中文摘要：

通过分析黄土震陷物理力学机制,将影响震陷的主导因素归纳为粘聚力与内摩擦角（土体强度特征）、孔隙比（土体沉降特征）和外部动荷载特性（能量输入特征）等3方面。在此基础上,推导了应用孔隙比描述震陷系数的定量关系;利用摩尔-库伦破坏准则,提出了考虑动应力和固结应力的应力比概念,用以刻画动载输入对土体结构强度的影响;结合室内动三轴试验数据,给出了孔隙比压缩量与应力比之间的定量统计关系。耦合以上分析结果,建立了基于物理力学机制的求算地震动作用下黄土残余应变（震陷系数）的数学估算模型。

英文摘要：

Under analyzing the physical-mechanical mechanism of seismic subsidence of loess （SSL）, the dominant factors affecting SSL could be come down to as follows： cohesive strength, internal friction angle, void ratio and dynamic loading features. The factors of cohesive strength and internal friction angle represent the characteristics of soil structure strength, while void ratio influences the final seismic subsidence magnitude of soil mass. Meanwhile, the quantitative relation between the void ratio and seismic subsidence coefficient （SSC） is educed through physical and mathematical analysis. Based on the Mohr-Coulomb failure criterion, the stress ratio, which could reflect the influences of dynamic stress on the structure strength of soil mass, is defined by considered dynamic stress and consolidation stress. Grounding on the laboratory data of SSL through dynamic triaxial test, the quantitative statistical relation between the compression volume of void ratio and stress ratio is investigated. Consequently, the mathematical estimation model applied the physical-mechanical mechanism of SSL is established to estimate the residual strain （seismic subsidence coefficient） of loess due to ground motion loading.