近断层地震下楼层竖向加速度影响因素分析  

Analysis of factors affecting vertical peak floor acceleration demands under near-fault ground motions

作　　者：戴靠山 钱雨凡 王健泽 DAI Kaoshan;QIAN Yufan;WANG Jianze(Department of Civil Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学土木工程系,四川成都610065

出　　处：《世界地震工程》2021年第2期192-202,共11页World Earthquake Engineering

基　　金：国家自然科学基金(51878426,U1710111);成都市科技项目(2019-GH02-00081-HZ);中央高校基本科研业务费(20826041E4193)。

摘　　要：现阶段基于性能的抗震设计思想不仅关注结构自身体系的安全,而且保护非结构构件在地震作用下使用功能完好。对于工业建筑结构,生产设备在地震作用下受损会影响震后功能恢复。加速度敏感型非结构构件一般采用楼层加速度指标来量化其地震损伤程度。以三个不同高度的钢抗弯框架规则结构体系为研究对象,采用与竖向目标谱匹配的近断层非脉冲和脉冲地震动作为竖向地震输入,考察不同质量不规则程度下,楼层竖向绝对加速度随建筑高度的变化趋势,并从反应谱角度分析不规则质量分布对楼层加速度响应的影响。结果表明:4层结构在非脉冲地震作用下楼层顶层处竖向绝对加速度是地面竖向峰值加速度的5倍之多,某一层质量的突变会引起该层及其他楼层竖向绝对加速度的明显变化。另外,对现有计算楼层竖向加速度响应的经验公式进行验证,发现美国ASCE 7-16规范的估计结果偏于保守。The performance-based seismic design theory has been developed with the intention of focusing on the safety of the structural system and protecting non-structural components from earthquakes.For industrial structures,equipment damage due to earthquake would result in disruption of operation.Generally,floor acceleration demands are used to quantify the seismic response of non-structural components.In this study,special steel moment-resisting frames are focused and near-fault non-pulse and pulse ground motions compatible with the vertical target design spectrum are used as inputs.The distribution of the vertical peak floor acceleration demands(PFA v)along the height of the structure with irregular mass distribution is considered.In addition,the influence of irregular mass distribution on floor acceleration response is studied from the view of floor response spectrum.The results presented in this study show that the vertical peak floor acceleration amplification factor on the uppermost story of 4 floor structure under the non-pulse ground motions can surpass the value of 5 and the story where the mass irregularity is can significantly influence the PFA v of the whole structure.Moreover,the empirical equations for predicting the vertical seismic demands are assessed and the results show that the ASCE 7-16 is conservative.

关 键 词：钢抗弯框架 近断层地震动 楼层竖向绝对加速度 质量不规则 

分 类 号：TU375.4[建筑科学—结构工程]