Liquefaction behavior of reinforced saturated sand under dynamic conditions

Abstract

For reduction in liquefaction potential in liquefiable soils, the common practices are densification of strata, draining, vibroflotation, etc. For densification, the deployment of large plant and machinery is involved. Reinforced earth techniques may simplify the densification technique. The behavior of reinforced soil is well known. In the present paper, efforts had been made to see the effect of reinforcement against liquefaction. Uniaxial geogrid had been used to reinforce the fine sand. Tests had been conducted on the shake table at different accelerations varying from 0·1 to 0·3g. For particular value of acceleration, the densities of the sample were also varied from 35 to 65%. It was observed that after inclusion of 4 Nos. geogrid layers, the reduction in liquefaction potential was 17–20% at different values of acceleration on 35% density. At higher densities, the average increase in liquefaction resistance was 25%. Effect of surcharge was also studied on reinforced sand to simulate field conditions. For surcharge conditions at 50–65% densities, it is observed that average liquefaction resistance increased 28–45% at 0·3g for reinforced soil.