POROSITY DEPENDENCY ON MECHANICAL PROPERTIES AND PORE-WATER PRESSURE RESPONSE OF SANDSTONE IN TRIAXIAL COMPRESSION

摘要

Undrained triaxial tests performed on sandstone specimens with two different porosities showed that the observed induced pore-water pressure response is quicker in high porous sandstone and the maximum observed induced pore-water pressure is higher compared to that of low porous sandstone.Volumetric strain results showed that the dilation is a significant mechanism only at low confining pressures for both types of sandstone.Within the tested confining pressure range,a considerable difference in the onset of dilatancy relative to the peak differential axial stress was not observed.