RESIDUAL DEFORMATION CHARACTERISTICS OF CORAL SAND UNDER CYCLIC COMPRESSIVE LOADING IN OEDOMETER TESTS

Abstract

This article presents an experimental study on the residual deformation characteristics of coral sand under cyclic compressive loading in oedometer tests. The tests were carried out on specimens with relative densities (Dr = 30%, 50%, and 70%) subjected to three loading-unloading cycles with vertical stresses reaching up to 400 kPa. The results demonstrate that residual deformation accounts for a large proportion of the total deformation, approximately 80%, and tends to accumulate with increasing loading cycles. The deformation behavior is also strongly influenced by relative density; as the relative density increases, the total deformation decreases, while the irreversible nature of the material remains significant. Notably, the rate of residual deformation accumulation gradually decreases with increasing loading cycles, reflecting the densification and rearrangement of the particle skeleton. These findings contribute to a better understanding of the cyclic behavior of coral sand and provide a scientific basis for further studies and constitutive modeling.