The use of the split Hopkinson pressure bar (SHPB) techniques for materials testing under a high rate of loading is described, including various modifications of the original compression testing set-up for tension testing, torsion testing and dynamic fracture testing. Details of measurement techniques and instrumentation are included together with the calibration of the air gun and strain wave measuring system. The SHPB techniques provide a relatively cheap and simple method for high strain rate materials testing with an acceptable level of accuracy when sufficient care is taken for the proper lubrication of the interfaces and the correct length—radius ratio of the specimen is chosen. The limitations of the method are discussed and possible improvements using FFT (fast Fourier transform) techniques to take into account dispersion effects are considered.

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The influence of dynamics on a propagating fatigue crack has not been studied experimentally yet mainly due to quasi-static loading from traditional fatigue-testing machines. To overcome this serious drawback, a novel base-excited fatigue-testing device was designed and built to allow measurement of the dynamic responses of a single-edge-notch beam (SENB) under a growing fatigue crack. In this paper, the details of the novel test rig including initial development, modification and instrumentation are given. The experimental time histories obtained for harmonic and chaotic excitations have shown that the fatigue rig is capable of generating a wide range of loading patterns. Moreover, the experimental crack growth curves and features of the fracture surface have confirmed that the rig is capable of inducing proper fatigue cracks.