Numerical modeling of the mechanical behavior of a one-story adobe house using DIANA FEM

Abstract

This research develops a nonlinear numerical model of the structural behavior of a one-story adobe house using the finite element method in DIANA FEM. The study is based on representative mechanical properties of traditional adobe reported in the scientific literature, considering compressive strength between 0.8–2.5 MPa, tensile strength between 0.08–0.20 MPa, and a modulus of elasticity in the range of 250–450 MPa. The Total Strain Crack Model, suitable for quasi-brittle materials, was implemented, incorporating principal tension cracking criteria (Rankine), a softening law regularized by fracture energy, and shear retention to capture the progressive stiffness degradation. The analysis was performed using an incremental nonlinear static pushover procedure, applying an initial gravitational load followed by controlled lateral displacement. The results showed that cracking begins at an approximate drift of 0.20%, with stiffness loss exceeding 40% after the elastic-inelastic transition. Maximum lateral capacity was reached at drifts between 0.8% and 1.2%, confirming limited overall ductility (μ < 2.0). The structural response was dominated by tensile strength and fracture energy, while compressive strength had a secondary influence on peak capacity. Parametric analysis demonstrated high structural sensitivity to variations in tensile strength; increases of 15% in this parameter resulted in increases of approximately 20–25% in maximum lateral capacity. The numerical damage pattern showed dominant diagonal cracking in load-bearing walls and stress concentrations at the corners of openings, consistent with previous experimental data. It is concluded that nonlinear modeling in DIANA FEM allows for the consistent reproduction of the characteristic failure mechanisms of adobe.