Real-time monitoring of the full-scale flat-plate floor subjected to fire by acoustic emission and b-value analysis

This paper presents test results of mechanical behavior, failure pattern and b-value of full-scale flat-plate floor subjected to fire. The experimental results show that crack patterns on top surface of the flat-plate floor under fire are consistent with those at ambient temperature. The experimental results also show that concrete spalling has a significant impact on fire resistance of the flat-plate floor. Serious spalling would directly cause failure of concrete structures or members under fire even though they have not reached their fire resistance. On the basis of experimental results, acoustic emission parameters were analysed, which proved that b-value has a close relationship with the damage variation rate of the slab and can be used to estimate the damage process of the flat-plate floor under fire.