EAPSI:Investigating Dynamic Loads and Response of Bridges and Moving Vehicles Subjected to Extreme Wind Gusts

Sauder Heather S, Ames IA

Investigators

Abstract

Flexible structures, such as long-span suspension bridges, can be susceptible to large amplitude vibrations and catastrophic failure above a specific wind speed. This project will investigate the experimental methods used to analyze structures in a wind tunnel in order to avoid disasters like the Tacoma Narrows Bridge collapse in 1940 and improve the design of vehicles to avoid overturning due to sudden crosswinds, like those from tornadoes or microbursts. This research will be conducted at the Bridge Engineering Laboratory at Kyoto University in Japan in collaboration with Dr. Hiromichi Shirato. Japan continues to push the limits of bridge engineering, the Akashi-Kaikyo Bridge in Kobe or the Namihaya Bridge in Osaka, and can experience several extreme wind events, typhoons, tornadoes and microbursts enhancing the applicability of these studies. The aeroelastic loads and response of structures due to gusty (time dependent) winds is not possible using the traditional frequency domain methods. Time-domain methods for both self-excited, motion-induced, and buffeting, turbulence-induced, loads have been recently developed using rational function approximations and buffeting indicial functions, respectively. These methods are also more applicable for finite element analysis and fatigue life estimations. The project will investigate the applications of rational function and buffeting indicial function technology as it relates to a bridge girder section and a moving vehicle subjected to a sudden crosswind. The results from the project will provide insights to improve the safety of the design of bridges and vehicles for gusty winds like tornadoes and microbursts. This NSF EAPSI award is funded in collaboration with the Japan Society for the Promotion of Science.