Accelerated testing of cement treated singapore marine clay cured under elevated temperature

Abstract

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 of the SDF material to be predicted at a very early curing age (-30hrs). The proposed accelerated curing procedure involves curing the cement mixed clay specimens in a hot water bath at 60 C for 24hrs followed by 6hrs of cooling. Unconfined compression tests and bender element tests are conducted on specimens cured under both the elevated temperature curing condition (30hrs) and the normal room temperature curing condition (7 days and 28 days). Test results show that both the unconfined compressive strength (UCS) and the small-strain shear stiffness (Gmax) are controlled by the water/cement ratio under both curing conditions. Strength-to-strength, stiffness-to-stiffness and strength-to-stiffness correlations are established between the two conditions. The effect of soil type on theses correlations is studied as well. © 2012 American Society of Civil Engineers.