基于小样本记录的柱面网壳结构地震响应评估  

EVALUATING THE SEISMIC EFFECTS ON A CYLINDRICAL LATTICE SHELL USING A SMALL NUMBER OF RECORDS

作　　者：李玉刚 范峰[2] 洪汉平[3] LI Yu-gang;FAN Feng;HONG Han-ping(School of Mechanics,Civil Engineering and Architecture,Northwestern Polytechnical University,Xi’an 710072,China;School of Civil Engineering,Harbin Institute of Technology,Harbin 150090,China;Department of Civil and Environmental Engineering,University of Western Ontario,London,Canada,N6A 5B9)

机构地区：[1]西北工业大学力学与土木建筑学院,陕西西安710072 [2]哈尔滨工业大学土木工程学院,黑龙江哈尔滨150090 [3]西安大略大学土木与环境工程系,加拿大伦敦N6A 5B9

出　　处：《工程力学》2020年第5期228-236,共9页Engineering Mechanics

基　　金：国家自然科学基金项目(51608445)。

摘　　要：结构的地震反应可以采用时程分析法或反应谱法来估计,在用时程分析法计算结构抗震设计需求时,中国抗震设计规范规定了选择3条或至少7条地震动记录的准则。可以用峰值加速度(PGA)或加速度反应谱(SA)来对地震动记录进行调幅,但用哪一个地震动强度参数来调幅为最佳还是未知的。该文针对柱面网壳的分析结果表明:合适的地震动强度参数取决于所需的结构反应,为降低由地震动记录间差异引起的结构最大杆件内力、支座反力或基底剪力的变异性,采用PGA调幅地震动记录要优于SA,而对于结构的最大位移反应则恰好相反。由于结构频谱十分密集以及受高阶振动模态的影响,采用反应谱法计算结构最大杆件内力或基底剪力是不合适的。同时,该文计算了采用3条和7条地震动记录准则获得的结构最大杆件内力和基底剪力的统计值,以期能为选择合适的地震动强度参数和地震动记录数量提供依据。The time-history analysis procedure and the response spectrum method are used to estimate the seismic responses. The Chinese design codes recommend a set of criteria to select and use three or seven ground motion records to calculate seismic design demands if the time-history analysis is used. It is unknown which one of the two options provide statistically more consistent estimations of the seismic design demands if the peak ground acceleration(PGA) or spectral acceleration(SA) is used to scale the records. The results in this study on a cylindrical lattice shell indicate that the preferred intensity measure for scaling depends on the response of interest. To reduce the variability in the maximum structural member forces, support reaction or base shear caused by record-to-record variability, the use of PGA for scaling is preferable to the use of SA. The preference is reversed if the maximum displacement is of interest. The results also show that the use of the response spectrum method is inadequate for this structural type if the maximum structural member forces or base shear are of interest, partly because the vibration frequencies are very closely spaced and the seismic load effects are affected by higher vibration modes. Statistics of the maximum structural member forces, support reaction and base shear are obtained by using three and seven record components. The results are used to make suggestions on the number of record components and the preferred intensity measure to evaluate the seismic design demands for structural members and supports.

关 键 词：网壳结构 抗震设计需求 调幅 统计 数值分析 

分 类 号：TU311.3[建筑科学—结构工程]