Advancing Cone Penetration Test Interpretation In Structured Clays With The Particle Finite Element Method (PFEM)

  • Alyamani, Gosai (Newcastle University)
  • Rouainia, Mohamed (Newcastle University)

Please login to view abstract download link

Cone penetration testing (CPTu) is the most widely used in-situ geotechnical test. Interpretation of CPTu tests are often empirical and usually deliver adequate parameters for conventional soils. To improve the accuracy and efficiency of CPTu simulations, researchers are incorporating advanced soil models into numerical tools, conducting validation and calibration studies, and applying the refined understanding of soil behavior to complex geotechnical problems like liquefaction and slope stability analysis. Numerical simulations of cone penetration testing (CPTu) in soft soils have become achievable with the aid of approaches such as the Particle Finite Element Method (PFEM), enabling more realistic representations, specifically adapted for analyzing coupled geotechnical issues. However, interpretation is uncertain in non-standard soils such as structured clays. The Particle Finite Element Method is employed to address the large deformations associated with cone penetration problems to conduct CPTu simulations, while the Modified Structured Cam-Clay Model (MSCC) is utilized to capture the material response of a naturally structured London Clay. Models of this type provide reasonable description of the effect of degradation, crushing of soil cementation structure and the mechanical response of structured clay under strain hardening and softening conditions. The approach for simulating the shear behavior of structured clay is straightforward, similar to other models within the Cam Clay family. This paper will simulate CPTu insertion into London Clay, in which the effect of initial structure and the rate of degradation of structure on CPTu metrics will be explored. Simulation outputs will be used to assess current practice interpretation techniques of CPTu. The hypothesis proposes that the numerical analyses can effectively alleviate uncertainty, leading to an enhanced comprehension of destructuration's influence on the processes and outcomes associated with the CPTu test.