Aerodynamic instability performance of twin box girders for long-span bridges

Abstract

Twin box girders are a popular choice among long-span bridge engineers, and the aerodynamic performance of such a system is critical to the stability of a bridge under wind excitation. Two groups of twin-box girders with six representative slot width ratios varying from 0% to 100% were utilised to investigate the influence of different wind fairing shapes on aerodynamic instability performance for both torsional divergence and flutter of the girders. The girders with two wind fairing shapes for various slot ratios were investigated by wind tunnel tests and theoretical analyses. Based on the experimental results of static wind loads and critical flutter wind velocities, the symmetry of wind f..