Lateral impact response of circular RC columns at low temperatures: Experimental and numerical modelling

Reinforced concrete (RC) infrastructure in polar and cold regions is exposed to the extreme low temperatures and subjected to accidental impact loadings. This study experimentally and numerically investigates the lateral impact behavior of circular RC columns over a temperature range from −80 °C to ambient temperature (20 °C). Two axial compression tests were firstly conducted to obtain the baseline load-carrying capacities, while five drop-hammer impact tests were then performed to explore the dynamic responses and damage evolution. The test results showed that the decrease in temperature significantly enhanced the axial compression capacity. As the temperature decreased from 20 °C to −80 °C, the average impact force increased by 9.6%, while the ultimate and residual displacements decreased by 27.9% and 48.1%, respectively. Moreover, finite elements were developed to reproduce the impact responses and damage evolution, demonstrating good agreement with the experimental observations. Parametric analyses further revealed that increasing impact mass and velocity markedly amplified structural deformation and damage, while increasing reinforcement ratios effectively suppressed both deformation and residual damage. These findings provide new insights into the low-temperature dynamic impact performance of RC structures and establish a robust analytical basis for the optimized design and assessment of infrastructure in cold regions.