Experimental Investigation of Radial Inertia Effects in Hopkinson Bar Testing of Extra-soft Materials

摘要

We experimentally investigated radial inertia effects on dynamic response of a gel rubber in Hopkinson bar experiments. The redial inertia in such an extra-soft material resulted in a significant spike-like stress in the initial portion of stress-strain curve. Our experimental results indicate that this spike-like stress depends on both specimen geometry and differential of strain rate in the specimen. Using annual specimens and decreasing the differential of strain rate have been demonstrated to efficiently reduce the amplitude of the additional stress derived from the radial inertia in the specimen.