Abstract

Accurate prediction of the rate of consolidation settlement is dependent upon a reliable method of determining the coefficient of consolidation (cv) and the time to end of primary consolidation of the natural soil. For this purpose, and to circumvent errors associated with graphical procedures in evaluating cv, a FORTRAN program was developed to determine the best fit of laboratory consolidation test data using a combination of a probabilistic method and a minimization of the sum of squared residual (SSR) method. The proposed computer procedure does not use any particular point on the time-settlement curve. The program uses ranges of probable values of d0, d100, and cv. For each set of values d0, d100, and cv selected in a random manner, the SSR is computed. The set of values with the smallest SSR is considered as the best fit. This procedure leads to suitable reference values of the coefficient of consolidation and the end of primary consolidation, and permits an assessment of the accuracy of classical graphical log(t) and t1/2 procedures.

Issue Section:
Technical Notes
Keywords:
consolidation coefficient, primary consolidation, probabilistic, least squares, log of time method, square root of time method

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