Simplified P-Delta Analyses for Asymmetric Structures

Computer oriented and manual procedures are presented that enable a direct second order analysis of asymmetric building structures to be performed by means of first order formulation. This is achieved by modeling the geometric-stiffness of the structure as a fictitious column with negative lateral and torsional stiffness properties. Simplified methods are proposed for structures amenable to some form of uncoupling. The approach is also applied to elastic-plastic analysis of asymmetric structures by combining center-of-rigidity and sway-subassemblage procedures. A numerical example is provided.