Multi-Scale Simulation of Fracture and Damage of Concrete

Current research on concrete materials and structures is largely experimental, relying on specimen casting and mechanical testing to validate material designs. This approach leads to long research cycles, high costs, and inherent variability, often requiring empirical adjustments for structural safety assessments. Such reliance on experimentation is increasingly inadequate to meet the evolving demands of modern cementitious composites. With advancements in mechanical theory, computational methods, and digital technologies, numerical simulations of concrete damage and fracture have become essential for shifting from traditional design to multi-scale, simulation-based optimization. These methods generate large datasets that validate existing theories and provide insights into multi-scale physical quantities, critical for correlating micro-/meso-scale and macro-scale behavior. This chapter explores multi-scale simulations of concrete damage and fracture, focusing on modeling techniques such as random models, CT image-based high-fidelity models, and hybrid models. It also introduces the basic theory and numerical implementation of the continuum damaged plasticity model, discrete cohesive crack model, and phase-field model, highlighting strategies to upscale micro-/meso-scale heterogeneity for structural damage and fracture assessment. The methodologies and findings offer valuable insights for developing new cementitious materials and structures.