Siti Norafida Jusoh

PERFORMANCE OF LIME-TREATED MARINE CLAY ON STRENGTH AND COMPRESSIBILITY CHRACTERISTICS

The presence of marine clay in Iskandar Malaysia Region, Nusajaya has caused expensive solutions in the construction of structures and roads. Alternatively, soil treatment is suggested to increase the strength of the unsuitable material to meet the constructions requirement for foundation and also to achieve the specifications for development work. In this study, a series of laboratory test has been conducted to determine the potential of lime to stabilize marine clay to form the basis of a strong, reliable land for construction of roads and building. Testing program involves obtaining specimens of marine clays from various locations at Iskandar Malaysia Region, followed by laboratory tests to determine the physical and engineering properties with and without the addition of lime. The proportions of hydrated lime added are 3%, 6% and 9% to the untreated marine clay and tested at 7 and 28 days curing periods. Results show an increase in strength with increasing lime content. In addition, strength also increases significantly as early as 7 curing days and continues for 28 curing days. In agreement with the strength tests, compression characteristics improved with increasing lime content and as time prolonged. Hence, lime is successful and considered effective to improve the strength and compressibility behavior of Marine clay.

CYCLIC BEHAVIOUR OF JOHOR SAND

Series of laboratory testing on the investigation of soil liquefaction using cyclic triaxial test had been carried out by researchers around the world but many of the results are contradictory. Thus, it is important to first determine the condition in which the clean sand is most susceptible to liquefaction, then only the liquefaction susceptibility of sand matrix soils could be compared and discussed under this specific condition. This paper presents the undrained behaviour of Johor sand and sand mixed with fines (kaolin) from cyclic triaxial tests. Stress controlled triaxial test apparatus was used to shear the isotropically consolidated soil samples under undrained two-way cyclic loading until the initiation of liquefaction. The liquefaction was defined based on: (i) excess pore pressure was equal to effective confining pressure or (ii) double amplitude strain of 5 % was reached, whichever was achieved first. The results of two-way cyclic triaxial tests on clean sand showed that besides the cyclic stress ratio, the liquefaction resistance of the sand under undrained loading was proportional to effective consolidation pressure and density index. The Johor sand was more liquefiable at its loose state and under low effective consolidation pressure, when subjected to earthquake loading.