Monotonic loading behavior of calcareous sands with increasing particle crushing

Abstract

Calcareous sediment, comprising higher than 50% calcium carbonate by weight, are mostly located between latitudes 30 ͦ S and 30 ͦ N in coastal areas, such as Florida, India, Puerto Rico, and Australia. Lots of researches have been focused on the loading behavior and the particle breakage subjected to loading. It has been reported that in offshore construction, the measured capacities in calcareous were approximately 20% lower than predicted capacities. Therefore, it is necessary to investigate the loading behavior of calcareous sand with the scenario of post-construction. Calcareous sands from Puerto Rico and Western Australia are selected as the tested materials for this study. The primary objective is to investigate the static loading behavior of calcareous sand with increasing particle crushing. To accomplish this, the physical properties are determined firstly. Calcareous sand is found to have high carbonate content, high specific gravity, and porous particle structures. Triaxial undrained tests are performed with various confining pressures to investigate the static stress-strain behavior of uncrushed calcareous sand. Then, calcareous samples, prepared with different particle crushing contents, are tested by triaxial undrained tests. Various particle crushing contents are obtained by compression loading (one-dimensional consolidation test) and shear loading (triaxial consolidated drained test and TruePath test). The effect of the loading mechanism on particle breakage is evaluated as well. Results obtained from the tests for Puerto Rico and Western Australia sand are analyzed and compared with each other.