Torsional Split Hopkinson Bar (TSHB) testing is an experimental technique in characterizing the behavior of materials at high rates of strain. A TSHB apparatus consists of three bars including a striker, incident and output bars. By applying a torque to the striker bar a torsional stress wave is generated that immediately begins to travel towards the specimen. Upon arrival at the specimen, the wave partially reflects back towards the impact end. The the wave partially transmits through the specimen and into the output bar. By measuring the elastic waves travelling through the two torsion bars using strain gages normally mounted in the middle sections of the bars, stress-strain curve of material can be captured. The location of strain gauges can affect the stress-strain curve. In this paper, the optimum locations of strain gauges are studied by experiment and numerical simulation. The numerical simulations are performed using Ls-Dyna commercial finite element code and the results are validated using the Lagrange diagram and experiment.
