By IANS,
New Delhi : Delhi Metro Rail Corporation (DMRC) Tuesday found a private construction company guilty for the collapse of an under-construction bridge that killed two people and injured 12 last month but decided not to punish it.
“The collapse of the flyover is a very sad incident and the contractor was guilty of the technical failure. The accident happened due to the slackness of the company,” DMRC chief E. Sreedharan said.
“The private company ‘AFCONS’ has a very good record and I know them for last 20 years. We are sending a show-cause notice to them but will not stop them from carrying out the unfinished projects,” he told reporters.
The show-cause notice will ask the firm why it should not be black-listed for a short period.
He said AFCONS was currently carrying out three DMRC projects including the affected Metro line in Laxmi Nagar in east Delhi.
Sreedharan said terminating the contract will only delay the work and will need a whole new process.
“We are not terminating the contracts but are placing foolproof mechanisms for avoiding such incidents.”
“Oct 19 is the blackest day in Delhi Metro’s 11-year-old history,” he said referring to the tragedy that happened early that Sunday morning.
Metro authorities said had the tragedy happened on a weekday, the loss would have been much more.
Sreedharan said a three-member technical committee set up to find the cause of the tragedy submitted its report Tuesday and it will be forwarded to the central and Delhi governments.
The committee conducted detailed investigations into the incident, including review of design, analysis of test reports of various elements, interview of witnesses and site visits.
The accident occurred a little after 7 a.m. Oct 19 when the launching girder was lifting pre-cast heavy cement concrete segments on Vikas Marg in Laxminagar. The collapse of the girder resulted in the death of a construction worker and a Blueline bus driver.
The committee found that the design of the launching girder was checked by a technical team.
During the segment lifting stage, the launching girder is supported on four support steel columns.
“The committee has come to the conclusion that the accident was due to the left side front tubular column failing,” Sreedharan said.
The tubular column consists of two tubes with telescoping arrangement. This was for obtaining the correct height of the supporting column. There are holes provided in the outer tube and inner tube and these two tubes are locked in position by inserting 100 mm steel pins through pre-drilled holes.
To carry the desired weight on the supporting column, a minimum of 10 pins are required to be inserted. But the evidence at the site showed that only four pins were inserted.
It was also found that the holes of the outer tube, which should match precisely with the holes of the inner tube for inserting pins, were enlarged by gas cutting – thus each pin took differential loads.
“The accident was, therefore, due to the omission and carelessness on the part of the contractor’s workers in failing to insert a minimum of 10 pins for each column and making the pins ineffective by enlarging the matching holes of the outer tube,” Sreedharan added.