A STUDY OF QUICKSAND PHENOMENON

Abstract

Quicksand is a unique condition of the soil when it loses its bearing capacity and stability due to upward seepage pressure. This is one of the most treacherous situ-ations which can be met by a field engineer. The theory and reasons for the occurrence of quicksand and remedies and pre-cautions to cope with this ghastly trap have been enumerated. The details of a portable Quicksand Tank designed and fabricated, as a part of this study, have been described. Following experimental test results are included: (i) Determination of critical hydraulic gradient for a soil at different void ratios and comparison with theoretical values. (ii.) Determination of critical hydraulic head for dif- ferent submerged unit weights of soil and different depths of penetration of sheeting in case of a single row of sheet pile and comparison with theoretical values.. The results are useful for the physical understand-ing of quicksand phenomenon., These results can be applied for the design of a single row of sheet pile cofferdams and deep excavations below water table in soils, susceptible to "quicksand" condition. The results presented in the form of curves will be a ready reference for the field engineers to check safety against quicksand condition.