Abstract: The fatigue failure of steel crane beams has caused many safety accidents and has become one of the hot issues in the field of industrial buildings. A right-angle crane beam is the most common form of crane beams. In order to study the fatigue damage mechanism and reinforcement method of right-angle crane beams and improve the fatigue resistance of traditional steel right-angle crane beams, the reinforcement measures of one three-web structure are proposed on the basis of clarifying the stress concentration position of a crane beam support. Through finite element simulation analysis and experimental research, the reinforcement effect of the setting method and the three-web structure on the cracked bearing is explored; the structural stress distribution along the weld length at the stress concentration position before and after reinforcement at the support is analyzed, and the reinforcement effect of the three-web structure is verified. The study results show that compared with the traditional right-angle bearing, the maximum structural stress at each position of the three-web bearing decreases by 60%, and the stress intensity factor at the crack decreases by about 50%; The fatigue life of crane beam can be greatly increased under both no cracked and cracked conditions.