Unimodal formulation of the analysis and design problems for framed structures

Traditionally the analysis of framed and trussed structures is carried out along similar, albeit different, paths. This is true chiefly in the force approach. The difference is to be attributed to the truss element having essentially one deformation mode, whereas bending elements are bimodal. It is shown that by means of an eigenvalue analysis, a uniform Timoshenko bending element can be decomposed into its constituent unimodal components. Consequently, frame and truss analysis are united into an identical set of equations, and solution techniques. Such an approach is shown to be beneficial, even for the automated design of framed structures. (C) 1997 Civil-Comp Ltd and Elsevier Science Ltd.