埋深对可液化场地地铁车站地震响应的影响

1)大连海事大学土木工程系,辽宁大连 116026; 2)大连海事大学安全工程系,辽宁大连 116026

岩土工程; 地铁车站; 埋深; 可液化场地; 数值模拟; Biot动力固结理论; 动力响应

Influence of burial depth on the seismic response of subway station in liquefiable subgrade
XU Minze1, CUI Chunyi1, YAO Yiyi1,WANG Guangbing1,

LIANG Zhimeng1, LI Chaoji1, and WANG Qifu21)Department of Civil Engineering, Dalian Maritime University, Dalian 116026, Liaoning Province, P.R.China 2)Department of Safety Engineering, Dalian Maritime University, Dalian 116026, Liaoning Province, P.R.China

geotechnical engineering; subway station; burial depth; liquefiable subgrade; numerical simulation; Biot dynamic consolidation theory; dynamic response

DOI: 10.3724/SP.J.1249.2020.03287

备注

为分析埋深对可液化场地地铁车站结构的地震动响应影响规律,在OpenSees开源程序平台和Biot动力固结理论基础上,采用修正的多屈服面塑性砂土动力本构模型,同时考虑结构动力非线性的纤维截面单元,建立饱和砂土场地-地铁车站结构相互作用数值计算模型,并分析了在地铁车站不同埋深情况下,场地的加速度反应谱及结构变形和内力的动力响应. 分析结果表明,随着车站结构埋深的减小,场地特征点处加速度β反应谱峰值变大,且各埋深工况均呈现出明显的场地放大效应; 随着车站结构埋深的增加,各关键截面动内力峰值变大,而对应的层间位移角极值和结构上浮量均呈现减小趋势,其中中柱上端部截面受埋深影响程度最为显著.

In order to study the effect of burial depth on the dynamic response of subway station structure, a numerical model of subway station structure embedded in saturated liquefiable subgrade is established based on OpenSees platform and Biot dynamic consolidation theory, in which a multi-yield surface model and a fiber-section element model are used to describe the cyclic plastic behavior of sand and structure respectively. Furthermore, the acceleration spectrum of subgrade and dynamic response of structural deformation and internal force under different burial depths of subway station are analyzed. The results show that with the decrease of the burial depth of the station structure, the peak of the β-spectrum of typical points of the site increases, and the site amplification effect is obvious on each burial depth condition. In addition, with the increase of burial depth of station structure, the peak value of dynamic internal force of each key section for station structure increases, while the corresponding maximum value of interlayer drift angle and the uplift of the structure decrease, in which the burial depth has the most significant effect on the dynamic behavior on the upper end section of the middle column.

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