A novel Kolsky torsion bar technique is developed and successfully utilized to characterize the high strain rate shear response of a rate-independent end-linked polydimethylsiloxane (PDMS) gel rubber with a shear modulus of approx10 KPa. The results show that the specimen deforms uniformly under constant strain rate and the measured dynamic shear modulus well follows the trend determined by dynamic mechanical analysis (DMA) at lower strain rates. Contrastive Kolsky compression bar experiments are also performed on the same gel material with annular specimens. The dynamic moduli obtained from compression experiments, however, are an order of magnitude higher than those predicted by the torsional technique, due to the pressure caused by the radial inertia and end constraints.
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