Explosion tests on blast doors
In a recent field test, 100kg of bare high explosives (TNT equivalent) was detonated in free air to investigate the performance and behaviour of five sandwich blast doors. The bare charge pack, placed 1.5m above ground level, consists of 365 sticks of PE4 explosive (NEQ factor = 1.19). A single stick of COMP4 booster explosive with a length of detonator chord was placed at the centre of the pack; its purpose was to ensure complete initiation of the PE4 explosive. Blast doors were fabricated as sandwich panels with attendant locking mechanism and shear pins to resist the blast overpressure. Idealised pressure-time histories were used to design the blast doors. Each blast door, located equidistant from one another and arranged in a circle with the explosive charge at the centre, was subjected to different load intensities by positioning them at prescribed range from the explosive source. Details of the blast doors, experimental set-up, blast overpressure data and limited acceleration record are presented. Calculated peak overpressure values, though underestimated, were in agreement with measured data. All the blast doors survived the test, except for one door positioned closest to the explosive source; the excessive blast overpressure at this close range resulted in localised damage to the panel/locking mechanism area. However, the structural system of this door remained undamaged.
T. S. Lok, BSc(Hons), PhD, CEng, MIStructE, Eur-Ing, PEng, MASCE, MIES
Associate Professor, Nanyang Technological University, School of Civil and Environmental Engineering, Nanyang Avenue, Singapore 639798
Author(s): Lok, T S
Keywords: explosion loads;full scale tests;blast doors;sandwich panels;overpressure