Cement stabilized Singapore marine clay is the material associated with the Stabilized Dredged Fill (SDF) technology practiced in Singapore. A novel accelerated curing/testing procedure is proposed in this study making use of a constant temperature hot water bath. The accelerated testing technique enables the later-age strength (7-day strength in this study) of the SDF material to be forecasted at a very early curing age (～30 hrs). Laboratory samples are prepared by mixing Singapore upper marine clay at high water content with Portland blast furnace cement. The mixes are designed to reflect the actual constituent proportions on the site. Samples are cured in a hot water bath at 60 °C for 24 hrs followed by 6 hrs of cooling. Unconfined compression tests and bender element tests are conducted on specimens cured under both accelerated condition (30 hrs) and normal room temperature condition (7 days). Test results show that both the unconfined compressive strength (UCS) and the small-strain shear stiffness (G_(max)) are controlled by the water/cement ratio in either curing condition. Accelerated UCS after 30 hrs of curing can be used to predict 7-day UCS, although it may over-predict by 20%. In addition to the strength-to-strength correlation, stiffness-to-stiffness and strength-to-stiffness correlations are also established between the two conditions. As effective quality control requires early determination of the material later-age strength, these correlations may be used to improve the current SDF quality control.
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