Optimal Desing of Composite Box-Type Structures

Abstract

The present paper considers the optimization methods of box-type thin-wall structures both in terms of materials and in terms of calculation methods. These structures are widely used in transport, construction and other areas. The example of such structures are bodies of buses, trolleybuses, trams, camper vans, train carriages, emergency vehicles, mobile workshops, accommodation facilities and others. At first global and later local optimization for the preset exposure by system analysis, mathematical modelling and IT-technologies were performed. Determination of global target function and optimization criteria, global and local limitations is shown during optimization. Development of a box-type composite thin-wall structure project was suggested including geometric simulation, selection of material components and whin-wall elements composition. For the purpose of comparison application of nature biological organism for combination of composite panel by separation of principal organ systems providing its vital activity: a locomotive, circulatory, inspiratory and etc., was described. It was shown that similarly to an organism a vehicle (non-uniform system) can provide general and local strength and rigidity of structural elements. When composing a thin-wall element, each variant of a panel is considered as a module with its physical and mechanical characteristics. Methods that can be applied to nonuniform structure analysis and formulae to determine the given flexural rigidity of plate and shell elements of “equivalent” uniform material are described further. An example of box-type thin-wall composite structure optimal design was shown. The conclusion with regard to the proposed method of optimal analysis and design of composite thin-wall structures is made by means of system approach.