Evaluating the compressibility behavior of organic soils using laboratory characterization and rapid on-site piezocone penetration testing Article

cited authors

  • Sobhan, K; Ali, H; Riedy, K; Huynh, H

fiu authors


  • A coordinated field and laboratory investigation was conducted to evaluate the compressibility behavior of organic soils and peat existing under SR 15 / US 98 in Palm Beach County, Florida. Historically, the existence of soft compressible layers under these highways had been the root cause for premature failure leading to costly and frequent repair/reconstruction projects. The objectives of this study were: (i) to conduct Piezocone Penetration Tests (CPTu) along with Porewater Dissipation Experiments (PDE) for in-situ determination of the Coefficient of Consolidation (Cv); (ii) to perform concurrent laboratory consolidation and secondary compression tests to validate the CPTu predicted properties; and (iii) to establish the (Cα/Cc) ratios for Florida organic soils following the well-known Time-Stress-Compressibility concepts. The horizontal Coefficient of Consolidation, Ch (and subsequently the Cv) was predicted from PDE data using several theoretical interpretation models. It was found that a unique relationship exists between Cc and Cα at any stress level, with Cα/Cc ratio ranging between 0.03 and 0.05. Considering the inherent difficulty in sampling and laboratory testing of undisturbed soft organic soils, CPTu holds promise as an effective tool for rapid in-situ characterization of the compressibility parameters, which may be useful for forensic interpretations of rutting-induced failures, and the validation of pavement performance models.

publication date

  • October 1, 2007

Digital Object Identifier (DOI)

start page

  • 9

end page

  • 18


  • 1


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