Estimation of multiple limit state responses with various mean recurrence intervals considering directionality effects

Assessment of system reliability of structures against wind loading requires evaluation of the joint probability distribution of multiple limit state responses with consideration of wind and aerodynamic directionality effects. While the directionality effect has been extensively addressed in literature on the estimation of probabilistic single limit state response, it is not the case for multiple limit state responses. This study revisits estimation of extreme responses with various mean recurrence intervals, with a focus on adequate definition of directionality factor. A new framework is then presented for estimation of joint probability distribution of multiple extreme responses with consideration of directionality effect. This new framework can be considered as an extension of existing efforts on directionality effect for single limit state response to multiple ones, thus help in better assessing system reliability of structures against wind loading. The proposed framework is applied to responses of claddings on a large-span saddle type roof.