Abstract:The governing partial differential equations describing one-dimensional stress wave propagations within a viscoelastic specimen in a Split Hopkinson Pressure Bar (SHPB) test are established. Coupled boundary conditions at both ends of the specimen are derived by using the characteristic equations in the incident bar and the transmitting bar. Laplace transform of the governing equations turns the group of PDEs into an ordinary differential equation, which is solved analytically with the transformed BCs. The inverse Laplace transform of the solution gives the time histories of stress at arbitrary site. A modified Fixed Talbot (FT) algorithm is proposed to do the inverse transform numerically. Results calculated by using this algorithm agree very well with the results obtained by finite difference simulation of the same problem. This proves the efficiency and accuracy of the developed technique. Using this technique, parametric investigations are conducted to study the influences on the transmitting stress waves of specimen length and material parameters.