摘要
近几年发生的几次大地震均出现了远场长周期地震动的破坏现象,为了揭示自振周期较长的减隔震连续梁桥在远场长周期地震动作用下的动力响应特性,采用非线性时程分析的方法,分别研究了常规地震动和远场长周期地震动作用下减隔震连续梁桥的地震响应,以及远场长周期地震动作用下减隔震和非减隔震连续梁桥地震响应的差异。结果表明:与常规地震动作用相比,远场长周期地震动作用时减隔震连续梁桥的地震响应明显增大,但依然小于板式橡胶支座桥梁的地震响应。这说明,在常规地震动作用下,铅芯橡胶支座减隔震性能发挥良好,在远场长周期地震动作用时,其减隔震性能依然能够发挥,但发挥效应相对常规地震动作用时较弱。这一现象在有关隔震桥梁的设计中应予以关注。
In the major earthquakes of recent years, the damage phenomena of far-field long-period ground motion had occurred many times. In order to reveal the dynamic response characteristics of the continuous isolated bridge with longer- natural period under the far-field long-period ground motions, the nonlinear time-history method was used to study the response of the isolated continuous girder bridge under conventional ground motions and the far- field long-period ground motions, and seismic response differences between the isolated bridge and the non-isolated bridge under the far-field long-period ground motion. The results showed that, compared with the conventional seis- mic effect, the seismic responses of the isolated continuous girder bridge increased under the far-field long-period ground motions, but it is still less than the seismic responses of the bridge with plate rubber supports. It indicated that, under conventional ground motion, the lead-plug rubber bearing possesses good isolation performance; and under the far-field long-period ground motions, its vibration isolation performance can still work, but is weaker than that under conventional ground motions. Attention should be paid to this phenomenon in the design of concerned i- solated bridge.
出处
《自然灾害学报》
CSCD
北大核心
2016年第3期137-142,共6页
Journal of Natural Disasters
基金
国家自然科学基金项目(51108234
51178258)
江苏省自然科学基金项目(BK2011803)~~
关键词
远场长周期地震动
连续梁桥
减隔震效应
动力响应
far-field long-period ground motion
continuous girder bridge
vibration reduction and isolation
dy-
