Three viaduct spans constructed for Dubai Metro project

Each of these spans is being made up with a minimum of eight precast viaduct deck segments which are manufactured and transported from Jebel Ali casting yard.

Each segment being 10 meters wide and 4 meters in length is being assembled with other similar sized segments individually to form a complete viaduct span bridging across two supporting piers. Different spans together when assembled will form the bridge deck upon which the trains will travel. The lengths of the spans vary from 24-72 meters where the minimum number of segments per span is 8 and the maximum is 18 installed by launching girder number LG7, which is the first amongst seven other gantries to be used to construct the many viaduct spans along the Red Line.

The segments are match-casted and glued together. Post-tensioning then takes place using high strength cables threaded through the segments.

The launching gantries are equipped with their own lifting winch, power and control equipment to enable lifting and moving the heavy concrete segments accurately into position. There will be 11400 pre-cast concrete viaduct deck segments used for the Red Line, each weighing in excess of 50 tones.

The launching gantries provide a fast-track installation process which enables the installation of a complete viaduct span of 36m length in roughly two days. Concrete segments will be transported, on demand, from Jebel Ali Casting Yard to the launching gantries sites using heavy-duty Lorries.

The concrete segment installation process is a construction method used widely around the globe. It will be performed in accordance with internationally recognized standards and in compliance with pre-planned and approved detailed work methodologies.