Analysis of Multiple-Bay Frames Using Continuum Model

An approximate method that can be used to determine displacements and member forces of multiple-bay frames is presented. The method utilizes simple continuum models. Finite-element representations of building frameworks resulting from continuum methodology require significantly fewer degrees of freedom than classical discrete finite-element models, which individually model each of the beam and column elements. As a result, the use of continuum models to analyze structures can result in considerable savings in terms of computational effort. This makes the method attractive for use in the analysis of large frames, especially during the preliminary design stage. This paper reviews the continuum methodology and presents a method for computing discrete element forces from the continuum element displacements. In determining element forces, the effects of deep-beam-type cross-sectional warping are approximated. Examples including the analysis of fixed- and pinned-base single- and multiple-bay plane frames illustrate the accuracy of the continuum analyses procedure.