A study of the loading rate effect on disturbed loess

In order to reveal the impact of deformation and mechanical characteristics of disturbed loess at different loading rates on engineering practice, the loading rate effect of disturbed loess under different conditions are analyzed in this paper by conducting triaxial shear tests of four loading rates under different confining pressures and water content. The difference between the results for disturbed loess and undisturbed loess is discussed based on soil structure. The rule of influence of loading rates on the deformation and mechanical characteristics is obtained. The stress-strain curves show the strain hardening at all the loading rates. There is a critical loading rate in the influence of loading rate on the fracture strength. The fracture strength increases with the increasing loading rate when the loading rate is less than the critical value, but decreases with the increasing loading rate when it exceeds the critical value. With the increasing loading rate, the cohesion c and shear strength have the same rule and critical loading rate, but the friction angle φ decreases slightly.