An Interface-enriched Generalized Finite Element Method (IGFEM) is proposed for the coupled hydro-mechanical analysis of deformable, saturated porous media consisting of distinct, perfectly bonded material phases. The spatial discretization of the momentum balance equation and storage equation is derived using IGFEM, followed by the time discretization of these equations via the generalized Newmark method. This leads to a fully coupled system of nonlinear equations, which is solved iteratively using a monolithic update scheme. The IGFEM formulation is proficient in accurately capturing weak discontinuities in both the solid phase displacement field and the fluid phase pressure field at material interfaces, by placing enriched nodes directly on these interfaces. Several numerical examples demonstrate that the proposed IGFEM formulation not only matches the accuracy of standard FEM with a conformal mesh, but also outperforms the eXtended/Generalized Finite Element Method (XFEM/GFEM). Moreover, it can accurately capture complex, non-planar interfaces without requiring mesh alignment, highlighting the method's flexibility and robustness for practical hydro-mechanical analyses of porous media with geometrically intricate boundaries. Overall, IGFEM provides a highly accurate and efficient approach for solving transient coupled problems involving material interfaces.

Previous research has shown that the material properties of a three-dimensional printed strain hardening cementitious composite (3DP-SHCC) can significantly vary, depending on the printing system with which it is produced. However, limited research has been performed on the reproducibility of hardened mechanical properties under identical printing conditions. In this study, the consistency of hardened properties, including compressive strength, flexural strength and deflection, and tensile strength and strain, was tested from materials printed during three separate but identical printing sessions. The research shows that with 3DP-SHCC, significant variations in mechanical properties between printing sessions can be expected.