Research On Fatigue Performance Of Crane Beam After Prestressed Reinforcement

Variable cross section is often used to save steel for crane beam member in steel structure factory building due to different column spacing.The curved seal plate right-angle abrupt crane beam is a kind of variable section crane beam,which was originally applied in the first phase project of Baosteel to replace the circular arc transition crane beam with fatigue crack.This type of crane beam was introduced,but after 14 years of service,fatigue broke.This paper mainly focuses on the research of the fatigue performance of the crane girder after the prestressed reinforcement in the industrial plant.In this test,combined with the previous research on the fatigue performance of right-angle catastrophic crane beams by the MCC Architectural Research Institute,the prestressed reinforcement steel crane beam technology research was carried out.The details are as follows:Firstly,the basic theory of fatigue failure of welded structure and the method of fatigue strength evaluation of welded structure are described.This paper summarizes the engineering cases and scientific research results of prestressed reinforcement of steel crane girder,explores the technical system of prestressed tensioning for steel crane girder,and designs the test scheme of prestressed reinforcement of steel crane girder.Then,carry out the fatigue test of the prestressed steel crane girder,compare the fatigue failure characteristics of the crane girder before and after the reinforcement and the detailed characteristics of the weld cracking,and analyze the reinforcement effect after introducing the prestress.According to the test results and numerical simulation results,the stress changes and deflection changes of the crane beams before and after the prestressed reinforcement are compared.Finally,right-angle mutational crane beam model is established by ABAQUS,calculation of the prestressed reinforcement steel crane beam after the static bearing capacity and stability,then import the stress calculation results obtained in FE-Safe equivalent structural stress,and basic parameters it is concluded that the main structure of equivalent stress S-N curve of crane beam to the natural cycle of life and quantitative study of the fatigue performance of the crane beam before and after reinforcement.Through fatigue scale model test,finite element analysis and engineering simulation analysis,the variation range of the life of right-angle mutational crane beam before and after prestressed reinforcement is obtained,and the engineering applicability of equivalent structural stress theory for the fatigue analysis of right-angled cataclute crane beam is verified.The work of this paper can develop the fatigue diagnosis and treatment technology of right-angle catastrophe steel crane beam system in industrial plant,so as to reduce the cost of fatigue reinforcement of steel structure in industrial building and improve the safety guarantee of industrial production.