Structural analysis of concrete bridge decks: comparison between the Portuguese code (RSA) and the Eurocode road load models - Evaluation of the global and local effects

João Nuno Taborda Brás

Key information

Authors:

João Nuno Taborda Brás (João Nuno Taborda Brás Robalo)

Supervisors:

Ricardo José De Figueiredo Mendes Vieira (Ricardo José De Figueiredo Mendes Vieira); Francisco Batista Esteves Virtuoso (Francisco Batista Esteves Virtuoso)

Published in

07/04/2013

Abstract

The current national code (RSA) will be replaced by the Euro Norm EN1991-1-2, which represents in general an increase of the design loads of bridges. The evaluation of the differences between the effects caused by both load codes in two-beam bridge decks was made in a local and global context. For the local effects two semi-analytical methods were developed and calibrated using finite-element models, in order to evaluate the distributions of transverse moments in the deck slab (over the beams) due to wheel and knife-edge loads acting both on the overhangs and on the internal panel. The transverse moments evaluated at the mid-span of the internal slab due to both load codes by using an analytical solution were also compared. The longitudinal analysis was performed for bridge models with a different number of spans, deck widths and span lengths, in order to encompass in the analysis a wide range of practical cases; the maximum sagging and hogging bending moments and shear force were obtained by using the respective influence lines. Several graphs were created by using the results of all these analyses, local and global, in order to provide an efficient and expeditious form of comparison between the effects caused by applying both codes in a wide range of bridges. To evaluate the applicability of those graphs, two real bridges were analyzed by using the semi-analytical methods and the results were then compared with the values extrapolated from the graphs.