Deformation characteristics of kaolinite clay with different initial water #br#
contents in NaCl solution
Yu Haihao1 Sun Dean2 Yu Mingbo3 Jiang Shiqing3
1. Laboratory of Geomechnics and Geotechnical Engineering, Guilin University of Technology, Guilin 541004, China;
2. Shanghai University, Shanghai 200444, China; 3. Guilin Institute of Geological Engineering Investigation,
China National Building Material Group, Guilin 541004, China
Abstract:The mechanical behavior of clays is strongly affected by the pore structure state and pore fluid composition. The aim of this paper is to investigate the effects of initial water content and NaCl solution on the volume change behavior of kaolinite clay. In this study, numbers of kaolin specimens with different initial water contents were exposed to different concentrations of NaCl solution in the wetting test. And then these specimens were compressed in oedometer. The results of nuclear magnetic resonance (NMR) tests on the specimens after wetting tests showed that the pore water of the swelled specimens existed in two ways. One way is the adsorbed water on the surface of particles that was affected by the diffuse double layers. After exposing to NaCl solution, the effective stresses decreases with increasing in the degree of saturation. Because of the diffuse double layers on the particle surface, there was generalized-osmotic pressure in the specimens. The generalized-osmotic pressure decreases with increasing the concentration of NaCl solution, which results in a decrease in swelling strain. At the same compactive effort, the soil fabric becomes increasingly oriented with an increase in water content which it results the pore-size less than 0.01μm increasing. The pore-size less than 0.01μm is hard to be compressed.
于海浩 孙德安 于明波 蒋仕清. NaCl溶液中不同含水率高岭土的变形特性[J]. 土木工程学报, 2019, 52(S2): 14-22.
Yu Haihao Sun Dean Yu Mingbo Jiang Shiqing. Deformation characteristics of kaolinite clay with different initial water #br#
contents in NaCl solution. 土木工程学报, 2019, 52(S2): 14-22.