Holistic Robustness of Post-tensioned Floor Slabs under Fire Attack

Due to the advantages of readily achievable clear spans, small construction depth and minimum steel reinforcement, the use of post-tensioned floor slabs in the UK is becoming more popular. Although post-tensioned floor slabs have been used successfully in the United States, Australia and the Far East for a number of decades, without any evidence of problems under normal everyday conditions, their performance under fire, either through small-scale testing or experience from real fires, is unknown. Currently, designers adopt simple antiquated prescriptive rules that were developed for other forms of construction that bear no resemblance to the innovative mechanics of post-tensioned floor slabs. This research project will, for the first time, investigate the behaviour of post-tensioned floor slabs in fire, through experimental investigation coupled with theoretical modelling. The developed theoretical model will ultimately allow simple design rules to be developed which will ensure the safe and robust construction of buildings incorporating post-tensioned floor slabs.