PARTIAL INTERACTION ANALYSIS WITH SHEAR-LAG EFFECTS OF COMPOSITE BRIDGES: A FINITE ELEMENT IMPLEMENTATION FOR DESIGN APPLICATIONS

This paper presents a numerical model for the analysis of composite steel-concrete beams with partial interaction to account for the deformability of the shear connection. The proposed approach is capable of capturing the structural response produced by shear-lag effects and by the time-dependent behaviour of the concrete. The versatility of the FE formulation is demonstrated for a wide range of realistic bridge arrangements, e.g. from twin-deck girders to cable-stayed bridges. The accuracy of the approach is validated against the results obtained from more refined models generated with shell elements using commercial finite element software. For each bridge typology considered, both deformations and stresses are calculated to provide greater insight into the structural performance. Particular attention is placed on the determination of the effective width to be used for design purposes and on the stress distribution induced in the concrete component, together with their variation with time due to creep and shrinkage.