Mechanical Characterization and Damage Modeling of Adobe Blocks Stabilized With Natural Plant Fibers

This study evaluates the mechanical performance of adobe blocks stabilized with natural plant fibers derived from Hyparrhenia hirta (HH) and Stipa offneri (SO). To this end, adobe specimens were fabricated by incorporating plant fibers into the soil matrix at contents ranging from 0% to 1% by weight of soil, with increments of 0.2%. After preparation and drying, three‐point bending and uniaxial compression tests were performed to characterize their mechanical behavior. A nonlinear constitutive model coupling elasticity and damage mechanics was developed to predict their mechanical response under loading. This model, based on the principles of continuum thermodynamics, provides a stress expression explicitly dependent on the damage variable. The experimental results show that fiber reinforcement improves flexural and compressive strength, stiffness, as well as the ductility of the composites. The numerical predictions accurately reproduce the experimental stress–strain curves, and statistical indicators confirm the relevance of the proposed model. These findings highlight the effectiveness of locally available plant fibers as sustainable reinforcement and provide a predictive framework for optimizing fiber‐reinforced earthen construction materials.