Damage dissipation potential of frozen remolded Lanzhou loess based on CT uniaxial compression test results
ZHAO Shu-ping1, MA Wei1, ZHENG Jian-feng1, JIAO Gui-de12
1. State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; 2. Civil and Engineering Department, Lanzhou University, Lanzhou 730000, China
Abstract：The physical nature of frozen soil damage is analyzed. A series of CT scanning during the uniaxial compress test process is conducted on an enhanced triaxial system which works together with the CT system. According to the test results, the yield strain, damage strain critical value, and failure strain critical value of the frozen remolded Lanzhou loess are obtained. Then, the plastic strain is used to describe the damage threshold value. The lower the temperature, the larger the damage threshold value. In the end, the CT value is used to define damage variable, and the damage evolution law is derived based on the results of CT scanning tests. A damage potential function suitable for frozen soil is proposed.
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