Revealing aeroelastic effects on low-rise roof structures in turbulent winds via isogeometric fluid–structure interaction

Aeroelastic effects, which affect the dynamic responses of low-rise roof structures to extreme wind conditions, are often neglected or oversimplified in current wind engineering design standards and applications. However, it is crucial to understand the details of those aeroelastic effects for performance-based wind engineering. This paper presents an isogeometric fluid–structure interaction (FSI) tool to investigate the aeroelastic effects of wind pressure distributions on roof structures under different turbulent wind conditions. A representative low-rise roof structure is simulated with an FSI model using an Arbitrary Lagrange-Eulerian-based variational multi-scale formulation coupled with isogeometric Kirchhoff-Love shells. The simulation results are compared to the quasi-steady approach and wind load provisions from ASCE 7-22. It shows that the quasi-steady approach and the design standard underestimate the pressure fluctuations, indicating the necessity of using FSI simulations to capture the aeroelastic effect for the roof of low-rise structures. This paper also studies the impacts of different roof configurations, e.g., the number of roof panels and inflow turbulent intensity, on the distribution of pressure coefficients and roof deflections. For the given mean wind speed, the mean pressure coefficient remains almost the same regardless of the turbulent intensity and roof configuration. However, the pressure fluctuation (standard deviation) varies significantly with the turbulence intensity and roof configuration. The aeroelastic effect also leads to complicated roof deflections at the crucial location having the maximum pressure coefficient. The paper first describes the mathematical details of the FSI model and simulation setup. Then, the pressure coefficients by the FSI simulation and design code are compared. Finally, the roof deflection with different inlet turbulence intensities and roof configurations are presented and discussed.