Understand and improve dynamic performance of transportation system — a case study of Luling Bridge

A transportation system includes transportation infrastructures and transportation vehicles. In most key transportation routes, bridges, especially long-span bridges, play an extremely important role in keeping the whole transportation line smooth and effective. Wind, as a common environmental phenomenon, exists in the nature almost all the time. In addition to the interaction between vehicles and supporting structures (e.g. roadways or bridges), the joining of the natural wind into the already coupled vehicle/supporting structure system makes the problem more complicated. The performance of the transportation system under complicated environmental conditions (e.g. wind) is critical to the hazard resistance capability of the whole transportation system, and thus should be well assessed. Long-span bridges, due to their flexible natures, are prone to exhibiting excessive vibrations caused by wind. So a suitable control scheme is sometimes necessary to improve the performance of the bridge under wind. An integral dynamic assessment and improvement scheme for the transportation system, including bridges, vehicles and roadways, is introduced for Luling Bridge in the South of the United States. With the fully coupled vehicle/bridge/wind model, the overall dynamic performance and accident risks of the vehicles can be assessed, followed by temporary control measures designed to improve the performance of Luling Bridge.