Shear Strength of Surface-Mine Spoils Measured by Triaxial and Direct Shear Methods

摘要

Results of measurements of several surface-mine spoils by triaxial and direct shear methods indicated that the direct shear method may be used for evaluating the shear strength parameters of surface-mine spoils. The average angle of internal friction determined by direct shear testing was 38.6 degrees; the average value for the triaxial method was 33.4 degrees. The average value of cohesion determined by direct shear testing of dry materials was .077 bar; the average value of cohesion determined for the triaxial method was .100 bar. Soaking specimens immediately before direct shear testing reduced the average angle of internal friction by 8.2 degrees: there was no significant change in cohesion.