An approach to evaluate internal friction angle from dynamic penetration tests

摘要

This paper presents an approach to predict the internal friction angle of cohesionless soils from dynamic penetration tests. The proposed methodology allies the dimensional equation technique (Π numbers) with a numerical simulation routine that is able to reproduce the dynamic test response for a SPT or for any other dynamically driven device such as LPT (Lobo, 2007). The numerical routine models the dynamic reaction mechanism, predicting the SPT penetration or blow count N. Based on typical resistance and rigidity values of cohesionless soils, an analytical solution is proposed to assess the effective friction angle. The results have proven it possible to model the penetration mechanism and, as a consequence, to use a dynamic test as an inverse boundary value problem to assess soil properties in granular materials.