多向地震荷载作用下砂土场地震陷分析  

Seismic subsidence of sand ground subject to multidirectional earthquake load

作　　者：高广运[1,2] 聂春晓[1,2] 石超 宋健[4] 

机构地区：[1]同济大学地下建筑与工程系,上海200092 [2]同济大学岩土及地下工程教育部重点实验室,上海200092 [3]国网马鞍山供电公司,安徽马鞍山230061 [4]河海大学土木与交通学院,江苏南京210098

出　　处：《哈尔滨工程大学学报》2017年第7期1100-1106,共7页Journal of Harbin Engineering University

基　　金：国家自然科学基金项目(41372271)

摘　　要：砂土震陷的计算是岩土地震工程的重要问题之一,现有的以经验公式为主的砂土震陷计算方法简化了地震的多维特性。为解决这一问题,本文采用Abaqus有限元软件对地震作用下的砂土场地进行震陷分析,分别模拟砂土场地在单向、水平双向和三向地震荷载作用下的震陷发展规律,并对各方向最大加速度峰值时刻的震陷值和最终震陷进行了对比分析。研究发现震陷的发展经过迅速增长、平稳增加和缓慢发展三个阶段,水平双向地震动引起的震陷值大于水平单向,但小于两个方向荷载单独作用下的和,因此不能简单地采用两个单向荷载作用下震陷叠加等效双向荷载作用下震陷。三向地震荷载引起的震陷远大于水平双向荷载产生的震陷值,竖向地震荷载对场地震陷增大贡献明显。Calculation of the seismic subsidence of sand is an important issue in geotechnical earthquake engineering. Present empirical methodologies for estimating the seismic subsidence of sand simplify the multidimensionality of earthquakes. Therefore, seismic subsidence of sand under earthquake shock was analyzed via Abaqus finiteele-ment software. The development processes of seismic subsidence were simulated under unidirectional, bidirectional ,and multidirectional earthquake loads. The seismic subsidence at the largest acceleration and in every direction and the final subsidence were compared and analyzed. The study found that the development of seismic subsidence comprised three stages ： rapid growth, steady increase, and slow development. During these stages, the seismic subsidence under bidirectional excitation was larger than that under unidirectional earthquake load but smaller than the sum of two unidirectional results. Therefore, we cannot simply add the seismic subsidence generated under two unidirectional loads and make the result equivalent to the subsidence under the bidirectional load. The seismic sub-sidence generated under three-directional earthquake load was muchlarger than that induced by bidirectional horizontal seismic load. The vertical seismic load plays a huge role in seismic subsidence.

关 键 词：多向地震荷载 砂土震陷 数值模拟 峰值加速度 竖向地震荷载 震陷等效关系 震陷分析 

分 类 号：TU47[建筑科学—结构工程]