Effective Buckling Length Analysis in Steel Frame Columns: A Comprehensive Review and Novel Approaches

This paper provides a comprehensive review of the effective buckling length analysis of columns within steel frames, drawing insights from various sources, including building codes, traditional analysis methods, and advancements in computational techniques. The focus is on the influential, effective length factor, a crucial parameter shaping column buckling behavior and, consequently, the overall structural design. Building upon empirical classifications in building codes, the paper scrutinizes the challenges associated with lateral restraint classifications. Advancements in computational techniques are delineated, from traditional alignment charts to proposed closed-form equations for effective length factors. A method based on finite element analysis is suggested to address buckling issues and determine the effective buckling length. The Euler beam finite element, which includes the von Karman deformation, is presented and used in numerical analysis to obtain the buckling length. Also, a correlation is given between Eurocode’s elastic restraint coefficients and the stiffness of the rotational spring. The spring is used to model restraints at the column’s ends.