Calcareous silts are encountered in many offshore areas where oil and gas exploitations are taking place (e.g., Arabian gulf, south east of Brazil, south east and north west of Australia). Understanding behavior of calcareous silts remains challenging as undisturbed silt samples are difficult to obtain, and most studies rely on remoulded silt samples. The purpose of this paper is to characterize the mechanical behavior of intact and remoulded offshore calcareous silts from two different water depths. The comparisons are done based on microstructure characterization using scanning electron microscopy (SEM) images supported by index tests, one-dimensional compression tests and undrained monotonic triaxial tests. The results have shown that, except for the critical state friction angle, the behaviour of remoulded silts differs from that of intact silts, due to the change in microstructure, which appears to be more compact with less intact open shell particles.
