不同结构形式箱形框架疲劳寿命研究

箱形框架结构在机械行业中应用广泛,不同形式框架结构对外载荷承载能力不同。以三种箱形框架为对象,分别研究其在同种载荷作用下的抗疲劳性能,并对结构的疲劳寿命进行对比分析,总结得出,3种框架结构疲劳强度依次为模型3最大,模型1次之,模型2最小。模型1的上侧焊接接头焊根处为疲劳易破坏位置,模型2的下侧焊接接头焊喉处为疲劳易破坏位置,模型3的焊接接头焊趾处为疲劳易破坏位置。该疲劳寿命分析预测方法,计算精度高,适用范围广,对复杂焊接结构的疲劳寿命预测有重要意义。

Box frame structures are widely used in machinery industry. The external load bearing capacity of different forms of frame structure is different. Taking three kinds of box frame as the object, the anti-fatigue performance under the same load is studied respectively, and the fatigue life of the structure is compared and analyzed. It is concluded that, the fatigue strength of three kinds of frame structures is the largest in Model3, followed by Model1 and Model2. The upper weld root of Model1 is the position where it is easy to be damaged;the lower weld throat of Model2 is the position where it is easy to be damaged;and the weld toe of Model3 is the position where it is easy to be damaged. The fatigue analysis and prediction method has high calculation accuracy and wide application range, which is of great significance to the fatigue life prediction of complex welded structures.