【摘要】 通过分析黄土震陷的物理过程及其力学机制,指出非饱和黄土震陷实质上是土体广义固相介质响应外部动荷载作用的再固结过程。将影响黄土震陷的主导因素归纳为两方面,即土体广义固相介质的强度、体积特征和外部动荷载特征。介质的强度特征可通过引入土工试验获取的参数(粘聚力和内摩擦角)来宏观表征;体积特征可由能够反映土体欠压密程度的孔隙比描述。与非饱和黄土震陷的宏观物理力学机制相适应,粘聚力与内摩擦角主要反映土体的结构性强度(黄土强度特征),孔隙比则反映了土体再固结的潜在性态(黄土沉降量值特征);黄土强度特征对应土体抵御外部载荷的能力,黄土沉降量值特征对应外部载荷作用下的土体沉降能力。更多还原

【Abstract】 Based on the comprehensive analysis of physical process and mechanical mechanism of loess seismic subsidence,the seismic subsidence of unsaturated loess could be described as a consolidation response of generalized solid-phase-media of soil mass under external dynamic loading.The dominant influence factors of loess seismic subsidence should include two aspects,which are the strength and volume characteristics of generalized solid-phase-media of soil mass and external dynamic loading features.The strength characteristic of the media could be figured by the cohesion and internal friction angle,both obtained expediently through laboratory geotechnical tests,while the volume feature of the media could be described by the void ratio.By the view of the macro physical-mechanical mechanism of seismic subsidence in unsaturated loess,the factors of cohesion and internal friction angle briefly represent the characteristics of soil structure strength,and the factor of void ratio influences the final seismic subsidence magnitude of soil mass.In fact,the strength feature of loess shows the endurance capacity of soil mass to resist the external dynamic loading meanwhile,the subsidence magnitude characteristic of loess describes the settlement capacity of soil mass under the external dynamic loading.更多还原