Cracks have been detected in as many as 18 piers across three under-construction Metro corridors. While maintaining the cracks are minor in nature,DMRC has nonetheless asked civil engineering consultants Shirish Patel and Associates to re-check the design of these points.
On July 12,six people died at a Metro construction site in Zamrudpur in south Delhi in an accident allegedly involving a cracked pillar.
Delhi Metro engineers during their inspection have found hairline cracks on eight piers of the Central Secretariat Gurgaon corridor,two piers of the NOIDA corridor and eight piers of the Central Secretariat-Badarpur corridor, DMRC spokesperson Anuj Dayal said.
The expert team that was engaged after the Zamrudpur incident to conduct a structural audit of all cantilever piers of Phase II has now been directed to re-check the designs on these piers.
DMRC officials said the discovery of the cracks just a fortnight after the Zamrudpur mishap has caused concern. Dayal,however,said,The cracks appear to be minor but are being kept under observation by the Metro engineers. Surface cracks are not uncommon and Indian standard codes for design of reinforced concrete structures permits tension cracks within limits.
Sources in Gammon India Limited,the contractor for the Badarpur and NOIDA lines,said the cracks were old surface cracks.