Fire induced concrete spalling in combination with size effects

Abstract The size effect has its origin in fracture mechanics and describes the formation as well propagation of cracks brittle solid materials dependence specimen size. However, concrete spalling damage behaviour on a macroscopic scale for different sized specimens case fire. Concrete is very complex yet not fully understood phenomenon. To reduce effort fire tests to analyse mixtures, this study investigates susceptibility six mixtures three sizes. sizes were divided full slabs (1.8 m × 1.2 0.3 m), intermediate cuboids (0.6 0.6 m) small cylinders (Ø0.15 m). For purpose, novel test set-up was built or twelve simultaneously ensure similar heating regime every specimen. All exposed one side remained unrestrained. A occurred four mixtures. Compared reduced significantly all smaller Additionally, did occur specimens. results show that an essential parameter investigate mixture. future investigations testing conditions must be adjusted recreate slabs.