Postfire Damage Assessment of a Steel Industrial Building Exposed to Fire

Abstract

This study presents an experimental investigation on the structural effects of an ignited fire occurring in a steel warehouse building with storage racks located at a part of an industrial plant. In order to judge whether the structure needs to be dismantled, repaired, or reused after the fire, an on-site postfire damage reconnaissance study was conducted, and postfire mechanical properties, such as tensile tests and Charpy V-notch impact tests, and chemical analysis of the structural steels used for the building, were determined depending on specimens removed from the fire-damaged structural steel members. The bearing system of the one story industrial steel building having a span of 25 m consisted of 12 fixed supported rigid gabled moment frames with rafters and 12 m high columns of H Section (HEA) 360. At the roof, the bracings of circular hollow section (CHS) 114.3×3.0 and the purlins of C180 were used, while at the level of 8.9 m, crane beams were designed as HEA 600. From the tensile and impact tests, stress-strain curves, yield strength, ultimate tensile strength, elongation at fracture, and impact energy of the steel specimens were achieved. After all the results obtained from the tests performed at room temperature were evaluated, it was concluded that the structural steel elements affected but showing no distortions after the fire could be reused conveniently. In addition, the proposed approach to estimate the temperature exposed by the structural steels during the fire could have the potential to contribute to the existing relevant literature. In this study, it is experimentally explained what can be done about whether a steel structure needs to be dismantled, repaired, or reused after a fire event. First performing on-site damage detection and then taking samples from the structural load bearing system members’ chemical and mechanical tests should be carried out. Depending on the site investigation, it can be easily considered that the heavily deformed structural steel members become unusable and need to be renewed. From the tensile and impact tests of the structural steel elements affected but showing no distortions after the fire, their postfire mechanical properties are vital and should be ascertained. After all the test results were obtained, it can be concluded whether the structural steel members affected by fire can be reused, or need to be repaired or removed. In terms of ductility and elastic-perfectly plastic properties, it has been observed that after the fire the steel structural members showing no or even slight distortions can be reused conveniently. Thus, due to high cost of reconstruction of a steel building, a meaningful economy as well as acquisition in time can be achieved with this approach.