Structural Optimization of 3D Trusses considering the Dynamic Effect of the Wind
Palavras-chave:
Wind Dynamic Effect, Genetic Algorithms, Finite Element Method (FEM), Brazilian StandardsResumo
In the civil engineering and construction industry there exists a consistent search for projects
that are more functional, safe and efficient. Based on those exigencies, new technologies and analysis
methods are being developed, where the common objective is to find the optimal structure in terms of
lightweight and efficiency. The use of trusses-kind structures has increased over recent years, this fact is
mainly due to its practicity in terms of structural assembly, lightness and high resistance; allowing, for
example, its use in large roof structures or stadiums. Nonetheless, an accurate analysis of its behavior
is necessary for correctly design these kind of structures. In many cases, a static analysis is sufficient.
However, in structures such as roofs or bridges, the dynamic effects could be relevant, as they can gen-
erate vibration. Resulting in discomfort for the users, or even, leading to structural failure. Thus, the
dynamic effect of the wind should be considered in order to have a more realistic behavior of the struc-
tural response. The main objective of the present work is the parametric optimization of 3D trusses,
considering the dynamic effect of the wind. The brazilian standard NBR 6123 is herewith used in order
to account for this dynamic wind effect. Restrictions are also in accordance with the brazilian standard
NBR8800, which features project restrictions for steel structures. The computational implementation
was made using Matlab programming language. The structural dynamic response was implemented
using the Finite Element Method (FEM), while the optimization procedure was accounted using the
Teaching-Learning-Based Optimization (TLBO) method. The objective function for the optimization
method is the reduction of the total weight of the structure and project restrictions were considered in
accordance with brazilian standards. Some numerical examples are presented to show the applicability
of the proposed methodology.
