Centrifuge Shake Table Tests on the Liquefaction Resistance of Sand with Clayey Fines

Abstract

A series of centrifuge shake table tests were carried out to investigate liquefaction resistance of sand deposits with different fines content. The effects of clayey fines on the generation and dissipation of excess pore water pressure, acceleration record, surface settlement, and stress-strain behavior were investigated. It was found that for the same initial relative density, liquefaction resistance increased as fines content increased from 0% to 10% and then decreased with a further increase in fines content from 10% to 20% in the centrifuge tests. For all tests, a reduced acceleration within the soil was observed after a certain number of cycles due to the onset of liquefaction. Dilative tendencies are different for all tests, but the sand with 10% clay test showed the most obvious dilative behavior during the cyclic mobility stage. The total ground surface settlement and the time for a complete dissipation of excess pore water pressure increased with increasing fines content. Shear strains in the sand deposits increased as the clay content increased from 0% to 20%. Moreover, cone penetration tests were performed before and after shaking to study the effect of fines on penetration resistance. At the same depth across all tests, the penetration resistance before shaking decreased with increasing clay content. However, the penetration resistance after shaking increased with increasing clay content from 0% to 10% and then decreased with increasing clay content from 10% to 20%. When compared with the before-shaking profile, the percentage change in penetration resistance after shaking increased with clay content at the same depth.