Residual soil development on sedimentary rocks of the Jurong Formation in Singapore

The Jurong Formation constitutes a variable siliciclastic succession which produces residual soils of differing character. Details of the variability of particle size distribution and plasticity characteristics within the profiles of these residual soils are presented. This variability has considerable implications for strength, permeability and compressibility characteristics. Some results of in situ penetration tests confirm this variability with depth. Details are also provided of the properties of a thin zone apparently intermediate between completely weathered rock and residual soil. This zone is believed to be an important factor in slope instability in some areas