Limit analysis of 3D building structures

Abstract

In this work, a limit analysis of typical building frames is carried out, and the collapse load and collapse mechanism of 3D frames composed of slender steel structural elements under concentrated and uniformly distributed loads are calculated. To this end, the direct kinematic method and nonlinear optimization techniques are proposed to search for the collapse mechanism and determine the collapse load. This work has the advantage that the structure’s equilibrium equations are obtained through a completely systematic formulation of the problem of interest. In many cases, the case of uniformly distributed loads is simplified by equivalent point loads. However, this work verifies that the results differ in the cases of point loads and uniformly distributed loads, both qualitatively and quantitatively.