Probabilistic Evaluation Method of Wind Resistance of Membrane Roofs Based on Aerodynamic Stability

The membrane structure or membrane roofing system is lightweight and flexible, with wind being the primary cause of structural and membrane material failure. To evaluate the disaster prevention and mitigation capacity of the membrane roofing system and enhance the wind disaster risk management capabilities, this paper studies the exceedance probability evaluation method for different wind resistance requirements of membrane roofs. Taking Hangzhou in China as an example, the design wind speed risk curve fitted by polynomial is obtained by referring to the PEER performance-based seismic design method and considering the randomness of the wind field. A polynomial fitting method is employed to obtain the design wind speed hazard curve. Considering the nonlinear characteristics of the membrane roof structure, the relationship between the roof’s wind resistance requirements (vertical displacement limits) and wind speed spectrum values is approximated using a power function. An annual average exceedance probability expression is derived for different normal deformation demand values of the membrane roofs under wind load. Based on this, a wind resistance probability evaluation method for membrane roofs considering aerodynamic stability is proposed, along with specific steps and related analytical formulas. The results indicate that polynomial fitting provides an effective simplification for deriving the annual average exceedance probability expression for the wind resistance demand of membrane roofs. The performance-based wind resistance probability evaluation method allows for obtaining exceedance probability values for different displacement requirements with minimal structural analysis, which enriches the wind resistance design theory of membrane roofs and further ensures the structural safety of tension membrane roofs under wind load.