New Delhi, July 13 (IANS) A day after an under construction elevated section of the Delhi Metro collapsed killing six people, a crash during relief operations injured six people Monday. The cause for the crash was a mechanical snag in one of the four cranes supporting the heavy girder segment in place, officials said.
The metro relief efforts turned to tragedy as cranes and a metal girder crashed on to the ground damaging a few shops selling garden accessories.

One crane turned turtle when the arms of the other three supporting the load snapped in series. Six relief workers sustained minor injuries as a result, Delhi Metro Rail Corporation (DMRC) spokesperson Anuj Dayal told reporters at its headquarters at Barakhamba road.

Terming the relief operations as a “difficult, tricky and dangerous” process, he assured that it would all be over in a week’s time.

On Sunday, an elevated section of the Metro in Zamrudpur area collapsed, killing six people and injuring 15 workers. It was the worst accident in the history of Delhi Metro.

Around 200 Delhi Metro workers and engineers were gathered at the site in efforts to remove tonnes of debris and diverting traffic in Zamrudpur area of south Delhi when the second incident occurred.

“Four massive cranes were employed in relief and rescue operations since Sunday, one of which was a heavy capacity crane of 400 tonnes. This developed a snag in its arm or boom which was the cause for the crash,” Dayal informed.

Dayal explained that owing to the mechanical failure, the crane’s boom snapped and the weight of the mutilated 31 metre launching girder - which was hinged to one of the pillars since Sunday’s collapse - was transferred to the remaining cranes — two of 250 tonne capacity and another of 350 tonnes.

“The weight got transferred to the remaining three cranes which were working and had to take the extra load, as a result of which two of the other booms also snapped. Since they were supposed to work in tandem, one mechanical failure… all weight came on others and the third crane toppled over,” Dayal said.

The crane toppled over with its 16 wheels in the air and the launching girder crashed to the ground creating “slight panic and stampede”. Six people fell down and sustained “minor scratches”, Dayal said.

The three crane operators involved in the incident were unharmed and repair of the damaged shops will be done by DMRC, he added.

The site clearing operations to remove the collapsed concrete girder as well as the 31-metre-long metal launching girder began Sunday afternoon. The weight of the portion of the launching girder that was being lifted by the four cranes was about 200 tonnes.

“80 percent of the launching girder has already come onto the ground and will be cut using gas cutter machines and transported from the site, while 20 percent is still on the elevated concrete beam and is being lowered,” he said.

Dayal said that other damaged cranes were being removed with new cranes that were brought in to remove the debris.

“Although DMRC engineers and technicians are still working out how to dismantle the girder on the elevated section. One lane on the road should be opened by Tuesday afternoon for traffic and the other should open in six to seven days, by which time all operations would be complete,” Dayal assured.