Analysis of several strategies for the monitoring of bridges under fire

Bridge fires are a major concern because of the consequences that these kind of events have and because they are a real threat. This paper explains how temperature monitoring can be used to estimate the temperatures and mechanical response of a composite I-girder bridge affected by a fire. To reach this goal, the paper studies where high temperature sensors should be placed in a three spans bridge with a main span of 37,2 m which is affected by a tanker truck fire under its main span. The study combines the use of Computational Fluid Dynamics (CFD) to create the fire model, and finite element software to obtain the thermo-mechanical response of the bridge. Results show that accurate predictions can be obtained by locating the temperature sensors at the mid-height of the I-gider web with a maximum separation along the longitudinal axis of the bridge of 3 m.