Assessment of Rate Effects in Piezocone Tests from Poroelastic Cavity Expansion Analysis

G. Dienstmann, S. Maghous, F. Schnaid

Article

Soils and Rocks, São Paulo, 41(3): 319-332, September-December, 2018 | PDF


Abstract

Cavity expansion solutions are often used in geomechanics modelling to investigate problems such as the bearing capacity of piles or interpretation of cone and pressuremeter tests. Conceived as a simplified approach to capturing the transient flow effects in the soil around an expanding cylinder, a non-linear poroelastic model is formulated in this paper based on the concept of proportional poroplasticity. The latter is used to assess rate effects and associated drainage conditions during piezocone penetration. In this context, cone tests performed in gold tailings at penetration rates ranging from 0.1 mm/s to 57 mm/s are used to validate the proposed approach. The model predictions are directly compared with in situ testing results in the space of normalized velocity Vh to cone resistance Q and to degree of drainage U, demonstrating the model capability of capturing the transitions from drained to partially drained and undrained soil regimes.


Submitted on March 8, 2018; Final Acceptance on September 18, 2018; Discussion open until April 30, 2019. DOI: 10.28927/SR.413319