Research On Reliability And Global Sensitivity Of Metal Structure Of Bridge Crane

As a large-scale material handling equipment,bridge crane is widely used.Its safety and reliability directly affect the probability of accidents.Bridge structure is the skeleton of crane,and its structural reliability determines the safety of machine operation.In previous reliability methods,the efficiency of small failure probability and complex structure is low.Therefore,considering the sufficient sample data,low failure probability of structure and the complexity of limit state function,this paper constructs a reliability analysis method of adaptive surrogate model based on probability density.At the same time,considering the lack of influence evaluation on variable parameters in the actual bridge crane structure safety design,the calculation framework of reliability global sensitivity of bridge crane structure is proposed.The detailed work is as reads:(1)According to the working characteristics of bridge crane,the failure criteria of strength and stiffness are given,and the limit state function in failure analysis is determined.Due to the shortcomings of complex form and large amount of limit function calculation,an adaptive surrogate model structural reliability algorithm is proposed.The efficiency and accuracy of the method are tested by four simple examples.(2)Aiming at the information quantification of the influence of variable parameters on failure probability,a calculation framework of reliability global sensitivity of bridge crane structure is proposed.The framework includes the analysis of two failure modes of bridge crane structure and the calculation of variable global sensitivity index under the corresponding failure mode.The evaluated parameter variables include: load,structural size and material properties.(3)Based on the joint simulation of MATLAB and APDL,the quantitative influence of structural parameter variables of bridge crane on failure probability is calculated.The stress calculation and verification of the main beam structure finished by the simulation algorithm,and analysis the failure probability of crane structure under two failure modes.Through the verification of engineering examples,the failure probability of bridge crane under the influence of parameter variables is obtained.At the same time,it is concluded that uncertain load variable wheel pressure and uncertain size variable web thickness have a great influence on structural failure.