Delhi Metro building an all-steel station at Chhattarpur
The Chhattarpur station on Delhi Metro's Central Secretariat (CTST)-Huda City Centre (Gurgaon) corridor will be a unique structure - it will be made entirely of steel unlike all the other stations on the netowrk which are made using concrete and some steel elements.
Delhi Metro Rail Corporation (DMRC) spokesman Anuj Dayal said this unconventional construction technique was being resorted to so that the CTST-Gurgaon corridor was opened to the public on time before the Commonwealth Games, which the capital will host in October this year.
According to him, the the conventional method of construction using concrete would have taken at least two years, which owuld have delayed the line substantially.
He explained that the DMRC, which was trying to acquire the piece of land for the station since September 2006, was able to get the two-hectare plot only in October 2009 after prolonged litigation.
The DMRC engineers, therefore, decided to adopt a special design using special structural steel to construct the Chhattarpur station in a record time of only eight months. No metro station in India has been built in such a short span of time so far in India, Mr Dayal said.
The station is now being built with pre-fabricated steel structures by Jindal Mectec, who are making the station using high strength steel (IS 2062 Grade B).
According to him, since the time available was short, the steel columns and other structures were pre-fabricated at a workshop in Gurgaon and brought to Chhattarpur by trailers, where they are being erected using cranes with long booms for easy maneuverability and movement at the site.
About 70 per cent of the work for the station has already been completed and four cranes of 20 tonnes capacity each are currently operating at the site where lifting, holding and bolting activity of the steel structure is taking place. The quality of the construction is being checked through radiography of the joints (X-ray) and DPT (Dye-Penetration Tests).
To ensure good quality control, the DMRC did not permit any welding activity at Chhattarpur and only the steel structures had to be joined together by using bolting arrangements.
After the erection of the steel structures, 180 mm of concerete will be laid on top of the structure. The above procedure, however, is more expensive and will cost DMRC an additional 30 to 50 per cent, Mr Dayal said.
By adopting this technique, the DMRC will able to open Chhattarpur for through running of trains on the Central Secretariat -Gurgaon line by June this year, by when it hopes to complete the operational requirements of track work, platform work, roof work (OHE, signalling and so on) by this time. However, the rest of the station building will take more time for construction and this station will be opened by August 2010 when the entries, exits and finishing will be done.
DMRC expects that about 12,000 passengers will use the station every day by 2011.