bending moment - axial force failure surface for buckleing resistant braces BRB

in order to seismic retrofitting of existing old buildings or to reform the seismic harmed buildings prefabricated buckleing resistant braces BRB are widely used. Therefore awareness of the BRB's seismic performance is in particular importance . prediction the factual behavior of BRBs against lateral loads needs implementation of nonlinear analysis and considering materials nonlinear behavior . to perform nonlinear analysis having access to details of sections failure surface is essential the failure surface of a cross section can be defined as the locus of points that correspond to ultimate strength. in this article a novel and efficient method based on fibre method concepts is presented that is usefull to calculate failure surfacesfor BRBs. moment curvature diagrams bending moment axial force interaction curves and biaxial bending axial force failure surfaces are defined by this method.

Keywords:

buckleing resistant braces , nonlinear analysis , failure surface , interaction curve , moment - curvature diagram.