Friday, June 25, 2010

Delhi Metro Making Arrangement for Extra rush

A new underground station has been added to existing Central Sec station to accommodate two new sections

With two new lines Gurgaon and Badarpur expected to be connected to the Central Secretariat station (CTST) soon, the Delhi Metro Rail Corporation (DMRC) is making final arrangements to handle the extra rush of passengers and trains at the station.

In an architectural feat involving capacity expansion, DMRC has constructed a new underground station parallel to the existing CTST and connected it to the original station. With this, it has become the only Metro system in the world to operate two different gauges broad (CTST-Jehangirpuri) and standard (CTST-Badarpur) from a common platform. While the Gurgaon-Qutub line will be linked to the existing Central Secretariat-Jehangirpuri line, the Badapur Metro will in September roll into the newly-built premises with standard gauge tracks.

Integration means that passengers won’t face hurdles in changing trains that will branch out to three different parts of the city. ‘‘Passengers entering this underground Metro station will find a common concourse where they can purchase tokens/smart cards. We have a separate ticketing counter at the new station. People can change between the lines at the concourse and platform level. We have also constructed a subway between the two stations,’’ said Anuj Dayal, spokesperson, DMRC.

But the integration was not an easy process. The biggest challenge was to make passages in the main load-bearing wall dividing the two stations. ‘‘The load on this wall was close to 10,5000 kg per running meter, as the road above the station sees constant traffic movement. Before making the passages, we had to provide adequate support to prevent the structure from collapsing or shaking when the trains cross the station,’’ said Kumar Keshav, director project and planning, DMRC.

For this, DMRC erected iron columns from the under craft to concourse level before cutting the wall. A total of six passages have been made four on concourse and two on the platform. ‘‘We started planting the columns from the foundation level. As our line 2 (CTST-Jehangirpuri) was operational, we had to ensure that the walls didn’t shake due to vibrations caused by train movement,’’ said Keshav.

Due to heavy movement of vehicles on the road above the station, DMRC engineers had to constantly monitor the load on the columns. Special load cell monitors were used thrice a day to monitor the load on the columns. Once the columns were in place, DMRC started cutting the wall at the earmarked points to create the passage. ‘‘Our cranes can’t take more than 6000 kg load, so we decided to take out blocks weighing 4000 kg each. To make one passage, the wall was cut in 105 blocks. We then reconstructed the pillars to support the main wall,’’ said Keshav.
Another big challenge was to ensure smooth operation on CTST-Jehangirpuri line, which is one of the busiest sections with close to 552 train trips every day. ‘‘We couldn’t shut down operations on line 2 to interconnect the two stations,’’ said Keshav.


Two new lines from Badarpur and Gurgaon will soon be linked to the existing Central Secretariat station (CTST)

To handle the extra rush of passengers and trains, DMRC has constructed an additional underground station at CTST which will be connected to the existing station at concourse and platform

This is the first time two different gauges standard and broad will operate from the same station

Jehangirpuri-CTST (broad gauge) is functional and will be connected to the newly-opened Qutub-Gurgaon corridor in August

CTST-Badarpur (standard gauge) is scheduled to open in September

THE INTEGRATION PROCESS Six passages four on concourse and two on platform are made to connect the two stations 52 iron columns used on each level to support the wall where the passages are made

Columns used at three different levels from foundation to the concourse. Total height of each column is 18 meters Each passage is 7.6-metre wide 35 meters of main wall was cut to make the passages
Cost | Rs 275 crore (approx)
Number of workers | 700 15
contractors simultaneously working on the project

CTST will act as a point for passenger interchange once the CTST-Badarpur line is made operational