Investigation of concrete constitutive models for predicting the response, damage, and residual capacity of reinforced concrete beams subject to low velocity impact

Low velocity impact loading from accidental collisions is a common hazard for reinforced concrete components and structures used in infrastructure applications. Both the design of resilience measures and post-event forensic assessments of such structures can be supported using finite element analysis with advanced concrete constitutive models, however comparative benchmarking of available models to multiple experiments has been limited to date. This study comprehensively evaluates the performance of five concrete constitutive models – Continuous Surface Cap Model (CSCM), Karagozian and Case Concrete (KCC), Riedel–Hiermaier–Thoma (RHT), Concrete Damage Plasticity Model (CDPM), and Winfrith concrete – for analyzing the response of reinforced concrete beams to low-velocity impacts and the subsequent response of the damaged beam to static loading. The investigation includes simulation of five series of drop weight beam experiments conducted on reinforced concrete beams encompassing a range of reinforcement ratios, shear-to-flexural resistance ratios, and impact energies. The performance of each constitutive model is assessed based on comparisons with experimentally observed displacement time histories, damage patterns, and the load–displacement responses of the damaged beams under static loading. The results provide insight into the conditions under which each constitutive model replicates the experimental measurements with strong agreement when initialized with automatic parameter generation and default parameter assignments, while also identifying significant discrepancies in the nature and extent of damage predicted when using each model. This study highlights the importance of concrete constitutive model selection for accurate impact simulation and offers practical guidance for engineers and researchers in choosing appropriate constitutive models for assessing the response of reinforced concrete structures under impact loading.