CAJ | 학술논문

疲劳是船舶、海洋工程和桥吊等钢结构的主要破坏机理之一.影响疲劳裂纹成长的因素具有随机性质.用Paris定律描述疲劳的扩展,假定疲劳裂纹初始具有半椭圆形状,且在裂纹扩展中保持着半椭圆形状.失效准则采用在具有N次应力周期的给定时间中裂纹超过临界尺寸.用Paris定律,结合改进的Ⅱ水平方法,对不同初始裂纹对断裂破坏的可靠度进行了分析计算.
피로시선박、해양공정화교조등강결구적주요파배궤리지일.영향피로렬문성장적인소구유수궤성질.용Paris정률묘술피로적확전,가정피로렬문초시구유반타원형상,차재렬문확전중보지착반타원형상.실효준칙채용재구유N차응력주기적급정시간중렬문초과림계척촌.용Paris정률,결합개진적Ⅱ수평방법,대불동초시렬문대단렬파배적가고도진행료분석계산.
Fatigue is one of the failure mechanisms of ship, offshore and bridge crane steel structures. The factors influencing the fatigue crack growth are of random nature. The Paris law is used for the description of crack propagation. It is assumed that the fatigue crack initially has a semi-elliptical shape, and that the shape remains semi-elliptical as the crack propagates. The failure criterion is taken as exceedance of a critical crack size in a time period with N stress cycles. To simplify the problem the thickness of plate is chosen as the critical size. Then using the Paris' law in conjunction with an advanced Level Ⅱ method, the reliability of fracture failure is examined.