The Damage Effects of Ultra-high Performance Fibre Reinforced Concrete Slabs under Close-range Blast Loading

In response to the needs for damage assessment and protection of high-value fortified targets, such as military command centers, against the close-range explosion threats, this paper investigates the damage effects of ultra-high performance fibre-reinforced concrete (UHPFRC) slabs with varying compressive strengths under close-range blast loading. Close-range explosion tests are conducted on eight groups of UHPFRC slab specimens to systematically analyze the influences of scaled distance and compressive strength on the dynamic response and damage evolution of the slabs. Experimental results demonstrate that the blast resistance of UHPFRC slabs is significantly enhanced by increasing their compressive strength at both scaled distances. A numerical simulation model for the damage effects of UHPFRC slabs under close-range blast loading is established based on the calibrated K&C model parameters and validated through experimental data. The coupled effects of key parameters, such as charge mass and compressive strength, on the damage effects of UHPFRC slabs are quantitatively studied by using the parametric analysis method. A predictive formula for the localized damage dimensions of UHPFRC slabs is developed through dimensionless processing, which comprehensively takes into account both charge mass and compressive strength.