Extended isogeometric analysis of a progressively fracturing fluid‐saturated porous medium

An extended isogeometric analysis (XIGA) approach is proposed for modeling fracturing in a fluid-saturated porous material. XIGA provides definition of the discontinuity independent underlying mesh layout, which obviates need knowing crack extension direction priori. Unlike Lagrange shape functions used standard finite element approach, non-uniform rational B-splines (NURBS) provide higher-order interelement continuity leads to continuous fluid flow also at boundaries, thereby satisfying local mass balance. It an improved estimate path due smoother stress distribution. The NURBS basis are cast data structure using Bézier extraction. To model discontinuity, Heaviside sign function utilized within displacement and pressure fields, complemented by shifting blending techniques enforce compatibility perpendicular parallel path, respectively. Different aspects assessed through examples comprising straight curved paths stationary propagating discontinuities.