A simplified non-linear poroelastic approach to transient effects induced by cylinder rotation in a porous medium
Gracieli Dienstmann1; Adrien Fayolle2; Felipe Schaedler de Almeida2; Fernando Schnaid2; Samir Maghous2
1 Department of Civil Engineering, Federal University of Santa Catarina, Florianópolis, Brazil; 2 Department of Civil Engineering, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
doi:10.20906/CPS/CILAMCE2017-0123
Resumo
Drainage conditions associated with loading rate effects during in situ vane-like tests are fundamental factors in the assessment and interpretation of shear strength properties of intermediate permeability soils. In that context, a simplified model for poromechanical analysis of consolidation induced by rotation of a rigid cylinder embedded within a porous medium is formulated. The approach is closely connected with the concept of deformation plasticity and relies upon the equivalence between the local behavior of a poroplastic material under monotonic loading process and that of an appropriate non-linear fictitious poroelastic behavior. The non-linear poroelastic model is conceived to capture the transient flow effects on the poromechanical response of the soil surrounding the rotating cylinder. Semi-analytical solutions are derived for pore-fluid pressure, displacement and stress distributions, allowing for the evaluation of rate effects in silty soils, with specific application to purely cohesive and frictional materials. The accuracy of the approach is assessed by comparison of model predictions with poroplastic finite element solutions. The results correlating the degree of drainage to normalized rotation velocity derived from proposed model may be a useful support for interpretation of in situ measured properties and foundation design purposes.
Palavras-chave: Non-linear poroelasticity; Porous medium; Transient flow; rotating cylinder; Finite element analysis