Impact resistance of steel fibre reinforced ferrocement channels: experimental and numerical study

Evaluating the impact resistance of ferrocement channels is essential for their application in low-cost roofing and similar structural components. This study investigates the impact response and crack propagation behaviour of unreinforced and steel fibre-reinforced ferrocement channels subjected to repeated drop-weight impact loading. Impact performance was assessed in terms of energy at first cracking and failure, post-crack resistance, ductility, and crack width evolution. Experimental results demonstrated that steel fibre reinforcement significantly enhanced impact toughness, with approximately 2.4-fold increase at first crack and nearly 4-fold increase at failure, and increased the impact ductility index by about 70%, indicating a clear transition from brittle to ductile behaviour. Fibre inclusion also reduced crack width by up to 68% and maintained narrow crack openings under repeated impacts. A numerical parametric study showed that steel fibres enhanced impact energy absorption by 7.6-14.9% depending on the number of welded mesh layers, while increasing mesh layers beyond two offered marginal benefits. Randomly oriented fibres exhibited higher impact toughness than planar orientation, with improvements of up to 37%. Overall, two layers of welded mesh were found to provide optimal impact resistance, irrespective of fibre presence.