Development of Methods for Designing Rational Trusses

Abstract

Striving for rationality and long-term reliability is seen in different periods of building activities. Application of linear programming methods has enabled to formalise this striving and to elaborate the necessary mathematical models. But later theoretical and practical investigations have disclosed that not always, when optimising in respect of one criterion, it is possible to obtain solutions rational in other aspects, and this stimulated the application of multicriteria optimization methods. It is useful in this case to apply the ideas of the game theory, game problems solving methods already applied in other building design fields. When adapting methods of the game theory to popular needs for truss designing, a criteria set involving II alternatives has been selected. Attempts have been made to find rational truss variants by applying different methods (method of proximity to an ideal point, Wald's and Hurwitz's methods). It has been found when using the method of proximity to an ideal point for rational truss designing that a truss with a sloping brace network and pivoted knots supported by a column and composed of rectangular box shapes is more valuable than other trusses. According to Wald's and Hurvitz's methods, among popular spans of 24 m such a truss is the truss with a lowered bottom chord. Keywords: rational trusses, multicriteria optimisation, methods of Wald and Hurwitz, method of proximity to an ideal point.

New design form of steel combined roof trusses

“…Scientific and technical progress in the field of construction is closely related to the problems of development and improvement of steel structures. One of the ways to increase the efficiency of construction is the development and improvement of new progressive structural forms (Semko et al, 2020) and topology, which allows to reduce the consumption of materials, the labor intensity of manufacturing and installation, and the total cost of erecting buildings and structures, which would be competitive compared to foreign analogues (Ruiz-Teran et al, 2010). Among others, various combined steel systems, including combined roof trusses, can be attributed to such structural forms.…”

“…This article examines the actual task of choosing the main geometric parameters of a combined roof truss, the solution of which allows to identify a rational structural solution with minimal mass, achieve an efficient and economical design, and create prerequisites for the widespread use of modern combined systems. We consider such a design to be rational, which has a minimum mass, manufacturability and minimum labor-intensiveness of its manufacture (Gogol, 2018;Sinitsin, 1964;Janušaitis et al, 2012).…”

Optimization of topology of truss structures using grid computing

“…A truss includes joint elements (beams), which may have different parameters: position, length, cross-sectional area, material. Truss structure may be optimized in several aspects: sizing, shape, and topology [1,2,3,4,5]. In this paper topology optimization [6,7] is considered, where material and cross-section of beams as well as the position of immovable nodes are defined.…”

Global Optimization of Trusses With a Modified Genetic Algorithm

“…Usually the truss system includes a large number of elements (trusses), and the elements can have different parameters (length, cross-sectional area, material). Thus, truss systems can be optimized in several aspects: sizing, shape, and topology (Smith et al 2002;Janušaitis et al 2003). As the sizing and shape optimization of truss systems do not pose serious computational problems, here we will deal with the topology optimization.…”