Fiber Optic Sensors for High Temperature Monitoring

P. Rinaudo, B. Torres Górriz, D. Barrera Villar, S. Sales Maicas, P.A. Calderón García and I. Javier Payá-Zaforteza.
Universitat Politècnica de València (Spain), ES

Keywords: fire, high temperature, structural health monitoring (SHM), fiber optic sensor, fiber bragg gratting


Recent events such as the fires on the Channel tunnel (1996), St. Gotthard (2001), the Twin Towers in New York (2001), The Windsor Building in Madrid (2005) and the collapse of the MacArthur Maze in Oakland (2007) show the importance and the necessity of a monitoring strategy for fire vulnerable structures. Through this strategy, the assessment of fire damaged structures would be possible and if necessary, the demolition operation would be guided. In order to monitor structures subjected to fire it is essential to have high temperature sensors. thermocouples have the typical inconvenience of the electric sensors. For instance, they cannot be placed on electric lines due to their electromagnetic interference, they cannot be multiplexed and they have uncertainty under humid environments. Fiber optic sensors are proposed due to their advantages compared to electric sensors. In this article the steps in the development of this high temperature sensor are presented. In the first part of the article the operating principle of the fiber optic sensor to measure temperature is exposed. Then, the experimental tests completed to prove the accurate performance of the sensor are explained and their main results are shown.