Tension Hopkinson Bars
CAVS has two tension SHPB bars: aluminum and steel. These two bars use two different types of grips. The two types of specimens that can be tested have the following geometries:
The bar uses a hydraulic clamp to hold the incident wave from traveling down the incident bar. Pressure is built at the end of the incident bar in order to pull the specimen apart. The test is run by snapping a breaker pin in the clamping assembly. The resulting incident wave is then read via a strain gage on the incident bar. The wave propagates through the specimen and fails it. The resulting wave transmitted into the transmitter bar is read via another strain gage. The stress-strain curve is generated for the specimen by analyzing the incident wave, transmitted wave, and reflected waves.