Analysis of the Lateral Thrust in Bolted Steel Buckling-Restrained Braces. I: Experimental and Numerical Results

Abstract

This work presents an experimental and numerical analysis of the lateral forces exerted by the inner core of a buckling-restrained brace (BRB) when, after buckling in compression, it arrives into contact with the external restraining case, from which it is separated by a small empty gap. Experiments are carried out on reduced-scale specimens to measure the thrust acting on the containment struts. Refined, nonlinear two-dimensional (2D) FEM models are adopted to obtain numerical estimates of the thrust. The results show (1) the capability of 2D, plane stress FEM models to correctly reproduce the cyclic behavior of the studied BRBs, and (2) the difficulty in accurately measuring/computing the thrust associated to a given axial load/displacement.