基于断裂力学的破冰船结构疲劳损伤评估方法  

Fatigue Damage Assessment Method for Icebreakers Based on Fracture Mechanics

作　　者：赵伟栋 冯国庆 陈占阳[1] 张岩[1] 桂洪斌[1] ZHAO Weidong;FENG Guoqing;CHEN Zhanyang;ZHANG Yan;GUI Hongbin(Harbin Institute of Technology(Weihai),Weihai 264209,China;Harbin Engineering University,Harbin 150001,China)

机构地区：[1]哈尔滨工业大学(威海),威海264209 [2]哈尔滨工程大学,哈尔滨150001

出　　处：《中国造船》2023年第3期56-67,共12页Shipbuilding of China

基　　金：山东省自然科学基金青年项目(ZR2022QE092);船舶总体性能创新研究开放基金(32122226);国家自然科学基金面上项目(52171301)。

摘　　要：在极地恶劣的低温环境及冰载荷冲击下,破冰船结构的表面裂纹呈现出不同于常规水面船舶的疲劳裂纹扩展特性。以“雪龙2”号破冰船首部结构为例,基于断裂力学方法开展破冰船结构节点处的疲劳裂纹扩展研究。首先基于焊接节点处应力强度因子的理论解,对表面裂纹扩展方法进行验证;然后通过整体-局部耦合分析方法提取典型疲劳节点处的结构子模型。基于低温下材料的Paris参数和结构裂纹扩展模拟方法进行裂纹扩展分析。还讨论了初始裂纹尺寸和低温下材料的Paris参数对结构裂纹扩展的影响。结果表明,破冰船典型结构节点处的裂纹扩展对初始裂纹尺寸和温度较为敏感。In the extremely low-temperature environment of the polar region,with the impact of ice loads,surface cracks within the icebreaker structure exhibit fatigue crack growth characteristics different from that observed in conventional surface ships.Bow structure of the Xuelong 2 icebreaker was applied to illustrate the proposed research approach.Propagation of the fatigue crack at the structural points of the icebreaker is studied based on the fracture mechanics.The propagation method of surface crack is verified based on the theoretical solution of the stress intensity factor at welded joints.Through the global-local coupling analysis,structural sub-models are extracted with respect to typical fatigue points.Crack propagation simulation of the icebreaker is carried out.Effects of initial crack size and low-temperature Paris parameters on the crack propagation of cracked structures in icebreakers are discussed.The results show that the crack propagation behavior at typical structural points of an icebreaker is sensitive to the initial crack size and low-temperature.

关 键 词：断裂力学 破冰船 低温 应力强度因子 裂纹扩展 疲劳损伤 

分 类 号：U661.4[交通运输工程—船舶及航道工程]