Probabilistic dynamic responses of RC columns under vehicle collision considering three-dimensional random fields of concrete properties

In recent years, the frequency of vehicle–pier collisions has increased considerably, endangering both public safety and structural integrity. However, many existing studies have failed to account for the inherent three-dimensional (3D) spatial variability of concrete material properties in reinforced concrete (RC) structures. In this study, the dynamic behavior of RC columns under vehicle impact is investigated using a stochastic finite element framework that explicitly incorporates 3D random fields of concrete properties. Random fields of concrete compressive strength are characterized by the stochastic harmonic function representation method. Based on these random fields, the stochastic dynamic responses of RC columns are analyzed using the probability density evolution method (PDEM). Comparative investigations between deterministic and stochastic models are carried out to reveal the influence of material uncertainties on the dynamic responses and failure mechanisms of RC columns under impact loading. Furthermore, the effects of correlation lengths and 3D spatial variability on the dispersion and probabilistic distribution of structural responses are examined to elucidate the role of spatial variability in impact resistance. The results provide new insights into the probabilistic characterization and reliability evaluation of RC structures and contribute to the development of more reliable and resilient designs against accidental vehicle collisions.