An interpretation of consolidation yield stress and upper/lower yield stresses verified with consolidation properties

Consolidation yield stress p_c determined with Casagrande’s method has been treated as an immediate destruction stress of soil skeleton and structure. However, it is an imaginary stress. In log f and log p relationship in connection with Cc*, upper and lower yield stresses p_uy and p_ly exist on the actual consolidation curve, which shows that yielding of soil skeleton occurs gradually. Based on the verification with consolidation properties of alluvial clays, it is considered that the destruction stress coming into contact with the state boundary surface is p_uy rather than p_c.