An analytical model for bottom plate torn by a cone-shape rock during ship grounding accident
ZENG Jia1,2,HU Zhi-qiang1,3,CHEN Gang1,2
1. State Key Laboratory of Ocean Engineering, Shanghai 200240, China;
2. State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian 116024, China;
3. Marine Design and Research Institute of China, Shanghai 200011, China
Abstract:A theoretical method for plate tearing by a rigid cone is developed in this paper. The studied model is an idealization of ship grounding damage. The observed mode of deformation is idealized by a simplified, kinematical admissible deformation mode, and the rate of internal energy dissipation in friction, stretching, bending and fracture is quantified accordingly by analytical expressions. Based on the Upper-bound theorem, the plate tearing resisting force in the moving direction of the cone can be calculated by the proposed analytical formula. The analytical formula is compared to a series of Muscat-Fenech experimental results, and agrees reasonably well with the results. Non-linear finite element program LS_DYNA was used to simulate several grounding scenarios of a typical ship double bottom structure running aground on a cone-shape rock. By adopting equivalent plate thickness, the analytical method proposed was verified with the simulation results. The analytical calculation formula obtained could be used to calculate and assess the crashworthiness of a ship during its design phase.
曾 佳1,2,胡志强1,3,陈 刚1,2. 船底板被圆锥形礁石撕裂变形的机理研究[J]. 振动与冲击, 2015, 34(16): 66-72.
ZENG Jia1,2,HU Zhi-qiang1,3,CHEN Gang1,2. An analytical model for bottom plate torn by a cone-shape rock during ship grounding accident. JOURNAL OF VIBRATION AND SHOCK, 2015, 34(16): 66-72.
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