Speed goes deeper
Delhi Metro’s Airport Express Line has reached new depths to facilitate the transport of Commonwealth Games’ visitors. Yogender Malik checks out if the line is on track for the July 2010 deadline.
T wo years back, a ride from Delhi’s international airport to the city centre used to take anywhere between one and a half hours to two hours, depending on what time of day one was commuting. Come July 2010, this distance could be traversed in less than twenty minutes.
With a view of better facilitation of commonwealth visitors’ transport from city’s airport to heart of Delhi and vice-versa, Delhi Metro Rail Corporation (DMRC) Ltd has embarked upon one of the most challenging projects of connecting the once commercial hub of Delhi to the Indira Gandhi International (IGI) airport.
It will be done through the Airport Express Link (AEL), a 22.7km long stretch on the Delhi metro. Around 16km of this new project is underground, while a distance of 7km etween Buddha Jayanti Park and Mahipalpur is elevated.
The entire stretch will have a total of six stations – New Delhi metro railway station, Shivaji Stadium, Dhaula Kuan, National Highway 8, IGI airport and Dwarka Sector-21. This link will be operational by July 2010, three months ahead of the Commonwealth Games 2010.
Modelled on the lines of London’s Heathrow Express, the new service will be the fastest ride from Connaught Place to the IGI airport in just 18 minutes. The trains will be different from the ones used at the existing Delhi Metro lines, with many added facilities.
Speaking to Construction Week (India), Anuj Dayal, chief spokesperson DMRC said: “DMRC is confident that the AEL from New Delhi to IGI Airport will be completed as per schedule, i.e., by August 2010. About 47% of the civil construction work has already been completed.”
This is for the first time that DMRC has used the concessionaire approach. Underground tunnel and the associated stations will be constructed by DMRC using the EPC contract route, while the laying of railway track and management of the railway service will be done by the Delhi Airport Metro Express Pvt Ltd (DAMEPL).
The DAMEPL is a special purpose vehicle (SPV) in which, Reliance Infrastructure has a 95% equity stake with Spanish firm CAF owning the rest. The facility will be transferred back to DMRC at the end of the 30-year concession period. CAF is Spain’s leading rolling stock manufacturer. The concession has awarded the contract to engineer and manage procurement, installation, testing and commissioning of all the electrical and mechanical systems to Hong Kong’s MRT Corporation Ltd.
Work, distributed in six packages, is in full swing with contractors like HCC Ltd, Senbo Engineering Ltd, IJM, L&T Ltd and Afcons Infrastructure Ltd on the job. Some contracts are being executed in consortium with foreign companies like Shanghai Urban Construction Group of China and Alpine Mayreder of Austria.
DMRC is taking general advisory services for this project from a joint venture comprising Pacific Consultants International of Japan, Japan Railway Technical Services, Tonichi Engineering Consultants of Japan, Rites Ltd and Parsons Brinckerhoff.
The deepest tunnel
Work on this 45m deep and 1,556m long tunnel which began at the New Delhi railway station metro site in October 2008 was completed in the last week of April this year.
It was indeed very challenging to construct this tunnel 20-25 m below the existing tunnel at Central Secretariat – Vishwavidyalaya line at Rajiv Chowk. “Construction was carried out in the sensitive Ridge area using New Austrian Tunnelling Method (NATM) so that the environment was not affected. Special technology is being used to build the viaduct over eight existing roads and a railway line at Dhaula Kuan with minimal disruption to traffic,” Dayal says.
Three underground contracts have been awarded to different companies. One for the 3.7 km of twin-tube bored tunnels from New Delhi Railway Station to Shivaji stadium and two underground stations was bagged by a joint venture (JV) of Alpine Mayreder of Austria, HCC Ltd and Samsung of Korea.
Under the second contract, Alpine Mayreder with HCC will design and construct the next 2.6 km of the line as a 10m diameter single-tube, double-track NATM tunnel. The third contract is for a total 2.5 km stretch of 1.7 km twin tube TBM bored tunnel and 800m of open cut work into the Airport. It has been awarded to the Shanghai Urban Construction Corp (China) in JV with Indian EPC major L&T Ltd.
It is for the first time in India that girders longer than the usual 2.5 to 3 metres have been utilised for this project. These girders are 25 metres long and weigh about 120 tonnes each.
Similar girders have been used earlier in China and Taipei. It is estimated that using the extra-long girders is saving up to Rs5 crore of construction cost. Reportedly, these type of girders were also to be used for the Mumbai Metro. However, the idea was dropped due to the logistical difficulties arising out of the narrow roadways in the city.
The Airport Express Line – Overview
Length: 22.7 km (7km elevated + 15.7 km underground)
No. of stations: Six
Lowest point on tunnel: 40m
Stretch where 40m depth maintained: 250m
Deadline: July 2010
Expected ridership: 42,500 by 2010; 86,000 by 2021
Construction cost: Rs4,000 crore approximately.
Business model: Public-private partnership (PPP)
Trains: CAF (It will provide 8 trains with six coaches each. Deliveries will start from January 2010. All the coaches are being manufactured in CAF’s factories in Spain.)
Signalling, power supply & baggage handling: Siemens, Germany & its Indian subsidiary Platform screens: Faiveley Transport (French Group)
Automatic fare collection machines: Spanish firm Indra Sistemas
Tunnel ventilation equipment: ETA
Lifts & Escalators: Kone and Schindler respectively