Dynamic shear response of a polymer bonded explosive using a modified Hopkinson bar apparatus

Abstract

An innovative Hopkinson pressure bar system for testing the shear response of materials at high strain rates has been developed. A novel single-lap specimen of a polymer bonded explosive (PBX) is used. Instead of strain gauges mounted on the bars, one quartz force transducer is sandwiched between the clamp and the transmission bar to directly measure the weakly loading forces. A laser gap gauge is employed to monitor the shear strain of the specimen, which is based on the luminous flux method. Finite element code ANSYS is used to analyze the stress state in the specimen. Experimental results show that this new method is effective and reliable for determining the shear stress-strain responses of the soft materials at high strain rates.