Study on the Equivalent Impact Method of Long/Short Pulsewidth Loading Based on Cumulative Energy.

This study presents an equivalent test method of long/short pulsewidth impact based on energy accumulation during the elastoplastic response of the stepped beam. Through finite difference calculation, the stepped beam simplified from the sensitive unite of accelerometer used in this work is in the elastic response phase under the uniformly distributed impact load. Comparing the peak energy and the energy cumulative index based on the work of external force, it was found that the peak energy was not sensitive to the impact peak, while the energy cumulative index was affected by both the impact peak and the pulsewidth. Combined with the least action principle, the relationship between the impact peak and the pulsewidth was fit to ${T} = {C} \cdot {P}^{2}$ , and then the equivalent model of long/short pulsewidth impact was verified by Hopkinson bar and live firing tests with the error less than 10%. The selection of overload parameters in the dynamic impact test can get timely guidance, and the engineering process of the simulation equivalent test of extreme overload environment can be further promoted under the equivalent model.