: Delhi Metro Rail Corporation has completed launching 102 pre-cast U-girders in the Aluva-Palarivattom stretch so far, covering a total distance of 1.25 km on the metro viaduct.
An average of two girders and two pier caps are being launched in the stretch every night. Four girders were launched on Wednesday, defying the rain. “Going by the present pace, we hope to complete girder launch in the stretch by June 2015, as scheduled,” sources in the agency said.
Girder launch is nearing completion in the TVS Junction-Cusat and Aluva-Companypady stretch and at Kalamassery. Two 400-tonne-capacity cranes are used to launch each girder which weighs an average of 150 tonnes.
Another 100 girders are ready for launch and have been stacked at HMT yard in Kalamassery. Already, 166 pre-cast pier caps have been launched in the stretch, while 41 are ready for launch.
Girders are placed at a distance of 13.5 metres for metro stations, while it is 20m and 25m (where roads are wider) in the case of viaduct. All girders have provision for laying and utilities like power cable.
“Except for scheduled launch of girders over North bridge, launching of girders in the city (Palarivattom-Maharajas College Ground stretch) has been held up because of inordinate delay in shifting pipelines and cables. Delay in widening narrow corridors too has hampered girder launch. As of now, 115 girders have been readied for launch and the rest will be cast by January 2015,” sources said.
Uncertainty plagues girder launch in the Maharajas Ground-Pettah stretch due to State Government’s delay in acquiring land to widen the road for commencing metro’s civil works. In the meantime, DMRC will commence launching girders for metro viaduct over Ernakulam North over bridge from Saturday night.
“We hope to complete launching all 52 ‘I-girders’ over the bridge by November first week as scheduled, at the average rate of two girders per day,” said sources associated with the works. Forty pre-stressed concrete girders are already stacked at Manappattiparambu Ground for the launch. They are transported to the bridge using hydraulic axle trailers and launched using cranes.
Each girder weighs 75 tonnes, is 25 metres long and is 1-metre wide. “Unlike launching girders in metro viaduct elsewhere where there is sufficient width, there are constraints like steep gradient of a four-lane bridge,” they said. Traffic through the bridge will be diverted in between 10 pm and 5.30 am starting Saturday night, following which motorists will have to use A.L. Jacob or Pullepady overbridges to commute to the city and back.
