Graph based discrete optimization in structural dynamics

Abstract

Abstract. In this study, a relatively simple method of discrete structural optimization with dynamic loads is presented. It is based on a tree graph, representing discrete values of the structural weight. In practical design, the number of such values may be very large. This is because they are equal to the combination numbers, arising from numbers of structural members and prefabricated elements. The starting point of the method is the weight obtained from continuous optimization, which is assumed to be the lower bound of all possible discrete weights. Applying the graph, it is possible to find a set of weights close to the continuous solution. The smallest of these values, fulfilling constraints, is assumed to be the discrete minimum weight solution. Constraints can be imposed on stresses, displacements and accelerations. The short outline of the method is presented in Sec. 2. The idea of discrete structural optimization by means of graphs. The knowledge needed to apply the method is limited to the FEM and graph representation.The paper is illustrated with two examples. The first one deals with a transmission tower subjected to stochastic wind loading. The second one with a composite floor subjected to deterministic dynamic forces, coming from the synchronized crowd activities, like dance or aerobic.

Fully decoupled reliability-based optimization of linear structures subject to Gaussian dynamic loading considering discrete design variables

“…The first one involves direct coupling of algorithms for discrete optimization and reliability analysis, as proposed in, e.g. [21,22,23,24,25,26]. The second class of approaches consists of constructing a surrogate model for reliability, thus rendering the application of the optimization algorithm trivial, see e.g.…”

Minimum weight design of composite floors under human induced vibrations

“…Constraints were imposed on stresses, displacement and accelerations. According the algorithm presented in paper [3], in order to find minimum weight of the composite floor the following steps have been proceeded:…”

“…In this paper, an alternative approach has been proposed. It is based on graph representation of the structural optimization problem and is described in detail in previous authors' papers [2,3].…”

Recent developments in simulation-driven multi-objective design of antennas

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