LOAD DISTRIBUTION IN GIRDER BRIDGES BY DIFFERENT METHODS

Abstract

Girder bridges which are generally simply supported have been found to suit the small and medium span coverage both from point of view of structural efficiency of the deck behaviour as well as ease of construction and economy. Both conventional as well as computer based methods of analysis for girder bridges are available. Some of the conventional methods are briefly presented in the various chapters of this dissertation. These methods are (1) Courbon's T.Iethod (2) Orthotropic Plate theory based (a) Morice, Little and Rowe curves ; and (b) Cusens and Pama curves ; and (3) Harmonics method. The assumptions and limitations with regard to th mathematical modeling of girder bridges by these methods have been discussed. From the appli-cation point of view a typical 4—girder right bridge having a span of 19.4 m and carriage width of 7.5 m has been analyzed for two critical load positions of IC class—A loading. A comparative study of the results for r ir.det bending moments and deflections as obtained by the above mentioned methods has been carried out and certains conclusions arrived at.