A Framework to Extend Performance-Based Engineering for the Examination of Wind Loads from Thunderstorm Downbursts and Tornadoes

Research Category: Engineering and Technology
Presenter: Viet Le

Performance-based engineering (PBE) in the civil engineering field is a developing methodology that rigorously assesses the probabilistic risk that a structure faces when exposed to a man-made or natural hazard. Research has been conducted to extend this practice to wind engineering, with preliminary applications focusing on wind loads from large, synoptic phenomena such as hurricanes and extratropical cyclones. For these systems, traditional wind engineering approaches such as frequency domain analysis (i.e., “Davenport chain”) can be utilized. On the other hand, meso-scale meteorological systems such as thunderstorm downbursts and tornadoes with their complex, evolving properties render these analytical methods inadequate because of their inability to predict non-stationary wind load and structural response. As a result, the development of PBE for the evaluation of these windstorms on civil infrastructure is currently lacking. To address this issue, this research proposes a framework by which damages of vertical structures subjected to loads from thunderstorm downbursts and tornadoes are characterized from a performance-based perspective. Structural damages are computed with physically informed wind fields, using information from full-scale data (if applicable), and efficient structural models. Numerical simulations are complemented with wind tunnel experimentation using an innovative flow-altering device. Key components of PBE including fragility analysis, hazard analysis from publicly available data sources, and loss assessment of relative life-cycle repair (intervention) costs are demonstrated. Successful application of this approach can ultimately provide information regarding the structural performance of the built environment to promote sustainability under wind loading conditions from thunderstorm downbursts and tornadoes.