摘要
基于冻土单轴压缩的 CT动态测试 ,提出冻土单轴压缩下的损伤由完全不同的两个阶段组成 :其一是塑性硬化下的塑性损伤 ,其二是由于新产生的裂隙造成的微裂纹损伤 .对两种不同损伤阶段下冻土微结构变化特征进行了讨论 ,给出了各阶段损伤量计算公式 .采用该方法分别对饱水冻土试样和未饱水冻土试样的损伤量进行了计算 ,得到了塑性损伤和微裂纹损伤阶段的损伤量及总附加损伤量 .得出饱水冻土的塑性损伤和微裂纹损伤产生的应变条件门槛值分别为 0 .75 %和 5 .0 % ,未饱水冻土的分别为 0 .70 %和 4.5 % .
Based on timely CT experimental investigation of uni axial compression, the damage process of the frozen reconstructed soil is separated into two stages. The first stage is the plastic damage, the second one is micro crack damage. Variation of micro structure traits of the frozen soil under each stage was discussed, measurement methods for different kinds of damage were established. After that, for the saturated frozen soil, 0.75% and 5.0% are declared as the critical condition strain values to the plastic damage and micro crack damage respectively, 0.70% and 4.5% for that of unsaturated frozen soil. In the conclusion, the damage values of the saturated and the unsaturated frozen soil under each stage were judged.
出处
《大连理工大学学报》
CAS
CSCD
北大核心
2002年第2期223-227,共5页
Journal of Dalian University of Technology
基金
中国科学院兰州寒区旱区环境与工程研究所冻土工程国家重点实验室资助项目 (980 1)
