A method for estimating consolidation parameters from primary consolidation

We have already proposed the constitutive equation for one-dimensional consolidation analysis that accounts for secondary compression. To calculate the secondary consolidation from the primary consolidation, the proposed model requires the compression index C(c)(*) and the coefficient of consolidation C(v)(*). defined by the primary consolidation, which are not available from consolidation test results. Therefore, these constants are determined by trial and error until a match is obtained with the consolidation-time curve from the consolidation test. This study investigated an easier method for estimating C(c)(*) and C(v)(*), by first attempting to use the primary consolidation ratio r, calculated by the standard consolidation test, because the ratio of C(c)(*) to C(c) indicates the ratio of primary consolidation to the total settlement. The method of square root of time was then devised, using t(50) instead of t(90). By applying these methods to undisturbed and reconstituted clays with different properties, it was found that both methods are capable of reproducing consolidation-time curves without significant differences from the conventional trial and error method.