Evaluation of mast measurements and wind tunnel terrain models to describe spatially variable wind field characteristics for long-span bridge design

Abstract

The quality of the information about the wind field characteristics is crucial for accurately predicting the structural response of a long-span bridge subjected to dynamic wind loads. In this paper, in situ mast measurements and terrain model wind tunnel tests are compared with full-scale measurements of the wind field along the Hardanger Bridge girder. The aim is to investigate the performance of mast measurements and wind tunnel terrain model tests in predicting the wind field characteristics for long-span bridges in complex terrains. Wind field spatial variations and statistical distributions for the mean wind velocity and turbulence intensity are investigated. Extreme value statistics have been applied to compare the mean wind velocity recordings from two different measurement periods. Results showing terrain-induced effects on the wind directions, turbulence intensities and mean wind velocities are presented. Simultaneous spanwise wind profiles for the mean wind velocity and along-wind turbulence intensity are compared between the terrain model wind tunnel tests and the full-scale measurements, and large nonuniformities are identified. The extreme profiles of the turbulence intensities vary as much as 100% along the span, and the mean wind velocity profiles vary up to 50% along the span.