钢吊车梁加固前后受力性能试验研究

The Experimental Study on Mechanical Properties of Steel Crane Girder Before and After Reinforcement

以某厂工字形带裂缝的钢吊车梁为研究对象,在对国内外开裂钢吊车梁疲劳损伤进行广泛调查研究的基础上,提出了以提高吊车梁上部区域有效面积和刚度为目的的加固方案。通过吊车梁加固前后200万次疲劳试验,对加固前后裂缝尖端主应力的大小及方向的变化规律进行了研究。研究结果表明:通过增大截面有效面积及刚度可以延长开裂钢吊车梁的疲劳剩余使用寿命,对实际工业厂房中存在开裂的钢吊车梁的加固及维护有很好的指导意义。

This paper focuses on a cracking steel crane girder of one factory.On the basis of extensive investigation and research on the fatigue damage of cracking steel crane girder at home and abroad,in order to improve the effective area and stiffness of the upper area of the crane girder,a reinforcement program is put forward.Through 2 million times fatigue test of the crane girder before and after reinforcement,this paper researched on the change rules of magnitude and direction about the crack tip principal stress before and after reinforcement.The results show that it can extend the fatigue remaining service life of fatigue cracking of the steel crane girder by increasing the effective cross section area and stiffness,and it is a good guide on reinforcement and maintenance of actual industrial plant cracking steel crane girder.