Modelling and simulating the extreme wind effect on structures

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Over the past 20 years, more than 221 severe wind events were recorded yearly in Canada, and their effects on critical infrastructure have direct consequences on decreasing safety levels for populations in affected areas. Massive structures, such as long-span bridges, are considered more resilient to strong wind effects than high-rise buildings, towers, and electrical transmission lines; however the complexity of these structures implies higher vulnerability of their exposed structural elements such as bridge decks, towers and cables. The aerodynamic stability verification of each element of bridges, and of the entire bridge structure, became a standard criteria for the long-span bridges design process; however a global tendency of developing and implementing a new generation of twin and triple deck bridges, which have the outstanding advantage of extending the main spans dimensions to more than 2,000 m, is currently undertaken by several international research communities. The Canadian representation in this topic consists in the quadruple bridge deck prototype, proposed by the applicant, which was tested by conventional experimental methods, and proved to have better aerodynamic stability. However, for long-span bridges with complex deck configurations, to pass extreme winds safety criteria verification, novel and versatile tests and dynamic stability criteria must be diligently elaborated and carried out. The current research program aims at developing new experimental and analytical tools using the versatile Wind-induced Damage Simulator (WIDS) and by developing the integrated finite strip method (IFSM) for analyzing extreme aerodynamic responses of long-span bridges with complex (twin, triple and quadruple) deck configurations. The IFSM method represents a substitute for the well-known FE Method, which enables detailed modelling of material properties and complex geometries, and, more importantly, it allows for structure-wind interaction development. Because the application of the IFSM to aerodynamic responses of structures is a new research area, the analytical results will be validated using new techniques to simulate severe wind effects on scaled bridge elements such as bridge decks, cables, and towers. The WIDS Facility is able to reproduce the damage induced by extreme winds, and can recreate the ways in which structures experience effects of severe windstorms. The critical results obtained under extreme wind experimental conditions will serve as reference for developing the IFSM modules for the aerodynamic behaviour of the deck cables, and towers. At least six graduate students and three undergraduate students will be trained as part of the proposed research, enabling them to develop exceptional skills in designing and testing outstanding bridge structures.