NONLINEAR TRANSIENT ANALYSIS OF PLANAR STEEL FRAMES WITH SEMI-RIGID CONNECTIONS
Everton A. P. Batelo1; Andréa R. D. Silva1; Ricardo A. M. Silveira1
1 UFOP - Universidade Federal de Ouro Preto
doi:10.20906/CPS/CILAMCE2015-0758
Resumo
For all steel structural construction that involves one or more floors, the use of beam-column or even column-base connections is inherent. Due to their importance, these connections are, in steel structures, economically and structurally significant. Also in some situations, these steel buildings are subjected to a dynamic load level that can cause permanent deformation and localized damage in the structure, and this may lead to its partial or total collapse. To obtain a more realistic prediction of the behavior of steel structures, the flexibility of the connection between the members should be considered in the analysis. This work aims to evaluate the nonlinear behavior of steel frames structures under dynamic loads, showing the influence of the semi-rigid connections in response of the structure, and also exploring the structural hysteretic damping. The modeling strategy used is based on the Finite Element Method application, and the transient nonlinear solver adopted combines the methods of Newmark and Newton-Raphson. At the end of the work is carried out a numerical study of a four-bay five-story planar steel frame with beam-column semi-rigid joints. From the analysis, it will be possible note that the flexible connections flexibility has significant influence on variation of the natural frequencies, particularly on the lower frequencies and on the frame nonlinear behavior.
Palavras-chave: steel frames; nonlinear transient analysis; geometric nonlinearities; semi-rigid connections; hysteretic damping