They used fully stress design method for the optimization of cross section and conjugate gradient method for optimization of coordinates.
Lluis Gil and Antoni Andreu (2001) presented a method to give optimum shape and cross section of a plane truss by considering stress constraints and geometrical constraints. Hopkins (1998) presented a paper on fully stressed design by use of analytical and graphical methods and by taking displacement constraints. They have given a formulation to solve number of problem to give optimal member size and member layout by giving location of joints and loads. Rossow (1977) presented calculation on optimal design of trusses by considering design variables as constraints and optimally criteria based on strain energy considerations. Ohsaki (1995) carried out a study on optimization of trusses considering displacement and stress constraints in different static loading condition by using the concept of genetic algorithm. He investigated on finding optimal spacing of roof truss of a given span and length to get optimum weight. Rajasekaran (1983) has carried out research on optimal design of industrial roof system by using computer aided technique. Templemen (1983) explained the reason why only some research output could be applied to designing. Brown (1977) presented an algorithm which covered application of optimization method for roof truss system considering the cost function as parameter.
Method is useful in solving discrete member spectrum which included behavior of members. Agrawal (1974) proposed a complex method of optimization in which geometric and topological variable were included. William Prager (1976) discussed the optimal design of truss which had bars and connected to loaded joints on a horizontal ceiling where single and two alternative loads were considered. This study considered problem of determining optimal member sizes which minimized weight of a pin jointed truss of fixed geometry which satisfied certain constraints. Templemen (1976) introduced theories of dual approach in his paper which showed the implication and usefulness of dual approach. In past, many researchers had carried out research on optimization of truss.Īndrew B. Some of the basic optimization techniques are: Mathematical programming, Optimality criteria, Approximation methods and Fully Stressed Design method. The optimum shape of a truss depends not only upon its topology, but it also depends on distribution of element cross-sectional areas. The optimum design of a structure should satisfy various constraint limits, and stress and local stability conditions. Hence, it becomes necessary to optimize the structure to fulfill the economical requirement. In any case of construction of structure, the main objective is to reduce the cost of the project and fulfill structural requirement. The sections used for steel trusses are generally angle sections, square hollow sections, pipe sections, T-sections, C-channel sections, etc. These days, most of the trusses are made of steel, however, in some cases timber and concrete trusses are also utilized. Steel trusses are most widely used in industrial buildings. Trusses have a high use in modern construction and are used commonly in buildings where support to roofs, floors and internal loadings is readily provided. Hence, truss members carry only axial forces which are either in compressive or tensile in nature. Joints in truss carry zero moments since members are connected by frictionless pin. Elements in a truss are arranged in such a pattern so that they produce an efficient, light weight, load-bearing members.
Each member in a truss is straight and is connected at joints. A truss is a structural object comprising of a stable and systematic arrangement of slender interconnected members.
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