Accuracy of Carrillo's formula for consolidation of soil with vertical and horizontal drainage under time‐dependent loading

The accuracy of Carrillo's formula for consolidation of soil with vertical and horizontal drainage under time-dependent loading is examined using the rigorous solutions in Zhu and Yin (Geotechnique 2001; 51: 361–367; Geotextiles and Geomembranes 2003) for two situations of free strain and equal strain assumptions. It is found from the examination that Carrillo's formula normally overestimates the overall average degree of consolidation. However, for the ranges of practical significance, the overestimate is less than 3% if the construction time factor Tc is less than 1.25. For the Tc up to 4, the overestimate is less than 9%. The comparison of free strain and equal strain solutions also shows that the difference between the two solutions under time-dependent loading is small. Copyright © 2004 John Wiley & Sons, Ltd.