Widening of an Existing Bridge to Accommodate Two Traffic Lanes - Al Bustan South Project in Qatar

Abstract

Driven by Qatar National Vision 2030 and catering to the 2022 FIFA World Cup, Qatar is undertaking an extraordinary and ambitious programme of infrastructure development to deliver a world-class new and upgraded road infrastructure network. Projects designed to improve highway capacity, connectivity, and safety through the urban and rural parts of Qatar and to meet current and future demands of population and economic growth. In this paper, the authors discuss some of the most critical and challenging considerations in putting a planning and design process on a path to deliver successfully a bridge deck-widening project, implementing a collaborative approach. The case study of upgrading an existing ramp bridge will be presented, where the one lane deck was converted to two lanes to accommodate the heavy traffic flow. The fast-track construction schedule necessitated the widening from one side by 1.15m, while the extended slab was supported on a steel strut connected monolithically on the concrete box girder web (bottom) and extended part (top) through shear dowels. To meet the tight construction schedule and the local market material constraints, built-up sections were utilized with variable configurations along the length of the bridge. Further, several epoxy resin products were studied and utilized for the drilled bars on the extension part and the drilled dowels of the web. The replacement of the existing bearings was necessitated due to the additional weight of the extension.