An approach to evaluation of field CPTU dissipation data in overconsolidated fine-grained soils

• Author(s) / Creator(s)

  • Campanella, R.
  • Robertson, P. K.
  • Woeller, D.
  • Sully, J.

• Abstract: Dissipation of excess pore pressures during piezocone testing in firm to stiff overconsolidated fine-grained soils provides data curves that cannot be interpreted using published theoretical solutions. Available solutions are based on either cavity-expansion or strain-path methods, which have been developed for soft, normally consolidated soils and do not adequately model the response in overconsolidated soils. During penetration in overconsolidated soils, large pore-pressure gradients and unloading can exist as the soil moves past the singularity at the cone tip shoulder; these gradients modify the initial pore-pressure distribution around the tip and along the friction sleeve and give rise to nonstandard dissipation curves. The different types of response resulting from the modified pore-pressure distribution are discussed and classified and a correction technique is proposed. In this way, the application of available theoretical models can be used to evaluate in situ flow characteristics. Examples of the different types of pore-pressure response are presented from various sites worldwide.

• Date created

  1999

• Subjects / Keywords

  • Dissipation
  • Consolidation
  • In situ
  • Cone penetration test
  • Overconsolidation ratio
  • Pore pressures
  • Clay

• Type of Item

  Article (Published)

• DOI

  https://doi.org/10.7939/R3W08WH0F

• License

  © 1999 NRC Research Press (Canadian Science Publishing). This version of this article is open access and can be downloaded and shared. The original author(s) and source must be cited.