Modeling of reinforced concrete beams subjected to four-point bending using tensor damage phase-field model

Abstract

This study investigates the numerical modeling of failure mechanisms in reinforced concrete (RC) beams using the phase-field method, emphasizing its capability to simulate complex fracture behaviors under various loading conditions. The model incorporates a fourth-order degradation tensor to account for tensile, shear, and tensile-shear crack initiation and propagation. Six beam configurations from Marzec and Tejchman's experiments were modeled, varying dimensions, reinforcement ratios, and spans. The numerical results, obtained through finite element analyses, were compared with experimental data, revealing the model's accuracy in capturing crack patterns, failure mechanisms, and load-displacement responses. Key findings include the transition of failure modes from flexural to shear-dominated as beam slenderness decreases, consistent with experimental observations. Despite some discrepancies in peak load predictions, the phase- field model showed its potential for robust analysis of RC beam behavior, offering insights into fracture evolution and structural performance.