A novel method in dynamic shear testing of bulk materials using the traditional SHPB technique

This paper aims to propose a novel experimental method to study dynamic shear properties and constitutive behaviors of bulk materials using the traditional split Hopkinson pressure bar (SHPB) technique. In this method, a new kind of double-shear specimen (DSS) and fixture is specially designed for the SHPB system. With this setup configuration, the plastic properties of materials can be obtained conveniently at high strain rates under the state of simple shear. The deformation and failure process of the shear zone can be observed directly by using a high-speed photography. Another advantage of this method is that reloading on the specimen can be prevented for the purpose of post-test observation, with the application of the stress reversal Hopkinson technique (Nemat-Nasser et al., 1991). Using this method, the 603 steel was tested at strain rates from 2500 s(-1) to 48000 s(-1). With the aid of finite element analysis (FEA), it's found that the shear stress and shear strain play dominant roles in the stress/strain fields. The distribution of the maximum shear strains in the shear zone showed good consistency with the fracture patterns of the tested samples. Through comparison between the tested and simulated shear stress-shear strain curves, very good agreement is noted for all the tested cases. (C) 2016 Elsevier Ltd. All rights reserved.