The effect of confinement and stand-off distance in blast tests

DANIEL AMBROSINI; BIBIANA LUCCIONI; GERALD NURICK; GENEVIEVE LANGDON; NEVILLE JACOB

Congreso; XVIII Congreso sobre Métodos Numéricos y sus Aplicaciones, ENIEF 2009; 2009

In recent years the explosive loads have received considerable attention due to differentevents, accidental or intentional, that have occured over important structures all over the world. Inconsequence, in the last decade there was an important activity in the research of explosive loads.Initially, this works were mostly empirical, but, in the last years, important researches have begun tobe developed.Much of this work has concentrated on the response of monolithic metal beams and plates toimpulsive loads. In particular, a set of experimental tests about clamped circular mild steel plates, ofradius 53 mm, subjected to blast loads travelling along tubular structures was carried out at the BlastImpact and Survivability Research Unit (BISRU, University of Cape Town). Some counter-intuitiveresults about incident impulse and plate response were observed in the experiments.The main objective of this paper is to study numerically the wave propagation in the tube used for thetests and to compare the response with that obtained experimentally. The effects of confinement,stand-off distance and charge mass on the reflected pressures and impulses are studied. The stand-offdistance is varied from 25 to 300 mm, and the load masses are varied from 4 to 15 g. Finally, the effectof the reflection on the plate is also analyzed. The analysis shows satisfactory correlation withexperimental results.