A study on spatial correlation of natural wind

In the design of aeroelastic structures, the effect of gust response is taken into account. When the structure is long and has low natural frequency, the spatial correlation of the wind in the low-frequency range affects the gust response. However, data from field measurement about spatial correlation of natural wind are generally not available. Therefore, data concerning the spatial correlation of the natural wind were measured on two Honshu-Shikoku Bridges. The results show that the spatial correlation of the natural wind is lower than that specified in the wind-resistant design manual in the low-frequency range. In order to evaluate the effect of the difference of the spatial correlation of the wind on gust responses, a gust response analysis was conducted. The results show that gust responses calculated using measured spatial correlation is much smaller than the ones calculated using spatial correlation specified in design manual. This means that there is a possibility to be able to ease the design specifications of long span bridge concerning gust response.