极限砰击荷载下铝质船板和加筋板的变形破坏机理研究

When an aluminum high-speed ship sails under severe sea conditions, the phenomenon of ship structural slamming is significant due to large sway motions of ship. Unstiffened and stiffened plates are the most important components in ship structures, and often suffer the water slamming loadings. As the mechanical properties of materials decrease obviously in the welding heat affected zone of aluminum structures, this project aims to investigate comprehensively the plastic deformation and fracture of unstiffened and stiffened plates under extreme slamming loadings, and to compare the slamming strength to the corresponding steel structures with equivalent yield strength. According to various types of slamming loads the ship structures experience, the typical plates and stiffened plates are selected as the investigated objects, investigating comprehensively the effect of welding types on the impact strength of aluminum structures under transient slamming loads. Based on my previous works on the impact strength of ship structural components, the experiment, the finite element analysis and the simplified analytical method are used to analyze the plastic deformation and fracture of aluminum plates and stiffened plates under slamming loads, and to investigate the material mechanical properties of aluminum alloy in the welding heat affected zone, and to propose the analytical formulae for the deformation of plates and stiffened plates under transient loads. This investigation has important theoretical significance and application value for the development of structural design of new aluminum high-speed ships.

铝质高速船在恶劣海况中航行时，由于船舶的大幅摇荡运动，船体结构砰击现象尤为显著，板和加筋板作为船体结构的重要组成构件，频繁遭受水砰击压力载荷。由于铝合金结构在焊缝热影响区的材料力学性能下降明显，本项目拟对铝质板和加筋板在极限砰击荷载下的塑性变形和破坏进行全面系统地研究，并与静强度等效的钢质结构进行砰击强度对比分析。针对船舶结构在极限波浪中可能遭受的各种砰击荷载，选取典型的船体板和加筋板为研究对象，系统研究焊接形式对铝质结构在瞬态砰击荷载下的冲击强度影响。结合本人对各类船舶结构构件的冲击强度研究，运用试验、有限元分析和简化理论方法，分析铝合金板和加筋板在瞬态砰击荷载下的变形和破坏，研究铝合金在焊缝热影响区的材料力学性能，提出板和加筋板在瞬态荷载下的变形理论计算公式。本项目的研究对新型铝质高速船结构设计的研究和发展具有重要的理论意义和应用价值。

随着社会经济的发展，对游艇的需求不断增长，而铝合金游艇凭借其材料重量轻、耐腐蚀性能强、使用寿命长和便于维护等优点，受到了消费者的青睐。当铝合金游艇在海洋极端环境中高速航行时，其遭受的极限波浪载荷对船体结构设计提出了巨大挑战。由于铝合金结构在焊缝热影响区的材料力学性能下降明显，严重影响船体结构的强度。本项目着重对铝质板和加筋板在极限砰击荷载下的塑性变形和破坏进行全面系统地研究，并与静强度等效的钢质结构进行砰击强度对比分析。针对船舶结构在极限波浪中可能遭受的各种砰击荷载，选取典型的船体板和加筋板为研究对象，研究焊接形式对铝质结构在瞬态砰击荷载下的冲击强度影响。各类舶结构构件的冲击强度研究，运用试验、有限元分析和简化理论方法，分析铝合金板和加筋板在瞬态砰击荷载下的变形和破坏，研究铝合金在焊缝热影响区的材料力学性能，提出板和加筋板在瞬态荷载下的变形理论计算公式。.项目按照原定计划，严格按照经费使用要求列支，圆满完成所有研究目标。项目的研究成果丰硕，可为铝合金游艇设计提供结构强度评估技术，也可为军用高速艇等高性能船舶的极限状态设计提供有力的理论与技术支撑。