Adaptive Crack Path Propagation Simulation with Experimental Validation for RC Shear Walls Based on Vector Form Intrinsic Finite Element

Conventional finite element methods suffer from critical drawbacks in simulating concrete crack propagation, including mandatory frequent remeshing, mesh distortion-induced numerical divergence and accuracy loss. Furthermore, robust crack evolution and autonomous crack path tracking remains challenging for existing algorithms. To overcome these limitations, this study develops a numerical model based on the Vector Form Intrinsic Finite Element (VFIFE) method for reinforced concrete (RC) shear walls. The proposed model adopts a discrete particle system, which eliminates the need for mesh rezoning and effectively avoids mesh distortion, and enables autonomous crack propagation direction selection via local stress-strain field judgment. The interaction between concrete and reinforcement across crack interfaces is represented using an equivalent interfacial spring formulation, which enables the evaluation of bond stress induced by crack opening. Comprehensive quasi-static tests were conducted on nine RC shear wall specimens with varying axial compression ratios, reinforcement ratios and aspect ratios for model validation. Numerical results show good agreement with experimental observations in crack patterns, propagation paths and damage distributions. Simulated horizontal crack heights have errors within 5%, and diagonal crack heights within 10%. The model also accurately captures crack opening widths and evolution of local bond stress induced by crack opening. Parametric studies show that higher axial compression and edge reinforcement ratios suppress crack growth, while larger aspect ratios promote cracking. Compared with conventional crack-tracking finite-element methods, the proposed VFIFE model maintains stable crack propagation through particle splitting and interfacial-spring mechanism without remeshing or global stiffness-matrix reconstruction, thereby reducing mesh-intervention cost and preserving crack-path accuracy. This VFIFE-based approach features high efficiency and stability, serving as a reliable tool for damage assessment and performance analysis of RC structures.