Uniaxial Compressive Mechanical Properties of Fissured Loess after Dry-Wet Cycles

Uniaxial compression tests on fissured loess after dry-wet cycles were carried out systematically, and the fissure evolution pattern and mechanical properties of fissured loess were deeply investigated. The results show that the surface crack rate R_sc and fractal dimension D_f of samples with different angles increase after more dry-wet cycles, while the growth rate gradually slows down. The dry-wet cycling has no significant influence on the types and characteristics of stress-strain curves; the initial slope of the stress-strain curve declines with the increase of dry-wet cycles. The stress-strain curves of loess samples with different angles all show the characteristics of strain softening, and the samples with 45° show bimodal characteristics. In addition, the uniaxial compression strength of samples with different angles exhibits decelerated attenuation with growing dry-wet cycles. The relationship between uniaxial compression strength and fissure angle unanimously presents characteristics of “double valley” after different dry-wet cycles.