Effective Length Spectra for Cross Bracings

Abstract

General effective length criteria for cross‐bracing systems are formulated. The criteria entail closed‐form analytic relationships for evaluating compression brace critical load and effective length factor K with due consideration of the relative stiffness and end conditions of the tensile diagonal. Effective length spectra curves are generated to elucidate the criteria and to facilitate design application. Results indicate that the effective length is very sensitive to the relative stiffness of the two interconnected diagonals and, depending on brace end conditions, the effective length factor values range from 0.35 to 1.0. Refereed experimental data available in the range agree well with the proposed solution. Application of the criteria will lead to an optimum design and enhance overall structural stability.