A Review of Nonlinear Static Analyses of Planar Steel Frames

Abstract

For several years, alignment charts and moment amplification factors were the basis for design of columns and beams subjected to combined loadings. However, in recent years, research has been devoted to developing a rigorous second order analysis computational framework. While many commercial software now provide embedded second order facility, many designers still lack the theoretical and more importantly, the algorithmic know how of the machinery behind these software. Our research goal is to unravel this machinery right down to its algorithmic detail so that a structural analyst can understand the assumptions, limitations and nuances of nonlinear analysis. The objective of this study is threefold: First, to give a detailed insight into the nonlinear analyses, while creating a MATLAB learning suite, to help with the understanding of the subject. We will use MASTAN2 for the verification of our codes. Second, to equip the future researchers with the preliminary knowledge required in the more active areas of research. And third, to aid the engineers working in the field by familiarizing them with the rigorous second order analysis for a more accurate stability design. MATLAB codes were developed and verified for the critical load analyses and the load deflection analyses while providing a detailed explanation of the algorithmic procedures involved along with the flowcharts. This study will serve to develop a sound understanding of the basics of steel stability for the new researchers and will help in acquainting the design engineers with rigorous second order analysis.