Loess has a unique structure that makes it susceptible to liquefaction during intense seismic activity. Liquefaction is closely linked to microstructural changes due to hydraulic coupling. This study examined the threedimensional microstructure evolution of loess in various liquefaction states using dynamic triaxial tests and high-precision micrometer CT scanning. As the ratio of pore water pressure (Rwp) increases, the size of loess particles tends to decrease while the roundness is inclined to increase. Moreover, the morphology and orientation of particles remain relatively stable under such circumstances. In addition, increasing Rwp will decrease the number of macropores, increase the number of mesopores and fine-pores, and decrease the size of throats and channel length, with which petite throats and pores become more prominent. Consequently, liquefaction gradually opens closed pores, enhances soil connectivity, and divides large pores to increase small to mediumsized pores, improving pore distribution uniformity. Liquefaction induces the pore shape coefficient to decrease, the number of slim pores to increase, and irregular and circular pores to decrease. These findings provide a scientific foundation for preventing and evaluating loess liquefaction disasters and shed light on the microscopic mechanisms of loess liquefaction.

来源平台：SOIL DYNAMICS AND EARTHQUAKE ENGINEERING