Evaluating fire resistance level of reinforced concrete columns in basement during electric vehicle fires

This paper evaluates the Fire Resistance Level (FRL) requirements for Reinforced Concrete (RC) columns in basement carparks concerning Electric Vehicle (EV) fires. The rising prevalence of EVs raises important concerns about fire hazards, particularly due to the large lithium-ion batteries used in these vehicles, which can significantly extend fire duration and generate jet flames to spread fire between cars. This study aims to assess whether the prescribed FRL requirements for RC columns are sufficient to withstand EV fires within an enclosed basement carpark in Australia. The numerical analysis is conducted using Fire Dynamics Simulator (FDS) modelling and Finite Element Analysis (FEA). Results from the FDS modelling illustrate the temperature profiles generated during EV fires, suggesting these temperatures can surpass the standard fire curve. The subsequent FEA examines how these temperature profiles affect the load-carrying capacity of RC columns, providing insights into their fire resistance at elevated temperature. The FDS result indicates that the prolonged fire duration and the rapid-fire spread caused by jet flames contribute higher temperatures to EV fires than the Standard fire curve. The FE results indicate that the load capacity within an EV fire is less than the standard fire curve ISO 834, highlighting the necessity of EV fires in structural adequacy consideration, particularly fire load ratio selection.