The effect of sodium polyacrylate gel on the properties of liquefiable sandy soil under seismic condition

Résumé fourni par la source

Natural soil deposits may be subjected to the liquefaction phenomenon under critical factors in the case of fine grained sandy or silty non-cohesive liquefiable soils, in partially or fully saturated conditions below ground water level and dynamic load. This creates harmful effects on structures due to excessive settlement and loss of bearing capacity. In this study, the use of high capacity water absorbent sodium polyacrylate chemical is proposed as a unique solution, which turns into a gel form by absorbing the pore water of soil. However, sodium polyacrylate releases absorbed water when it is subjected to loading procedure. For this reason, a 25% dry cement additive (0.2% in gel formation) is obtained as a limit value of sealing by weight of polyacrylate in a dry state. First of all, the liquefaction potential of a used poorly-graded soil specimen is proved within a scaled experimental laboratory setup. Next, fundamental geotechnical experiments are carried out by adding sodium polyacrylate in different proportions to liquefiable silica sand to enhance properties in terms of specific gravity, permeability, consolidation, swelling potential and parameters of shear strength according to experimental results. As a result, a sodium polyacrylate-cement mixture will provide serious advantages in terms of the geotechnical parameters of liquefiable soils. • A high capacity water absorbent sodium polyacrylate is used inside silica sand. • Chemical agent is mixed with soil at rates of 2.5 %, 5 %, 7.5 % and 10 %. • The changes in main geotechnical properties of liquefiable sand are presented. • A high level of pressure is observed up to 6.3 kg/cm 2 with 940% swelling potential. • A trace amount of cement (0.2%) should be added into gel to provide the sealing.

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