Arrested compression tests on two types of sand

Abstract

Silica sand and quartz sand were subjected to uniaxial loading and unloading at rates of 0.1/s and 0.0001/s. The particle size distribution was measured, and found to be significantly altered when peak strains were 10% or greater. The loading modulus for silica sand was bilinear, and suggestive of elastic-plastic behavior, where the plastic part is due to void closure. On unloading, the modulus is close to the loading “elastic” value. Coral sand is softer than silica sand on loading, and the modulus is almost constant and much less than for silica sand. Both types of sand are recovered with a higher density than can be obtained with the starting particle mix. This suggests particles have crushed and filled some of the voids. Indeed, reduction of mean particle size is verified from post-test analysis. Coral sand, which has the greater reduction in void content, also exhibits increased particle breakup.