NEW DELHI: The horror of the Zamrudpur Metro collapse came alive again on Saturday when fresh cracks were noticed on two piers with cantilevers

on the under-construction Noida line.

Trial runs on this Metro line, slated to open to the public by August-end, started only on Saturday. The piers were inspected by Delhi Metro Rail Corporation managing director E Sreedharan, who has ordered a detailed inspection of one of the cracks. The other, he observed, is superficial.

The pier which collapsed leading to the Zamrudpur tragedy also had a cantilever, which is a horizontal projection jutting out of the pillar.

Cantilever piers are used at curves on the Metro line. Both the Badarpur line, where the mishap took place, and the Noida stretch have the same contractor, Gammon India.

The matter came to light when the consultant — M/s Shirish Patel and Associates — appointed to check other Metro structures, especially cantilevers, on all the under construction Phase II lines noticed the cracks and informed DMRC of this. The consultant was appointed soon after the Zamrudpur incident.

The cracks were spotted on Piers 10 and 14 located near the Indian Oil building near Sector 14, Noida. After a thorough inspection, it was concluded that the crack on Pier 14 was superficial and not a matter of concern. But a further investigation was ordered into the one on Pier 10.

DMRC managing director E Sreedharan, who inspected the piers, said: "Both the hairline cracks seem to be superficial and related to masonry, which doesn't have a bearing on the strength of the piers. But we are not willing to take any chances now. This is why a more detailed investigation has been ordered into one of the cracks."

Sreedharan climbed the piers personally to check the cracks. The one on Pier 10 has reportedly been supported with metal struts and will be put through specialized ultrasonic testing. The trial runs on the 13.1-km long Noida line have only been started on the Yamuna Bank-New Ashok Nagar stretch for now and are expected to be extended to Noida City Centre Sector 32 after 10 days.

But with one of the cracks being examined now, this could be delayed. A DMRC spokesperson, however, said neither of the cracks appear to be serious and trial runs on the stretch would progress as per schedule. In contrast to the Zamrudpur piers, the cantilevers on the Noida line are smaller — 2 metres as compared to 4 metres.

The cracks are being taken seriously as the concrete girder which collapsed in Zamrudpur was resting on a pier on which cracks were noticed before the mishap.

Even as Sreedharan later clarified that the collapse was not caused by the crack on Pier 67, the reason for the mishap is still not known. The report of a four-member committee investigating the incident has been submitted to DMRC, but has not been made public yet.