Design procedure for failure mode control of linked column frames

Abstract

This paper investigates the seismic behaviour linked column frames (LCFs). This structural system, traditionally, consists of moment frames for the gravity loads and dual columns interconnected with bolted links for the horizontal actions. An optimized design approach is herein developed for the LCFs according to the Theory of Plastic Mechanism Control (TPMC) through a closed form solution assuring the maximum energy dissipation, i.e., the development of a collapse mechanism of global type. Several structural schemes are designed according to the proposed design approach considering different geometry, link length and structural height. The accuracy of the TPMC is evaluated through nonlinear static and dynamic analyses. In particular, the dynamic analyses are developed for a selection of designed fames to highlight the difference in terms of performances among the structures with short, long and intermediate links.