Study On Reynolds Number Effects Of Typical Long-span Bridge Section

As the rapid development of the society, long-span bridges have been springing up worldwide since 20 th. As an important factor in long-span bridg design and construction, accurate wind load calculating has great influence on structural safety and cost control. Reynolds number effect is an unsettled problem in ati--wind design and study of bridges, and it’s more outstanding with common bridge sections sreamlined. Besides, as an important factor in tunnel tests of Reynolds number effect study, length-width ratio is with little consideration in privious studies. Based on Reynolds number effect of a typical flat-box girder bridge deck and the possible influence of length-width ratio on it, this paper mainly focuses on following research:Firstly, Reynolds number effect on the aerodynamic force coefficients, surface pressure distribution and correlation were further studied based on the pressure measurement in low Reynolds number conditon. The results show that the drag coefficient is influenced more than other coefficients, and the minimum value area of mean wind pressure coefficient is very important for Reynolds number effects research. Besides, the bottom and downsream inclined web are more influenced in Reynolds number effecting on circumferential correlation of aerodynamic force coefficients.Secondly, analyzing the effects of three length-width ratios on the change law of aerodynamic force coefficients surface pressure distribution and correlation, it’s revealed that the increasing of length-width ratio will activate Reynolds number effecting on the drag coefficient and lift coefficient, and the minimum value area is more influenced by length-width ratio in Reynolds number effecting on mean wind pressure coefficient. Besides, the upper surface of bridge section is mainly influenced by length-width ratio in Reynolds number effecting on circumferential correlation of aerodynamic force coefficients.