Fatigue damage of shipborne solid rocket motor propellant under swing loading

A fatigue damage evaluation method of propellant under swing loading was established for some solid rocket motor(SRM).Firstly,the fatigue damage property of composite solid propellant was acquired by fixed stress amplitude cycle loading experiment.Secondly,the stress spectrums of SRM nodes with time were obtained by method of finite element analysis.Finally,the rain-flowing counting method and the Miner's linear cumulative damage theory were applied to evaluate the fatigue damage of SRM.The results show that the fatigue damage of motor's dangerous area reaches 0.085 5 by ship motion loading across a year.