End-of-primary consolidation parameters using inflection point method

This note describes a faster and complete consolidation testing procedure using the inflection point method so as to obtain the void ratio–consolidation curve at the end-of-primary consolidation and the coefficient of consolidation. The testing procedure is similar to the conventional incremental load consolidation test, with the only difference being that the subsequent loading is applied once the degree of consolidation of U = 70·15% is reached. The time and settlement corresponding to U = 70·15% is obtained using the inflection point method, from which the end-of-primary consolidation and the coefficient of consolidation are evaluated. The validity of the proposed procedure is verified by performing tests on four reconstituted and three undisturbed soil samples. By adopting the proposed procedure, complete consolidation tests can be completed within 2·5 to 9 h depending on the coefficient of consolidation of the soils.