THE MOMENT-DISTRIBUTION METHOD FOR STATICALLY INDETERMINATE BEAMS USING THREE DIFFERENT MODELS

摘要

This paper presents the Moment-Distribution Method (method of successive approximations) for statically indeterminate beams using three different models: the Model 1 considers the bending deformations and shear in the methodology, and also in the fixed-end moments, and this is the innovative part of this paper; the Model 2 takes into account the bending deformations and shear in the methodology, and in the fixed-end moments considers only the bending deformations; the Model 3 is the classical model called Hardy Cross method, which considers the bending deformations in the methodology and also in the fixed-end moments. Also a comparison is made between the three models through three different problems for lengths of 5.00, 7.50, 10.00 m to observe differences. The results show the differences between the three models, and when members tend to be shorter, the differences are increased in proposed model (Model 1) with respect to the other two models. Therefore, for the normal practice of using the Model 2 and Model 3, these are not a recommended solution, when lengths are short between supports. Then, the Model 1 (proposed model) passes to be the more appropriate model for structural analysis of continuous beams using the Moment-Distribution Method (method of successive approximations) and also is adjusted to the real conditions, since the shear forces and moments are presented in any analysis of continuous beams, and the bending deformations and shear appear.