From Gulf News
"Machine bores through as Metro tunnel work starts
Dubai: Al Bugeisha, the Tunnel Boring Machine (TBM) for the Dubai Metro, has begun tunnelling work for the underground rail tracks, said a senior official.
The TBM has been named Al Bugeisha after the small desert rodent found in Asia and North Africa and is known by that name in the UAE for its characteristics of burrowing.
Breakthrough
"The success of the TBM in breaking through the wall is a significant achievement and is a major part of construction for the underground part of the Dubai Metro project," said Adnan Al Hammadi, Director of Construction at Dubai Metro.
He said it is one of the most critical stages during construction of the tunnel. The tailor-made TBM has been assembled in Japan especially for Dubai's Metro.
"The machine has been manufactured to bore through hard rocks or sand layers and almost anything in between," said Al Hammadi.
"Al Bugeisha has successfully broken through the tunnel for the underground part of the Red Line for the Metro from Union Square in Deira towards Burjuman Centre - the two major underground stations where the Red and Green Lines will cross each other," said Al Hammadi.
The machine will also pass under the Dubai Creek for tunnelling work. The Roads and Transport Authority (RTA) has already completed the survey and determined the route of the work. "The tunnel will pass under the creek up to a length of 1.6 km and at a maximum depth of 30 metres. He said the residents will not feel any impact of tunnelling work because there will hardly be any vibration," he added.
Minimum disturbance
Al Bugeisha has a diameter of 9.56 metres, is 82 metres long and weighs 1,000 tonnes.
TBM's are used as an alternative to drilling and blasting methods and have the advantage of minimum disturbance to the soil by producing a smooth tunnel wall. "This significantly reduces the cost of lining the tunnel," Al Hammadi said.
The second TBM shaft at Union Square is also complete. It will be used to tunnel from Union Square to Al Rigga and from there to City Centre.
The Dh15.5 billion Dubai Metro project has a Red and Green line with a total length of 69.7km. There will be a total of 12.3km of underground metro line."