Evaluation of steel structures integrity in a post-fire condition: Case study of the serradells sports centre in Andorra

A new methodology is proposed for assessing the integrity of steel structures in a post-fire condition. The work includes a combination of numerical simulations and experimental techniques. A fire that affected the sports centre Els Serradells in Andorra in 2018 is presented as a case study. Flame propagation was characterized using computational fluid dynamics and combustion simulations; the obtained results were compared with the data collected on site, and time-temperature laws that affected the structural elements were determined. These laws enable the numerical characterisation of the heat transfer and temperature in structural members; several tests were conducted afterwards. The numerical results matched the chemical and microstructural alterations observed in steel, which allowed rationalizing reconstruction costs because the intervention was limited to elements with residual deformations. This methodology is expected to help increase the number of buildings that will be refurbished after a fire instead of being demolished and rebuilt.