GEOTECHNICAL PROPERTIES OF WEAK SANDSTONES

Weak sandstones are here defined as having a saturated uniaxial compression strength of 0. 5-20 MPa. The mineralogy, texture, density, porosity and saturated moisture content of these materials have been studied together with their permeability, strength and deformability. Microscopic characters, in particular mineral composition, packing density, area of grain contact and grain size distribution, were successfully used to explain the strength, deformability and permeability of weak sandstones. A practical index parameter for assessing the strength and deformability of weak sandstones has been developed.