A Comparison of ASCE/SEI 7–22 Tornado-Induced Load Provisions for Residential Low-Rise Buildings to Those Evaluated Using Physical Simulation

In this study, the loads induced by tornado-like vortices on scaled models of eight low-rise residential buildings with real-world shapes in a typical North American community are quantified and compared to the provisions provided by ASCE/SEI 7–22. Physical simulations of the interaction between translating tornado-like vortices representative of EF1-, EF2- and EF3-rated tornadoes and the scaled models were performed in the WindEEE Dome at the University of Western Ontario. Three internal pressure scenarios were numerically simulated. The tornado velocity gust factor was identified as a critical parameter when translating loads from the model to full-scale. The uplift forces on the whole roof in the internal pressure scenarios with one dominant opening are between 44% and 63% higher than the distributed leakage scenario, highlighting the importance of keeping the integrity of the envelope. Revised values of the internal pressure coefficients and external pressure coefficients or correction factors may be used to improve the ability of the standard to provide safer design loads.