Crack Evolution Characteristics and Cracking Mechanism of Red Beds in Central Sichuan during Seepage and Swelling

Crack is one of the important factors affecting engineering characteristics expansive rock and soil. In order to study evolution cracking mechanism red beds in Central Sichuan during seepage swelling, multiple groups tests are conducted under different initial states with a self-made device. addition, combining swelling-softening numerical analysis, swelling-cracking studied. The following research results obtained. (1) process swelling cracks divided into three stages: generation stage, rapid development stabilization stage. increase crack degree accounts for 90% whole process. (2) final sample related water content, absorption method, clay mineral content. lower greater sample. soaking method than that capillary mudstone argillaceous sandstone sandstone. (3) controlled by significant values absorption, which w 1 , id="M2"> 2 id="M3"> 3 respectively, representing beginning cracking, starting Among them, id="M4"> great significance practice. It shows has entered stage development, this will exponentially absorption. (4) Uneven uneven distribution minerals lead rock, turn generates stress. Under combined action stress swelling-softening, internal structure destroyed, leading cracks. Due causes expansion, mechanical shape resulting be different.