Critical shock response spectrum of a beam under shock loading

The offshore structures experience severe shock environment caused by storms, episodic waves, icebergs or supply ships. The aerospace equipment may also encounter severe shock loadings due to pyrotechnic shock. The intensive shock causes structural failures, or even results in fatal consequences on the related facilities and persons. Therefore it is important to study the response and the damage behavior of structures under shock loading. The damage boundary of a beam under shock is studied, based on the structural dynamics and the shock response spectrum analysis. The relationship between the critical real velocity and the critical pseudo velocity is investigated, and the concept of loading factor is proposed. A simple and practical rule of estimating structure fragility is developed based on the pseudo velocity shock response spectrum and the loading factor. The explicit numerical simulation of a beam under shock loading is carried out using LS-DYNA. The critical shock response spectrums as well as the loading factor of the beam is obtained. This paper has an important significance of helping structural engineers to design the offshore and aerospace equipment under shock environment.