Freeze dehydration and mercury intrusion porosimetry was used to study the change of pore size distribution of a structured soft soil
during one-dimension compression. It was found that when pressure increased beyond the structure yield stress
the largest pores began to break down. If the pressure was increased continuously
smaller pores would be affected; but the intra-aggregate pores could not be changed during compression. Pore structure breakage potential was defined in terms of the evolution of the pore size distribution in different stress level.