Rehabilitation of Bridge Superstructures via the Addition of Girder Lines. II: Practical Considerations

A companion paper reported on theoretical considerations associated with adding girder lines to rehabilitate highway bridge decks and superstructures. This article reports on practical, construction, and cost considerations associated with the addition of girder lines rehabilitation strategy. Results of the investigation indicate that adding longitudinal girders between the existing girders is a viable bridge superstructure rehabilitation strategy. The two primary merits of the strategy are (1) most of the work can be performed from the underside of the bridge, thus minimizing interference with traffic; and (2) the strategy strengthens and stiffens the deck/superstructure and, therefore, should significantly prolong the remaining service life of the existing girders and deck. The greatest drawback to the adding girder lines strategy is its high initial cost. Because of this high cost, the strategy is not recommended except in special cases.