EVALUATION OF BENDING MOMENT DUE TO GEOMETRICAL NONLINEARITY IN MAIN GIRDER OF CABLE-STAYED BRIDGES

Bending moment due to geometrical nonlinearity in a main girder should be checked on designing cable-stayed girder bridges. Even though the employment of nonlinear analysis by an electronic computer is powerful, much time is also inevitable for carrying it out.In this paper, a formula to estimate the bending moment due to nonlinearity is proposed and also dominant parameters which have a close relation to nonlinear behavior of the girder are summarized. This simple formula is useful for designers' judgement whether nonlinear effect should be taken into account or not beforehand. In addition, it is available for selecting a bending rigidity of the girder of long-spanned cable-stayed girder bridges at preliminary design stage.