Model Studies of Skew Multicell Girder Bridges

A model study of a series of simply supported skew box girder bridges is presented. The prototype bridge was a four-cell reinforced concrete design, 33 ft, 10 in. (10.31 m) wide, and 4 ft, 10 in. (1.47 m) deep. A 1/29-scale model was made in aluminum to study the response of such a design when made from linearly elastic material. The span of the model was successively reduced from 69.5 in (1.76 m) to 22.5 (0.57 m) to study the effect of variation in span. The effect of skew angle was studied at angles of 0°, 30°, and 45°. The following were measured: boundary reactions, strains on a right transverse section close to midspan, and deflections at selected points. The data were reduced by computer, and distribution graphs of longitudinal stress and transverse bending moment were plotted by Calcomp Plotter. Based on these data, certain general observations are made regarding the behavior of skew box girder bridges.