在腐蚀环境下的性能劣化对港珠澳大桥全寿命期内的抗震性能产生了明显的不利影响,应及时对全寿命服役期内的桥梁进行检测与维护。

In order to investigate the change law of seismic behavior of Hong Kong-Zhuhai-Macao Bridge isolated bridge using the friction pendulum bearings under the chloride ions corrosion with time,based on artificial accelerated corrosion test on the bearing in previous tests,fitting change curves of friction coefficient of isolation bearing were obtained.Moreover,nonlinear time-history analysis of Hong Kong-Zhuhai-Macao Bridge isolated bridge was conducted.The change laws of responses of isolated bridge and bearing with the corrosion time under different seismic acceleration records,different peak ground accelerations and different corrosion time were analyzed respectively.The results show that,top displacement and acceleration,base shear force and bending moment of the bridge pier all show increasing trend with the growth of corrosion time,but the displacement of the isolation bearing gradually decreases with the increase of corrosion time.The largest value of behavior deterioration is up to 259.8% at the service life period of 120 years for bridge,which indicates that performance deterioration of frictionpendulum bearings under corrosion environment has an obvious unfavorable effect on the seismic behavior of Hong Kong-Zhuhai-Macao Bridge isolated bridge in life-cycle period,so it is necessary to detect and maintain the isolated bridge in its service period timely.