Effect of non-plastic Fc on cyclic and monotonic shear strength of sand–silt mixtures

This paper details a laboratory investigation into how non-plastic fines content influences the monotonic and cyclic liquefaction potential of sandy soil samples. The study involved conducting monotonic and cyclic triaxial tests on reconstituted saturated sand samples with fines content varying from 0 to 25% for the monotonic tests and from 0 to 20% for the cyclic tests. All tests were performed under a confining pressure of 100 kPa and with a relative density of 65%. This paper is divided into two sections. The first section describes the properties of the soils used in the study, while the second section analyzes how non-plastic fines content affects the monotonic and cyclic behavior of sand-silt mixtures. The results from the monotonic tests show that the liquefaction potential of the mixtures decreases as the fines content increases. The results of the cyclic tests indicate that higher fines content accelerates the liquefaction process at the tested amplitudes, while the liquefaction resistance decreases as the loading amplitude increases. The reduction in liquefaction resistance for Rass sand-silt mixtures is notably significant at lower cyclic stress ratios, cyclic stress ratio (CSR) = 0.15 and 0.25.