A computerized statistical curve-fitting algorithm has been developed for determining the time-dependent properties of conventional (load-incremental) consolidation test data. Analytical models of the graphical methods developed by Taylor and Casagrande and of the Naylor-Doran method of successive approximations determtne values for the coefficients of consolidation, permeability, and the values of deflection corresponding to the begimltng and endtng of primary consolidation. The coefficients of volume change and secondary compression are also calculated. A modified statistical definition is used to select the linear portions of the data curves and is applicable to other data-fitting problems. After the Naylor-Doran method has been used, the coefficient of consolidation cy is calculated according to a definition independent of errors in the deflection at the begining of primary consolidation do. Input instructions, codtng sheets, example problems, a flow chart, and source listing are provided. The computer program is in Fortran N for the IBM 370/165 computer and Calcomp 663 drum plotter and has proven to be extremely effective in the analysis of over 30 sets of time-deflection consolidation test data.

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The contents of this report reflect the view of the author who Is responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the Federal Highway Administration, of the Kentucky Bureau of Highways, or of the University of Kentucky. This report does not constitute a standard specification, or regulation.