Test study on residual soil under special stress paths

Some mechanical properties of granite residual soil were studied under special stress paths using advanced GDS stress path triaxial apparatus. The triaxial drained shear tests were conducted under two types of stress paths. The first set of tests was that mean stress p was constant while deviator stress q changed; the second set of tests was that q was constant while p changed. The test results show that the deviator stress-axial strain curve is hyperbola for the first set of tests; however, the mean stress-axial strain curve is power function for the second set of tests. The granite residual soil has shear shrinkage property. The rebound bulk modulus increases notably with deviator stress.