On Mixed Isogeometric Analysis of Poroelasticity

Isogeometric finite element analysis of poroelasticity was first presented by Izral et al. 2013. The advantages gained, due to the smoothness the basis functions, over the standard finite element method were highlighted, all while using equal orders of interpolation for the displacements and pore pressure. In the finite element method, using different orders of interpolation helps in achieving stability but the use of lower order pressure interpolation leads to a lower solution accuracy. In this contribution, we present a mixed isogeomteric formulation for poroelasticity problems and explore the use of different orders of interpolation for the field variables, with a view to assessing the accuracy of the results for very small time steps. Numerical studies are performed on one and two-dimensional consolidation problems.