Modeling concrete cracking induced by non-uniform rebar corrosion using experiments and mesoscale peridynamics

With rapid advancements in civil engineering, reinforced concrete (RC) structures are extensively used in large infrastructure projects, such as sea-crossing bridges, port terminals, tunnels, and dams. However, exposure to seawater makes these structures highly susceptible to corrosion, accelerating deterioration and reducing their service life. This study investigates concrete cracking induced by non-uniform rebar corrosion through experimental tests and mesoscale peridynamic (PD) modeling. Two sets of accelerated corrosion tests were conducted, and a novel method for generating the heterogeneous mesoscale bond-based PD model was developed, utilizing meshless discretization directly. The model incorporates a time-dependent, non-uniform corrosion approach with a semi-elliptical distribution to represent the evolution and uneven expansion of corrosion products. The numerical method was validated against experimental data, showing strong agreement. The parametric study reveals that thicker concrete covers delay crack initiation, leads to longer and widely distributed cracks, and increase expansion pressure, while larger rebar diameters result in wider cracks and smaller expansion pressure. The shape of the aggregates has minimal impact on crack propagation. Additionally, the presence of multiple rebars accelerates the cracking process, potentially leading to concrete cover spalling. These findings enhance the understanding of corrosion-induced cracking in RC structures and offer valuable insights for improving structural durability and maintenance strategies.