Temperature effects in concrete structures measured with fibre Bragg grating

Abstract

We analyse the action of fire, causing degradation in a concrete cantilever beam using dynamic testing. The structure is instrumented with two fibre Bragg gratings (FBG) sensors. One of them is used to measure vibration and another one is used to measure temperature inside of the cantilever beam, while the beam is exposed to fire. The temperature in the cantilever beam increased until 1 50 °C and a reduction in the strength of concrete can be observed through the modal analysis. A fibre Bragg grating interrogation system, based on tuneable filter method, is used for the static and dynamic measurements during the experiments. That system has low cost and it is easy to assemble and maintain when compared to other available instruments.

Temperature sensing in microwave heating of concrete using fibre Bragg grating sensors

“…The use of optical fibres as temperature sensors has been investigated by many researchers in different fields (Hirayama and Sano, 2000;Huang et al, 2003;Jung et al, 1998;Kersey and Berkoff, 1992;Kisaka et al, 2004;Lagakos et al, 1981;Pennisi et al, 2002;Protopopov et al, 2000;Ramesh and Wong, 1999;Seo and Kim, 1999;Silva et al, 2004;Wang et al, 2001;Lin et al, 2004;Zhan et al, 2004Zhan et al, , 2005. Several researchers developed optical-fibre-based temperature sensors by replacing a length of the optical fibre's cladding with a material that has a temperature-dependent refractive index (Pennisi et al, 2002).…”