Resumo

DIAZ MARTINEZ, Gerardo  e  SORDO ZABAY, Emilio. Efecto de la transición al mecanismo plástico en la inestabilidad dinámica. Ing. sísm [online]. 2011, n.85, pp.33-59. ISSN 0185-092X.

This paper focuses on the variations of the dynamic collapse coefficient (Cc) produced by differences in the characteristics of mechanism development. The Cc is thus obtained firstly for a group of frames having in common elastic properties, ultimate base shear strength and collapse mechanism when subjected to different ground motions, then, for a group of single degree of freedom systems. Records are classified by soil type and epicentral distance. Results for frames show differences close to 50% in Cc, depending on the mechanism development characteristics. On the other hand, collapse spectra are computed for trilinear single degree of freedom systems subjected to the same set of records. From these spectra, it can be concluded that systems with bilinear behaviour always lead to conservative values of the dynamic collapse coefficient.

Palavras-chave : dynamic instability; plastic mechanism; instability index.