Fracture‐mechanical numerical simulation of punching in reinforced concrete foundations considering soil‐structure interaction and design code evaluation

Current design provisions for punching shear in foundations, including Eurocode 2 (2023) and fib Model Code 2020, are mechanically based models partly calibrated against experimental data from isolated flat slabs and foundation specimens. The available experimental database for foundations is small and only partly representative of realistic dimensions and soil‐structure interaction. Thick footings and raft foundations develop very high punching capacities that often exceed laboratory load limits, and many studies rely on scaled specimens or simplified soil representations. To address these limitations, validated nonlinear fracture‐mechanical finite element simulations are performed, accounting for soil‐structure interaction. A systematic parametric study comprising 190 simulations investigates the influence of shear slenderness, slab thickness, concrete strength, reinforcement ratio and soil stiffness on punching resistance. The results show that these parameters interact strongly and are not consistently represented in current design provisions. Comparison with EC2:2023 and MC2020 indicates overall good agreement, but also significant parameter‐dependent deviations.