ABSTRACT
Weathered granite, sedimentary and metamorphic rocks are the main types of residual soil in Malaysia. In natural state the soil above ground water level are in unsaturated condition. Major parts of residual soils in Malaysia are in unsaturated state, therefore studies have to be done in order to understand the influence of soil suction on shear strength of these residual soils. Soil suction has important influences on water entry, structural stability, stiffness, shear strength and volume change, which are an important variables in soil engineering design.
Shear strength determination was carried out on unsaturated sample using specially modified apparatus. At the same time the concept of multistage multi suction is implemented in order to eliminate soil variations. Discussion in the paper covers the modification of testing equipment, method of sample collection, details of multi stage test procedure and test results.
