KSCE Journal of Civil Engineering

, Volume 23, Issue 9, pp 3818–3830 | Cite as

Critical Reappraisal of Casagrande and Taylor Methods for Coefficient of Consolidation

  • Bartłomiej Szczepan OlekEmail author
Geotechnical Engineering


Conventionally the experimental time-settlement data from an oedometer test are analyzed by standard curve-fitting methods, Casagrande’s log t method and Taylor’s root t method. This allows determination of the end of primary consolidation parameters, (EOP) as well as coefficient of consolidation, cv. Mentioned methods use both the initial and later part of the consolidation curve and are influenced by initial and secondary consolidation effects. In this study, the settlement-time data gathered from conventional oedometer tests conducted on various cohesive soils were analyzed. To assess the validity of each cv value, the experimental results were compared with the theoretical degree of consolidation curve and quantified using the scalar error function. The predictive ability of the Terzaghi consolidation model is also discussed. Based on the comparative study it has been revealed that Casagrande and Taylor methods are insufficient to correctly determine the consolidation parameters.


consolidation primary consolidation clays parameter optimization soil behavior coefficient of consolidation 


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© Korean Society of Civil Engineers 2019

Authors and Affiliations

  1. 1.Dept. of Structural MechanicsCracow University of TechnologyKrakowPoland

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