DOHA: Qatar Railways Company (Qatar Rail), the company overseeing the construction of the integrated railway network, has taken delivery of the first of 21 tunnel boring machines (TBMs).
TBM S-865, also known as ‘Lebretha’ was manufactured by Germany’s Herrenknecht, and is the first of four TBMs which will be launched for the Doha Metro as part of the Red Line North Underground project — the design and build (D&B) joint venture that is being led by Italy’s Salini Impregilo, with South Korea’s S K Engineering and Construction Co Ltd, and Galfar Al Misnad Engineering & Contracting WLL (ISG JV).
For the Red Line North Underground project, a total of four TBMs (named Lebretha, Al Khor, Al Mayeda and Al Bidda) are proposed to bore the required rail tunnels.
TBM Lebretha will be assembled and launched from the Al Wahda site towards West Bay Central. At West Bay Central it will be disassembled and re-assembled at Al Wahda and then travel towards Doha Golf Course. It will bore the West Tunnel of the Drive while TBM Al Khor will bore the East Tunnel when it arrives.
TBM Lebretha will travel a distance of approx. 7.954 km and will take approx. 22 months to complete – between Q3 2014 to Q2 2016). The average speed will be between 14m/day to 21 m/day, depending on ground conditions. And its daily excavation quantity will be approx. 680m2, with a predicted total excavation quantity of 5,408,720m2.
Each of the TBMs for the Doha Metro measure 7.05m in diameter and 120m in length, therefore to ensure transportation was successfully managed, TBM Lebretha was dismantled into 22 sections which were easier to transport including the cutter head.
It commenced its journey, by sea, to Qatar and finally arrived over the weekend at the Doha Port. Some residents may have seen the sections of TBM Lebretha travelling along Al Corniche earlier this week making their way from the Doha Port to the first launch site of Al Wahda, next to the Qatar Exhibition Centre.
The scope of work for the ISG JV on the Red Line North project comprises the design and construction of approximately 13.4km twin-bored tunnel, including seven underground stations, between the proposed Msheireb Underground Station and Doha Golf Course via Doha West Bay. The tunnels will be built at an average depth of approximately 20 metres below ground.