Enclosed blast response of fibre-reinforced composite plates — with and without pre-damage

Composite structures have been increasingly used in military applications for their high specific strength and stiffness, combined with low thermal and electromagnetic signature properties. In such applications, resistance to blast is an important criterion, yet studies comparing different choices of material in the same experimental set-up are scarce. This comparative experimental and numerical study investigates the enclosed blast response of quasi-isotropic carbon and glass fibre composite plates. The study was performed on both undamaged and pre-damaged plates to examine the notch-sensitivity of the composite plates under blast loading. Pre-damages were done with two symmetrically located holes, drilled or shot with fragment simulating projectiles. Results were benchmarked against prior findings for thin steel plates under identical loading conditions. Experimentally, the carbon fibre composite plates exhibited the highest blast resistance (measured by mass of the explosive charge at failure), followed by equal-mass steel plates, and equal-mass glass fibre composite plates. Notably, pre-damage caused a more pronounced reduction in blast resistance for steel plates than for carbon and glass fibre composite plates. Interestingly, pre-shot and pre-drilled composite plates displayed comparable blast performance, suggesting insignificant notch-type dependence. Finally, experimental data was used to validate a numerical model, which achieved good correlation with test results. • Carbon fibre and glass fibre composite plates are compared under enclosed near-field blast. • The carbon fibre composite plates showed the highest blast resistance at equal surface weight. • Pre-damages in the form of drilled or shot holes were introduced in some of the plates. • Drilled and shot plates showed similar blast resistance.