QATAR Railways Company (Qatar Rail), the company overseeing the construction of the Qatar's integrated railway network, announced the successful breakthrough of one of its Doha Metro tunnel boring machines (TBM) at Msheireb station. The breakthrough is the first at this main metro station marking the progress of the underground tunneling works. The TBM named Al Mayeda, belonging to the Doha Metro Red Line, was launched at Al Corniche station in November 2014 and achieved breakthrough at Msheireb, having dug 1.6km of tunnel. Having completed its first job, it will now be transported to Al Qassar station where it will start work again. The breakthrough of Al Mayeda was subject to a few days delay at the end of its journey. Shortly before breakthrough the machine unexpectedly encountered a water source which had to be dealt with properly and safely prior to its appearance into the open air at Msheireb. Al Mayeda is one of 21 TBMs assigned for the Doha Metro project. All Qatar Rail TBMs are currently operational, and are on track to complete the tunneling phase by 2017. 30km of tunnel have now been completed out of a total of 113km. When Qatar Rail last reported progress in April, the figure was 18.5 km. Msheireb station, the flagship station which will be the central hub of Doha's public transportation system, will be the major interchange for, Red Line, Green Line, and Gold Line. Excavation at Msheireb is approximately 40m below ground. Construction works there are scheduled for completion by 2018. Msheireb station is currently seeing important milestones in the delivery of its foundation works. According to Qatar Rail engineers, the station's excavation is equivalent to the length of Burj Qatar, and the land area is equivalent to five football pitches. As for the weight of the excavated soil, it counts as much as 500,000 Toyota Land Cruisers. Commenting on the tunneling progress, Eng. Hamad Ibrahim Al Bishri, DCEO of Qatar Rail, said: "During the past year, we have achieved significant developments on the Doha Metro project thanks to the joint efforts of the company and its contractors. While the excavation phase is making good progress at all stations under the supervision of our skilled team, we are happy to celebrate a new successful breakthrough here at Msheireb.” He added: “Mining through different ground layers that vary constantly under highways and road facilities with a large-diameter TBM is a feat in itself. The short delay at the end shows how unpredictable our work can be sometimes and how important is the skill of our engineers and quality of planning. It is not always possible to know when these incidents might happen, but it is certain that they will occur at some point and we plan on this basis.” So far, Qatar Rail has had over 70,000 lorry movements for excavation at Msheireb Station. — SG
