continuous points as well as discontinuous points, such as a crack. The ability to apply this equation to all points renders peridynamics more useful for fracture analysis than the conventional continuum mechanics, which requires knowledge of fracture mechanics. For example, there is no need for a separate crack growth law based on stress intensity factors in peridynamic analysis. In this study, a peridynamic numerical scheme based on Eq. 24.2 is formulated and applied to split Hopkinson’s pressure bar (SHPB). Figure 24.1 shows a schematic diagram of an SHPB. It includes a striker bar, an incident bar, a specimen and a transmission bar. All the bars are made of 347 stainless steel with a Young’s modulus E ¼193 GPa and a mass density ρ ¼8,027 kg=m3. The incident bar and the transmission bar are instrumented with strain gages. In the SHPB test, the striker bar is fired into the left end of the incident bar. This creates a constant pressure input with a period of time. The striker bar is 0.191 m in length. The wave velocity in the striker can be calculated as c ¼ ffiffiffiE ρ s ¼4903 m=s (24.3) The duration of the constant pressure input is equal to the time the wave takes to travel through the striker twice, i.e. t0 ¼2 0:191 4903 ¼ 7:79 10 5s (24.4) It is also equal to the time when the striker bar separates from the incident bar. Figure 24.2 shows the incidence bar and the strain wave generated based on a pressure of 10 MPa in firing the striker bar. For comparison purpose, experimental results are scaled to numerical result. Fig. 24.1 Experimental and peridynamic result of SHPB simulation 196 T. Jia and D. Liu
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