The overall objective of this collaborative research project is to develop a rational approach to bridge fire safety assessment by developing a fundamental understanding of the performance of steel girder bridge systems when exposed to fire. In recent years there has been a growing concern regarding fire hazard in bridges. Steel bridges are highly susceptible to fire induced damage and even collapse, since steel loses its strength and stiffness at high temperatures. The specific objectives are to (1) determine the parameters that affect the bridge vulnerability in a fire, (2) recommend means for mitigating the destructive effects of fire, (3) develop a qualitative strategy for classifying bridges based on fire risk, and (4) determine the post-fire residual strength. Experimental and numerical studies will be performed through collaboration between Princeton University and Michigan State University. This research will develop fundamental knowledge that is necessary to move forward with bridge fire safety provisions, and it will develop practical knowledge that practicing engineers need to make fast informed decisions after a bridge fire event. Guidelines will be developed for mitigating fire-induced collapse in steel bridge girders.
The guidelines developed are expected to lead to optimum and fire safe designs that are not only economical but are also based on rational design principles. Currently, bridge design regulations provide detailed specifications about how to design for loads such as earthquakes, but relatively much less information is available on how to design a bridge for a severe fire. This research will form the basis for developing design guidelines to provide improved fire safety and contribute to the development of US codes and standards dealing with the fire hazard in bridge girders. The PIs will disseminate this work to practicing engineers though publications and presentations at seminars and conferences. The project will also provide advanced training to graduate students on the topic of fire effects on structures through their involvement in the research activities of this project.
