Thaindian News

New Delhi, March 15 (IANS) Even though the national capital lies in high-risk seismic zone IV, Delhi Metro riders need not panic as its infrastructure is earthquake resistant and can withstand quakes measuring up to 7.5 points on the Ritcher scale, an official said.

“The Metro stations, viaducts and underground tunnels have been designed in a manner that they can withstand earthquake forces likely to occur in zone IV of the seismic zones identified in India,” Delhi Metro Rail Corporation (DMRC) spokesperson Anuj Dayal said.

Zone IV is prone to earthquakes measuring 7 to 7.5 on the Richter scale. The Metro network has been designed to withstand earthquakes up to 7.5 magnitude.

“Delhi Metro’s design structures posed a number of challenges, especially in the underground sections, as there were no Indian codes available for designing underground civil structures to withstand earthquakes. The DMRC (Delhi Metro Rail Corporation) follows the British and European standard codes for elevated and underground structures,” Dayal said.

Besides, the DMRC has adopted additional measures to tackle any disaster in the underground section.

“An earthquake sensor has been installed at Patel Chowk underground Metro station to measure tremors. The sensor alarm is generated automatically whenever it measures vibrations equivalent to 7 points or more, which becomes an advance warning system for all Metro train operators,” he added.

To make the Metro structures quake proof, all the piers have a pile foundation going about 10 to 15 metres below ground level to make them strong. Further, bearings with rubber padding have been put to make the structure more pliable.

Seismic concrete retainers have also been incorporated in the design to prevent dislodgement during tectonic movements, the official said.