• 欢迎访问ERC!
引用本文:
【打印本页】   【HTML】   【下载PDF全文】   查看/发表评论  【EndNote】   【RefMan】   【BibTex】
过刊浏览    高级检索
本文已被:浏览 31次   下载 0  
分享到: 微信 更多
长周期地震下大底盘基础隔震结构减震分析
李飞燕1, 王林建2, 吴应雄3
1.厦门大学嘉庚学院;2.云南省地震工程研究院;3.福州大学土木工程学院
摘要:
隔震结构等长周期结构易与长周期地震动中的低频成分产生类共振,从而加剧震害。大底盘结构上部体型收进,存在刚度突变,塔楼在刚度突变处引起的扭转效应远大于大底盘自身的扭转效应。收集了273条地震动信息并进行滤波处理,筛选了近场普通、近场脉冲、远场普通和远场谐和四类地震动,建立一个8度(0.2g)设防区的大底盘基础隔震结构,利用ETABS软件进行隔震和抗震模型在双向地震动下的非线性时程分析。对比计算结果表明:长周期地震动下基础隔震结构的隔震效果较普通地震动差,大底盘楼层减震率较塔楼显著降低;设防烈度下底盘层间位移角超过中国《建筑抗震设计规范》(GB50011—2010)的限值,罕遇烈度下隔震层位移超限,建议采用复合隔震技术或增设限位装置等措施;长周期地震动下基础隔震结构降低大底盘结构平-扭耦合效应并不显著,大底盘顶层扭转响应增大;在加速度峰值相同的长周期地震动下,基础隔震结构结构响应的增长幅度远大于抗震结构,建议规范中增加考虑长周期地震动的影响。
关键词:  长周期地震 大底盘结构 基础隔震 减震分析
DOI:
分类号:
基金项目:云南省青年地震科学基金资助项目,国家自然科学基金项目,漳州市自然科学基金项目
Seismic response reduction analysis of large chassis base-isolated structure under long-period ground motions
Li Feiyan1, Wang Linjian2, Wu Yingxiong3
1.Department of Civil Engineering,Xiamen University Tan Kah College;2.Yunnan Institute of Earthquake Engineering;3.College of Civil Engineering of Fuzhou University,
Abstract:
Long-period structures such as isolated structures tend to produce pseudo-resonance with low frequency components of long-period ground motions; thus, it intensifies the damage. The set-back of the large chassis structure has an abrupt change in stiffness; torsion effect of tower caused by the abrupt change in stiffness is more than that of large chassis itself. We collected 273 ground motions and filtered four types of ground motions, including the near-field ordinary, near-field pulse, far-field ordinary, and far-field harmonic. An 8-degree (0.2g) fortified large chassis base-isolated structure was established. ETABS program software was used to conduct nonlinear time history analysis on the isolation and seismic model under bi-directional earthquake ground motions. The comparison results show that the seismic isolation effect of the base-isolated structure under long-period ground motions was worse than that of the ordinary ground motions, when the seismic response reduction rate of the large base floor significantly decreased compared with that of the tower. When the inter-story displacement angle of the chassis under fortification intensity exceeds the limit of China’s Code for Seismic Design of Buildings (GB50011-2010), and so does the displacement of isolation layer under rare earthquake intensity, it is recommended to adopt composite seismic isolation technology or add limit devices. Under the condition of long-period ground motions, the base-isolated structure reduces the lateral-torsional coupling effect of the large chassis structure, but the torsion response of large chassis’ top layer increases. Under long-period ground motions with the same acceleration peak, the response of the base-isolated structure increases much more than that of the seismic structure, and it is recommended to add the consideration of the impact of long-period ground motions to the Code.
Key words:  Long-period ground motions  Large chassis structure  Base isolation  Seismic response reduction analysis