中文摘要：

为研究起升载荷下门式起重机主梁的损伤和疲劳寿命,通过有限元软件ANSYS Workbench建立门式起重机主梁力学模型,采用nsoft疲劳分析软件对主梁的动静态力学特性和疲劳损伤进行了分析,采用nCode GlypWorks中的Rainflow模块对各载荷作用的应力时间历程进行雨流计数、载荷外推和叠加,采用nCode GlypWorks中的Stress Life模块计算主梁的疲劳寿命以及敏感性分析,得到不同工况下门式起重机箱型主梁应力和应变云图以及叠加后雨流直方图、主梁损伤直方图、裂纹—寿命关系曲线.研究结果表明：主梁的最大等效应力位置在跨中或端部以及主梁与支腿连接部位,易产生疲劳损伤;40t以上起重量是造成主梁损伤主要载荷;过载、残余应力和表面粗糙度均对主梁的使用寿命具有明显影响.冲击损伤仿真结果与计算结果较为接近,说明冲击损伤计算结果具有较高的可信度.

英文摘要：

In order to study the damage and fatigue life of gantry crane＇s girder under rising load,the mechanical model of gantry crane＇s girder was established through the finite element software ANSYS Workbench,the dynamic and static mechanical properties and fatigue damage of girder were analyzed by using fatigue analysis software nsoft,the rain flow counting,the extrapolation superstition of the stress time on load were carried out by using Rainflow module in nCode Glyp Works.The life stress module in nCode GlypWorks was used to calculate the fatigue life and analyze the sensitivity of girder,through which the stress and strain image,superimposed rain flow histogram,girder damage histogram and crack-life relationship curve of gantry crane chassis type girder were got.The results showed that,the maximum equivalent stress positions appeared in the middle or end of the girder,the joints of girder and legs where were easy to produce fatigue damage;the lifting capacity that more than 40 twould significantly cause the damage of the girder;overloading residual stress and surface roughness had a significant impact on the life of the girder.The simulation results of impact damage are close to the results of calculation which illus-trates that the results of impact damage have certain credibility.