Nonbuilding and Special Structures
Long-span dome structures are widely used for public assembly venues because of their large column-free space and efficient use of materials. When occupied by hundreds or even thousands of people, it would be devastating if they collapse or fail, which unfortunately happen frequently during extreme events, especially under tornadic winds. Although static effects of tornadoes on civil structures have been extensively studied, their dynamic impact has not been sufficiently investigated. In this study, non-stationary characteristics of tornadoes and their dynamic impact on a long-span dome structure is systematically investigated. In particular, the time-variant wind pressure on the dome surface induced by a translating tornado is characterized through Computational Fluid Dynamics simulations; and the obtained wind pressure is then mapped onto the finite element model of the dome structure, and a transient time-history analysis is conducted to characterize the tornado-induced dynamic responses. It is observed that non-stationary wind pressure and the induced dynamic structural responses are significant, when the core radius of the tornado approaches the dome edge. More severe dynamic impact is observed when the tornado first approaches the dome structure, i.e., when the core radius of the tornado passes the dome structure for the first time. This research will facilitate in better determining the design tornadic wind load, helping to achieve tornado-resistant design.