All photos courtesy of Qatar Rail

Qatar has acquired five of the 21 mammoth tunnel boring machines (TBMs) it needs to help dig the underground stations and railways for the Doha Metro.

Four of them arrived at the Doha Port this week: Al Mayeda, Al Khor, Lehwaila and Al Wakra, which were all manufactured by Germany-based Herrenknecht. They, along with Lebretha, which arrived in April, will be used to bore tunnels for the Red Line North and South underground projects.

Some 10 stations are expected to be completed for the Red Line North (which links Msheireb to the Doha Golf Course via West Bay) and eight stations for the Red Line South (which links Msheireb to Hamad International Airport) in the first phase of construction.

It and parts of the Gold and Green lines, which will use six TBMs each, are expected to open to passenger traffic in 2019.

In a statement, Qatar Rail said:

“Each TBM will travel a distance of between 7-9 km and will take approx. 2 years to complete their respective journeys. The TBM average speed will be between 12m/day to 21m/day, depending on ground conditions. Daily excavation quantity will be over 600m³, with an estimated predicted total excavation quantity of over 5,000,000m³.”

However, digging won’t begin just yet. The TBMs must be disassembled into smaller pieces at the Doha Port before being transferred to the construction sites, due to their large size. They will then be reassembled onsite, a process that takes up to a few months.

The TBMS will be used to cut circular holes in the ground some 20 meters beneath Doha for all the lines. Previously, Qatar Rail officials said all 21 machines would be working by 2015, adding that residents may feel “minor vibrations” during work.

However, in today’s statement, officials said the tunneling would be “practically unknown to the population above.”

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