Dubai Metro coming along

As the elevated section of the Dubai Metro is making rapid progress, the construction methods used are becoming more diverse. The first three spans of viaduct have been constructed using the Balanced Cantilever Method. The length of the longest span is 72 metres.

Engineer Adnan Al Hammadi, Director of Rail Construction Department in Roads and Transport Authority, said," The most significant consideration for the design of the Metro viaducts is the adaptability of the method of construction to suit the site conditions and constraints. The method of construction must be established before proceeding with the design."

"Unlike other viaducts spans that are relative short measuring less than 44 meters in length which have been constructed using Launching Gantries, these spans had to be constructed using the Balanced Cantilever Method as the total length of the spans is about 72 metres. In total there will be 17 spans constructed using this method along the Red Line of the Dubai Metro Project", he added.

Engineer Al Hammadi stated, "To facilitate the cantilever construction, a pier cap shell unit (a hammer-head shape) has to be installed then filled with reinforced concrete, the first viaduct segments on the piers are then installed (pier deck segment). "

"The adjacent segments (deck segments) are then installed on either side of the piers and secured simultaneously."

"Erection of the remaining deck segments proceeds two segments at a time one either side of each pier to ensure that the balance is maintained throughout the operation."