三维隔震连续梁桥模型结构地震模拟振动台试验  

Shaking Table Tests on Seismic Simulation of Three-dimensional Isolated Continuous Girder Bridges

作　　者：贾俊峰[1,2] 赵建瑜[1] 郭扬 欧进萍[3] 

机构地区：[1]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124 [2]招商局重庆交通科研设计院有限公司桥梁工程结构动力学国家重点实验室,重庆400067 [3]哈尔滨工业大学土木工程学院,哈尔滨150090

出　　处：《中国公路学报》2017年第12期290-298,共9页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51578030);桥梁工程结构动力学国家重点实验室开放基金项目(201602);桥梁结构抗震技术交通行业重点实验室开放基金项目(201602)

摘　　要：为发展作者研发的新型三维隔震装置,研究不同强度、不同特性地震作用下三维隔震连续梁桥的地震响应和三维隔震效果,设计并制作了一座1/25缩尺比例的三维隔震三跨连续梁桥和单跨水平隔震梁桥模型结构,设计了适合于桥梁模型的三维隔震支座和常用普通叠层橡胶隔震支座。在此基础上,对三维隔震连续梁桥和水平隔震单跨梁桥进行水平和竖向地震模拟振动台试验。研究结果表明:在几乎所有地震作用过程中,所研发的三维隔震支座能安全、有效地发挥作用,试验结束后三维隔震支座没有发生损坏。水平地震作用下,无论地震强度大小三维隔震支座和水平隔震支座都具有较好的水平隔震效果,主梁水平加速度减震效果可达50%~80%。近断层脉冲型地震动作用下,铅芯橡胶支座的水平隔震效果明显优于普通叠层橡胶支座。竖向地震作用下,采用普通叠层橡胶支座的单跨梁桥主梁竖向峰值加速度可能会明显放大,最大可能放大近1倍;即使部分地震激励下峰值加速度没有放大,在局部时段仍有明显放大现象,但是采用三维隔震支座的连续梁桥主梁竖向峰值加速度比墩顶竖向峰值加速度一般可减小30%左右,最多可达50%,且基本没有出现局部时段放大现象。三维隔震梁桥在水平和竖向地震作用下都表现出良好的隔震效果,为三维隔震技术在桥梁工程中的应用提供了依据。To develop a new type of three-dimensional （3D） isolator proposed by authors and investigate seismic responses and 3D isolation effect of 3D isolated continuous girder bridges under different seismic intensities and characteristics, a 1/25 scaled three-span continuous girder bridge with 3D isolator bearing （3DIB） and a single-span girder bridge with the common natural rubber bearing （NRB） only for horizontal isolation were designed and manufactured. The 3DIB and NRB were designed and selected for the bridge model test. On this basis, the horizontal and vertical seismic simulation shaking table tests were respectively carried out on the three-span and single-span isolated continuous girder bridge models. The results show that the developed 3D isolation bearing takes effect safely and effectively with no damage under almost all seismic excitations after the test. There is no damage on three-dimensional isolation bearing after the test. Under the horizontal earthquake action, both 3DIB and NRB reveal favorable horizontal isolation effect with 50%-80% for horizontal acceleration of main girders. The horizontal isolation effect of 3DIB with lead-core laminated rubber component is obviously better than that of NRB under near-fault pulse-like ground motions. Under the vertical seismic action, the peak vertical acceleration of the single-span girder isolated by NRB may obviously increase. The maximum acceleration may be double that of the original one. The amplitude may be enlarged in some time although the peak value is not amplified in some excitations. The peak vertical acceleration of the continuous girder with 3DIB will decrease by 30%, even up to 50%, and there is basically no local amplification in some time. The 3D isolated bridge shows satisfactory isolation effect under horizontal and vertical seismic excitations, which provides the valuable basis for 3D isolation technology applied in the bridge engineering.

关 键 词：桥梁工程 三维隔震支座 振动台试验 三维隔震桥梁 近断层地震动 竖向隔震 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]