Effect of Total Stress Path and Gas Volume Change on Undrained Shear Strength of Gassy Clay

Clay with free gas bubbles can be frequently encountered in the seabed. Gassy clay is an unsaturated soil, but its mechanical behavior cannot described using conventional soil mechanics because it has a composite internal structure saturated matrix and bubbles. The have either detrimental or beneficial effect on undrained shear strength of clay. New lower upper bounds for gassy are derived by considering total stress path plastic hardening matrix. For bound, assumed that there only bubble flooding, sample same as Bubble flooding makes partially drained increases strength. amount calculated modified Cam-Clay model Boyle's law ideal gas. bound based assumption entire fails without cavity size evolves due to Compared Wheeler's do not consider matrix, new theoretical results give better prediction clays, especially bound. Implications constitutive modeling discussed research outcomes.