Design of the Dubai Metro light rail viaducts—superstructure

Abstract

The Dubai Metro light rail scheme is a flagship project in the United Arab Emirates which is currently one of the largest civil engineering projects under construction and, when completed, will be the longest fully automated rail system in the world. The first section of the rail system is due to be opened in September 2009. This paper describes the scheme outline and contractual setup for the viaduct design and discusses the design and construction of the viaduct substructure. In particular, the design methodologies used for the piled foundations, single reinforced concrete columns and prestressed concrete pier heads are discussed as well as the design of elastomeric bearings that were used extensively for most of the viaduct spans. Seismic loading governed the design of many of the foundations and the seismic analysis and design methodology adopted is discussed, together with specific reinforcement detailing requirements. Railstructure interaction analysis and design is also covered. Other critical design issues resolved included the fatigue performance of cranked reinforcement and the treatment of the onerous construction loading from overhead gantries used to erect the precast deck segments. Bridge Engineering 162 Issue BE2 Design of the Dubai Metro light rail viaducts-substructure Smith N Hendy

Dubai Metro footbridge design

“…The piers generally comprised 1?75 m diameter columns founded on 2?2 m diameter monopiles, embedded into the ground between 10 m and 25 m. A typical standard pier is shown in Figure 5. Using the same design basis as used for the viaducts (Smith and Hendy, 2009), the pile vertical loading resistance was provided entirely by skin friction without any reliance on end bearing. The use of a monopile solution minimised the excavation requirements for the foundation construction and limited the duration of road closures or carriageway possessions in the urban environment.…”

“…The use of a monopile solution minimised the excavation requirements for the foundation construction and limited the duration of road closures or carriageway possessions in the urban environment. Design and detailing issues associated with monopile construction are discussed further by Smith and Hendy (2009).…”

“…Other critical issues that were resolved included the design of fillet-welded This paper describes the design and construction of the steel truss footbridges connecting the elevated stations to their entrances. Separate papers (Smith et al, 2009;Smith and Hendy, 2009) cover the design and construction of the viaduct superstructure and substructure.…”

Editorial – Bridge Engineering June 2009

“…Many have said that one sees further by 'standing on the shoulders of giants' (Newton to name one) and indeed this is the very essence of a learned society and the way we all move forward and develop (continuing professional development) I am sure none of our authors would pretend to be giants, but there are lessons here to be learnt.In their two papers on the design of the elevated Dubai Metro, 1,2 Smith, Hewson and Hendy give a useful description of the rail superstructure and its supports. Also, more than that, they present a discussion on the difficulties in realistic modelling of such a structure for the various design conditions.…”