SOLIDIFICATION AND CONSOLIDATION OF A LIQUEFIED SAND COLUMN.

Abstract

Saturated sandy soils have been observed to liquefy during earthquakes and in laboratory experiments. Following liquefaction the soil grains settle out, and the material solidifies from the base up. The history of pore pressure in a solidifying liquefied sand has been obtained in centrifuge experiments. It is found that the excess pore pressure lags the pore pressure decay which would be expected from the solidification of a mass of rigid grains. Consequently the accreting solid sand layer is consolidating with time during and following accretion. A mathematical description of this process is given by an adaptation of Gibson's (1958) theory of consolidation of a sedimenting clay layer. The resulting theory is compared with experimental centrifuge results, and found to give a satisfactory description of the observations.