Qatar Railways Company (Qatar Rail), the company overseeing the construction of the integrated railways network, has received four more tunnel boring machines for the first phase work of the Doha Metro.

All the four machines were manufactured by Germany’s Herrenknecht and will be used for the Red Line North and South underground projects, said a statement from Qatar Rail.

The company has ordered  21 such machines, which will dig through a distance of 8 km in 22 months, it added.

Out of the new deliveries, two will be used for the Red Line North underground project, whose design and build will be undertaken by a joint venture led by Italy's Salini Impregilo and comprising South Korea’s SK Engineering & Construction and Qatar’s Galfar Al Misnad Engineering & Contracting.

The other two will be launched into service for the Red Line South underground project, whose design and build will be undertaken by a JV led by the French-Qatari company QDVC and comprising South Korea’s GS Engineering and Construction and Qatar’s Al Darwish Engineering.

Each machine will travel a distance of between 7-9 km and will take two years to complete its journey. The TBM average speed will be between 12m/day to 21m/day, depending on ground conditions. Daily excavation quantity will be over 600 cu m, with an estimated predicted total excavation quantity of over 5 million cu m.

Qatar Rail said the tunnel boring machines were ideal for Doha as they hardly affect the vibrant and active city life. Needing only one point of entry, they can tunnel below the city streets, practically unknown to the population above.

They are also ideal for longer lengths of uninterrupted tunnelling, as is required for the Doha Metro project, the company stated.

The scope of work for Red Line North Underground comprises the design and construction of 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 20 meters below ground.

Red Line South underground extends from Msheireb in the North to Hamad International Airport in the South. The scope of work includes seven underground stations and the design and construction of 14km twin-bored tunnel to be built at an average depth of 25 meters below ground.

Qatar Rail said it will receive 16 more tunnel boring machines over the coming months, for utilisation between the Red Line North, Red Line South, Green Line and Gold Line underground projects.

The Green Line – a JV led by Austria’s PORR Bau and comprising Saudi Bin Laden Group and Qatar’s Hamad bin Khaled Contracting will receive six machines, while the Gold Line – recently awarded to a joint venture led by Greece’s Aktor and comprising India’s L&T, Turkey’s Yapi Merkezi and Sezai Turkes Feyzi and Qatar’s Al Jaber Engineering – will also receive six.-TradeArabia News Service