干湿循环作用下镉污染红黏土的变形及强度特征.

Red clay in Lijiang River basin of Guilin with different cadmium ion concentrations subjected to dry-wet cycles at 40 °C is taken as the research object in this paper. Triaxial test is conducted to study the effects of cadmium pollution and dry-wet cycles on the deformation and shear strength characteristics of red clay. The results show that the horizontal shrinkage rate, vertical shrinkage rate and volume shrinkage rate of red clay is increased with time in an “S” shaped curve under different cadmium concentrations. The peak shear stress of red clay is increased with dry-wet cycles under different cadmium concentrations. With the increasing of dry-wet cycles, the cohesive force of cadmium-contaminated red clay tends to increase first and then decreases. Cadmium finishes its damage to the structure of red clay before the dry-wet cycles, so that the internal friction angle reaches the limit value, and the more increased of cadmium concentration, the more obvious the mechanical characteristics of the damage. [ABSTRACT FROM AUTHOR]