Reliability Analysis And Optimizing Design Of Ship Unloader Structural System

These years, Continuous ship unloader has been widely used in China, because of its complicated structures, high standards of maintenance technique is required. At the same time, the fast pace development and upsizing of loading equipment necessitate better product quality and utility dependability. This paper established effective feasible program, which through the means of the finite element method, simulated sampling, orthogonal fitting and integrated automation, used simulation method and numerical method to analyize the structure system reliability in different working environments and different failure modes, and consequently realized the reliability-based optimizing design towards the structure system.Considering random factors in structure design,Created the finite element model with ANSYS, analyse structure system with stochastic finite element method. Got the response of main failure modes using Monte Carlo method, and then used its statistical function to calculate the reliability.Used response surface method to fit the surface functions, and these functions were proved to fit perfect. Consequently realized to combine FOSM with response surface method to analyse the structure system, and get satisfying results. The plan is avaliable to analyse complicated structure system reliability level. Weight method is also used to calculate system reliability.Combined with the optimization function in iSIGHT, compiled the reliability index calculation program with first order second moment method in MATLAB, took component strength reliability index, slenderness ratio of rods and system static stiffness as constraints, took minimum structure weight as optimized object to solve the structural reliability-based optimization with Multi-island genetic algorithm method. Realized the optimal distribution of structure reliability and the component optimization of. structure.Took response surface functions as substitutes of finite element functions, and took the results of FOSM solution as constraints, all of which improved the efficiency of complex structure reliability-based optimization in a large extent.