EVOLUTION OF THE PORE CHARACTERISTICS OF RED CLAY UNDER AXIAL STRAIN

摘要

To study the evolution of pore structure in red clay during triaxial shear, nuclear magnetic resonance tests were performed on soil samples to determine their pore characteristics after undergoing different shear strains during triaxial consolidated undrained shear tests under different confining pressures. The results showed that the effects of confining pressure and shear on the intragranular pores of the soil samples were minimal. In contrast, during consolidation and triaxial shear, interparticle macropores in the soil sample were compressed. Generally, the greater the confining pressure during the test, the faster the soil structure stabilized. Once the axial strain exceeded 8%, the soil structure also stabilized, and both deviatoric stress and pore diameter remained unchanged. Evolution of the pore characteristics during triaxial shear revealed that their shear deformation history determined the new microstructure of the saturated compacted red clay.