Spalling sensitivity test on concrete

Concrete sensitivity to spalling in fire is still a critical issue, as no reliable predictive model is currently available. Hence, so far, experimental testing is the most effective means of investigation. This is the reason why an experimental setup has been designed (and discussed in the Rilem TC 256 SPF) by the authors, based on 800x800 mm concrete slabs installed in a steel frame, aimed at applying a biaxial membrane compression. Load and slab thickness can be adjusted in order to simulate the actual service conditions of concrete elements such as tunnel lining segments. The loading system is placed on a horizontal furnace pow-ered by a propane burner fitted with an automatic control system, allowing to follow the prescribed heating curve. This setup allows comparing different concrete mixes as regards their sensitivity to spalling in realistic service conditions and can be of considerable help in initial material testing for strategic infrastructures such as tunnels.