| dc.description.abstract | To improve soil properties with cement, we may add a small amount of cement to enhance the workability and suitability of soil. A lot of researches had been conducted with cyclic triaxial tests, CU tests, and adding different types of coagulant in the past. However, research about time dependency of dilatancy is rare. In this study, the relative experiments were performed for analysis and discussion.
In the static triaxial tests (CU test) of cement treated sand, the shear strength was improved. Then, to understand the development of excess pore water pressure with time, we performed a series of static triaxial creep tests. The test results showed that adding cement can decrease the development of excess pore water pressure. Use these experimental data to draw graphics, then a set of equations of dilatancy coefficient with time for different cement contents were obtained. Through these equations, the excess pore water pressure of cement treated sand applying a constant axial load for a long period can be obtained. Then, performed a series of step loading static triaxial tests, and compared the test results with the calculated values, and good consistency was obtained. The equations can be used as a practical estimation of excess pore water pressure with time. Finally, a cyclic triaxial test was performed to compare with the development of excess pore water pressure of static triaxial test (CU test). Negative values of excess pore water pressure were found in a rapid loading.
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