The Performance Analysis On The Crane’s Hyper-static Beam System After Local Buckling

Hyper-static beam system is always used in large and tall cranes. It has the advantages in the structural lightweight, high torsion stiffness and bending stiffness, but the local buckling will easy to occur before the instability of the whole structure. Thus affects the overall structure subsequent strength, stiffness, stability and other related performance. But the performance analysis on the hyper-static beam system always ignores the post-buckling effect. In this paper, studies the change of the internal force redistribution and structural configuration after local buckling in depth. Then analyzes the mechanical properties after the local buckling and gives out the effective measures.Firstly, the conventional method of performance analyzing on the hyper-static beam system is discussed. It uses the accurate finite element method considering the axial force effect to integrate the general hyper-static beam system’s stiffness and gives out the instability discrimination. After that, it analyzes the limitations of the common method of the performance analysis on the hyper-static beam system through the conversion slenderness ratio and the instability discrimination which are given by the equivalent length method and the finite element method. The typical hyper-static beam system is analyzed in the module of eigenvalue buckling analysis in the finite element software to observe the local buckling phenomenon and analyze the effect of local buckling on the overall structure. The limitations of the finite element method are further analyzed by this method.Establishes reasonable mechanical model and gives out the local buckling beam’s instability discrimination though the accurate finite element method considering the axial force effect. Through the axial force search method to search the local buckling beam. The axial force search strategy is discussed and gives out the rapid method for predicting the order of the local buckling beams. After searching the local buckling beam, through the unit replacement method and the equivalent mass method to rebuild the mechanical model. It can solve the limitation of the traditional performance analysis method on the hyper-static beam system and provides a new performance analysis method on the hyper-static beam system after local buckling.The research of the typical hyper-static beam structure’s performance is studied by the axial force search method and the model reconstruction method. Though the improving linear and exact finite element method pulls the theory of the typical hyper-static beam structure’s static and dynamic performances after local buckling. Then, analyzes the change of the hyper-static beam structure’s static and dynamic performances when it occurs the local buckling, in order to ensure the real hyper-static beam structure’s accurate bearing capacity and performance. The results are extended to the hyper-static beam system. It provides the theoretical basis for analyzing the change of the hyper-static beam system’s performance after local buckling.According to the research on the performance of the typical hyper-static beam system, develops a special program based on ANSYS platform to analyze the performance on the hyper-static beam system which considers the local buckling effect. It can predict the order of the real structure’s local buckling beams, get the change performance of the hyper-static beam system and the structure’s accurate bearing capacity. The correctness of the theoretical results are verified by the procedure, and the performance analysis of the QTZ100 tower crane is carried ou t based on local buckling.