Correlation of engineering characteristics of Marine Clay from Central West Coast of Malaysia

Abstract

Quaternary erosion induced by climatic and sea level changes have produced widespread and thick deposits of soft marine clays in the coastal areas and major river valleys on the west coast of Malaysia. These areas of poor ground condition have been attracting increasing attention as land reclamation, strengthening of the reclaimed ground and coastal development projects, which have gained momentum in recent years. A study was conducted mainly to establish the geotechnical properties of marine clay from the central west coast region of Malaysia. The data’s are obtained from four completed project sites comprising about 48 nos. of borehole. Correlations and geotechnical parameters are established to assist in the preliminary design process. From the study, it can be concluded that the marine clay from central west coast of Malaysia have high natural moisture content (w) which reaches 125%. Other physical parameters such as liquid limit (wL) is between 50 to 125%, unit weight (?) is in the range of 13 to 18 kN/m3 and the average specific gravity (Gs) is 2.6. The strength parameters are also established; the effective friction angle (f') is in the range of 15 to 25o and the effective cohesion (c') is 2 to 20 kPa. The undrained shear strength obtained from vane shear test shows that the value is ranging from 4 to 65 kPa. Based on the oedometer test, the compressibility parameters have been produced, such as range of void ratio (eo) is 1.5 to 3.0. Range of compressibility index obtained is 0.2 to 1.5 and for compression ratio (CR) is 0.1 to 0.4. The pre consolidation pressure (Pc') is 20 to 125 kPa and for coefficient of volume compressibility (mv) is 0.25 to 1.5m2/MN is also have been established. From the correlation derived, it shows that the undrained shear strength decreases with the increase in natural moisture content and liquidity index. The same trend also found with the effective friction angle where it is decreases with the increase in plasticity index. The correlation for effective cohesion is increases with the increase in liquidity index. From the correlation derived on compressibility parameters, it shows that compressibility index increases with natural moisture content, plasticity index, liquid limit and void ratio, whereas compression ratio is also increases with void ratio and liquid limit.