Deformation mechanism and constitutive relation of soft soils

A microstructural catastrophic model was achieved by adopting bifurcation theory and catastrophe theory. Moreover, a constitutive relation was established based on this model and creep equation. Theoretical analyzing shows that the model seems to capture well the observed features of soft clay compression behavior. During the compression, it is only the largest existing pores that collapse under a given effective pressure. The smaller the pores are, the larger the pressure is required. When the stress grows, it is the pores collapsing caused deformation that domain, while when the stress is stable, the creep deformation accounts for the majority of the total.