Experimental investigation of an aggregate material behavior under confinement at high strain rate

Low velocity impacts can ignite explosives or energetic materials. Ignition depends on the mechanical behavior of the energetic material which needs to be characterized for both high pressure level and high strain rate. A technique based on the Split Hopkinson Pressure Bars system is proposed to reproduce these loading conditions. A cylindrical specimen is placed in a confining ring and is dynamically compressed. The ring prevents the radial extension and confines the specimen. Each ring is designed to plastify and to obtain a constant radial pressure during the test. Some experiments are carried out on an inert aggregate material and show the validity of this experimental device.