Evolution of K0 Coefficient and Deformation Parameters of Coral Sand Under K0 Consolidation

In the design of geotechnical engineering, the coefficient of earth pressure at rest, denoted by K0, is one of the commonly used parameters. Nonlinear elastic models and their deformation parameters are widely used because of their simplicity and practicality. Coral sand is also increasingly used as backfill or foundation material for marine geotechnical engineering. This study performed a series of K0 consolidation tests on coral sand to investigate the evolution of K0 and deformation parameters. The K0 values of coral sands were measured and their relative breakage index was evaluated. The deformation parameters were calculated based on the test results and generalized Hooke's law. The results show that K0 value decreases with increasing the effective axial stress and initial relative density, and the relative breakage index increases with the increase of the mean effective stress. The tangent Poisson's ratio decreases as the effective axial stress and initial relative density increase. On the contrary, the tangent elastic modulus increases as the effective axial stress and initial relative density increase. An empirical formula of K0 and the range of values of deformation parameters are proposed based on the test results. The stress–strain relationship of coral sand under K0 consolidation is reasonably predicted by the nonlinear elastic model.