Grant: Collaborative Research and Development Grants

Every year severe wind storms cause significant damage to Canadian residential structures and infrastructure. Much of this damage goes undocumented, particularly from an engineering viewpoint, even though such information is important. Detailed knowledge of wind damage is important to determine the performance of building and design codes, to develop of insurance risk or loss models, to improve the ability of meteorologists to forecast extreme events (such as tornadoes and downbursts) and to issue appropriate warnings, and to validate laboratory test results. However, to achieve these goals quantitatively, it is imperative that reasonably accurate estimates of the peak wind speeds are available. This is seldom the case. Thus, the damage observations must be used directly to infer the wind speed. The current proposal addresses this issue, focussing on two particular aspects of storm damage, namely, windthrow (or uprooting) of trees, and damage caused by, and the flight distances of, windborne debris, and how these can be used to estimate peak wind speeds. To achieve these goals, damage surveys will be conducted with Storm Damage Survey teams from Environment Canada and detailed analysis and experiments will be conducted in the laboratory with full- and reduced-scale models. The expected outcomes of the project include an assessment of common failures that are not adequately addressed in the current Canadian building code, the damage costs associated with these failures in the context of insurance risk modelling, and the development of a set of calibrated damage scales that will allow Environment Canada meteorologists to provide improved assessments of the wind speeds in severe storms. The research will involve five principal investigators at two universities as well as providing training for three graduate students and one undergraduate student over a period of three years.