A new pore collapse model, in which the effect of the binder in Plastic Bonded Explosives (PBX) is taken into account, is developed and integrated into the so-called hot-spot ignition model of shocked explosives. A two-dimensional hydrocode DYNA2D is used to simulate the shock initiation of PBX, with a reaction rate model consisting of a hot-spot ignition term, a slow-burning term at low pressure and a high-pressure reaction term. The numerical results show that the model can successfully describe the effects of the strength and the content of the binder, particle size and porosity of explosives on the shock initiation.

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A series of shock initiation experiments are performed on the PBXC03 explosives in different formulations to understand the influence of the explosive particle size on the shock initiation, and the in-situ pressure gauge data are obtained which show that shock sensitivity decreases with the explosive particle size under the test condition used in this paper. Moreover, a mesoscopic reaction rate model which is calibrated by the experimental data on a medium formulation PBXC03 explosive is adopted and then applied to predict numerically the shock initiation of other PBXC03 explosives in different formulations. The numerical results are in good agreement with the experimental data.

Foil-like manganin gauges with a variety of shapes used in different ranges of pressure for the one-dimensional strain mode and axisymmetric strain mode were designed for measuring the detonation pressures of explosives and high shock pressure in materials. In the stress range of 0–53.5 GPa, the pressure–piezoresistance relationships of the manganin gauges were calibrated by the light gas gun and the planar lens of explosive. The piezoresistance coefficients were obtained in different ranges of pressure. To verify the coefficients, the detonation pressure (CJ pressure) of TNT explosive was measured by the manganin gauges, which give similar CJ pressure values to those reported by Zhang et al (2009 Detonation Physics (Beijing: Ordnance Industry Press)) with the maximum relative deviation being less than 3%.

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