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博士学位论文摘要 在综述了钙质土的力学性质研究现状的基础上， 指出只有建立与颗粒破坏有关的应力应变理论和强度准则， 才能充分揭示其特殊的物理力学性能， 从而指导基础工程实践。认为钙质土在剪切过程中的剪胀和颗粒破碎的耦合作用是导致其独特的力学与工程性能的根本原因。基于这一思想， 论文从以下几个方面阐述了钙质土的力学特性：（１） 钙质土基本静力学特性。详细讨论了在颗粒破碎和剪胀作用下， 钙质土在压缩、剪切及强度等方面的特征。指出在试验应力水平范围内， 钙质土是稳定材料。（２） 钙质土基本动力学特性。以动三轴试验资料为基础， 叙述了其动三轴应力－应变的影响因素， 并详细研究了动三轴试验条件下孔隙水压力发展模式、变形规律及强度特征。（３） 颗粒破碎对钙质土力学特性的影响。以相对破碎Ｂｒ 为刻画颗粒破碎强弱的指标， 理论推导和实验论证相结合， 导出Ｂｒ与Ｗｐ， （σ′１／σ′３）ｍ ａｘ， （ｑ／ｐ′）ｍ ａｘ， εｓ 等参数之间的显式表达式以及工程上常用的（σ′１／σ′３ ）ｍ ａｘ 与φ′之间的对数线性公式。（４） 钙质土弹塑性本构模型。以沈珠江所建议椭圆屈服面和史－杨角隅式Ｍｏｈｒ－Ｃｏｕｌｏｍ ｂ 准则为基础， 引入颗粒破碎的影响， 建?
Based on the review of the current research status of the mechanical properties of calcareous soil, it is pointed out that only by establishing the stress-strain theory and strength criterion related to particle damage can we fully reveal its special physical and mechanical properties to guide the basic engineering practice. It is believed that the coupling effect of dilatancy and particle breakage of calcareous soil during shearing is the root cause of its unique mechanical and engineering properties. Based on this idea, the paper expounds the mechanical properties of calcareous soil from the following aspects: (1) The basic statics of calcareous soil. The characteristics of calcareous soil in terms of compression, shear and strength are discussed in detail under the action of particle crushing and dilatancy. It is pointed out that calcareous soil is a stable material within the range of experimental stress. (2) Basic kinetic characteristics of calcareous soil. Based on the dynamic triaxial test data, the influencing factors of dynamic triaxial stress-strain are described, and the pore water pressure development model, deformation law and strength characteristics under dynamic triaxial test conditions are studied in detail. (3) The influence of particle crushing on the mechanical properties of calcareous soil. Br and Wp, (σ’1 / σ’3) m ax, (q / p ’) m ax, εs and other parameters were derived from the relative broken Br as the index to describe the strength of broken particles. , And the logarithmically linear formula commonly used between engineering (σ’1 / σ’3) m ax and φ ’. (4) Calcareous soil elastic-plastic constitutive model. Based on the Mohr-Coulom b criterion proposed by Shen Zhujiang for the proposed elliptical yield surface and history - the corner crusher,