The Elementary Discuss Base On The Optimize Question Of The Structural Reliability On GA

With the increasingly large-scale and complex on engineering structure the infection on design parameter of structural capability became more and more , and the restrict condition more rigor and complex at the same time, the demand on the stabilization on the structure become more and more strict, and the traditional design method make the period on design longer and be hard to let many design parameter make the right choice. Which gain the structural integration capability can not to the intending state, but optimize design not only reduce the weight of structure and the cost on material but also improve the intensity vibration and stability on structure and make the structure at the maximum fulfill the demand on the economic and the safe, therefore possess the important value on apply.So far, the optimize design on structure has hundreds of history, especially over the past forty years. It has make many progress on theory and arithmetic and the application, but the history on the optimize design of the reliable structure is not long. This thesis mean think about the optimize question on joist. At first it set up the math model that think cross section as variable and think the ethereal weight as optimize objection and think the reliability index optimize restrict condition. Though the analysis on traditional and optimize method and gain the quadric derivative through reliability index and get the Hessa matrix, find the reasonable and reliable index, traditional method is applicable, but it is not apply for the lesser reliable index.Basal difficulty on the optimize question of reliability is that when the system optimize the parameter, variable, must evaluate and must calculate the reliability once more. This thesis base on PNET, analyze the reliability on structural system and get the reliability index analyze the design variable and get the accurate expression, on sensitive analyze. Base on this we put up the lest weight design under reliability restrict on structural system.Face on the defection on traditional method, we have the analyze on the fashionable and evolutional arithmetic, at last , we choose GA as the main arithmetic of optimize design, GA base on natural selection and colonial genetics, which has the extensive application. And has the entire astringency, GA has the potential optimize arithmetic, this thesis give the lest weight' s design result under the reliability restrict.