The Influence of Stress Level on the Shear Strength of Rockfill Materials

Shear strength of rockfill materials depends on stress level and wetting. The scope of this paper is to investigate the effect of these factors on the behavior of rockfill materials. For this purpose, a series of medium-scale direct shear tests (30x30x15 cm) are conducted on dry and saturated specimens of a rockfill material, in five normal stress levels. The test results show non-linear shear strength envelope. Therefore, Mohr-Coulomb linear criterion is inappropriate for predicting the behavior of such materials. Also, gradation of the materials before and after test illustrates the effect of stress level and saturation on the amount of particle breakage.

Keywords:

Direct Shear Test , Rockfill , Shear Strength , Stress Level , Saturation.