Analysis Of Reliability And Optimum Design Of Truss Structure

The work is associated with truss structural system in practicable engineering, the limiting state equations regular service limit state of structures is given based on the reliability principle. The paper discusses the computational method of reliability for truss structures which is acquired under the bar buckling by assuring enough lateral support in outside plane. On the basis of the geometrical meaning of structural reliability index, a model for structural reliability analysis under conditions of normal random variables and abnormal random variables is established. Having made a calculation of the actual engineering, the results indicate that the influence of the bar buckling can not be ignored when the reliability for truss structures is calculated. The reference to the computational method for reliability of similar truss structures is provided.The problem of optimization of truss structures based on reliability is studied in this paper. The mathematical model of optimization based on reliability for truss structures is given, in which the cross sectional areas of bar are taken as design variables , the structure weight is taken as objective function , both the reliability of structural displacement and bar stress are taken as constraint functions. The problem of minimum weight design with the constraint of structural system reliability is solved. Finally, the example is given, and the evaluated results demonstrate that the method presented is effective and feasible. The reference to the computational method for the optimization design based on reliability for similar truss structures is provided.