Effect of different parameters on cyclic triaxial response of biopolymer treated soil

Abstract

Generally, silty sand possesses very negligible cohesion and may fail under dynamic loading due to liquefaction. To mitigate liquefaction, treatment using biopolymers are now becoming popular. In the current study, liquefaction mitigation using agar biopolymer has been studied in detail. The effect of treatment parameters like agar content (0%, 0.5%, 1%, 2% and 3%) and curing period (1 day, 3 days, 7 days, 28 days and 1 year) have been studied and the effect of loading condition by varying the over consolidation ratio (1, 2, 3 and 4) were investigated by performing a series of consolidated undrained cyclic triaxial tests. The test results were analyzed to study the influence on pore water pressure, cyclic stress path behaviour and hysteresis response. It was seen that the excess pore pressure buildup was reduced with an increase in agar dosage and an increase in OCR. However, it increased with an increase in the curing period, though the maximum excess pore pressure ratio after 50 loading cycles was just 0.7 after 1 year of curing. The stiffness of the soil increased with an increase in agar content, curing period and OCR, as indicated by the higher inclination of the hysteresis loops.