Experimental study on the liquefaction resistance of sand–clay mixtures: Effect of clay content and grading characteristics

Abstract

ABSTRACTThis paper presents a laboratory study of the influence of clay content and grading characteristics on the liquefaction resistance of sand–clay mixtures. The study is performed using a triaxial apparatus on reconstituted sand–clay mixtures containing a low clay content ranging from 0 to 20%. The tests were performed on samples at a relative density of 73% under an initial confining pressure of 100 kPa. The results of this study indicate that the undrained shear strength (liquefaction resistance) of sand–clay mixtures is controlled by the percentage of clay fraction and grading characteristics of sand–clay mixtures. However, the results show that the increase in the clay content up to 15% reduces the resistance to liquefaction of the sand–clay mixtures. Also, the test results indicate that the undrained shear strength at the peak and the undrained residual strength and the maximal shear strength decrease with the increase in clay content. Indeed, they decrease with an increase in the uniformity coefficient and the coefficient of gradation, also it was found that they decrease with a decrease in the effective diameter and the mean particle diameter.