Digging work on, diversions in place
LUCKNOW: Digging work on the underground stretch of metro rail has started in front of Bapu Bhavan. Work on 3.5-km-long route from Hussainganj to KD Singh ‘Babu’ stadium began with the foundation laying ceremony of a ‘guide wall’ on the first Monday of Sawan.
“The occasion is considered to be auspicious, so we started from that day,” said Kumar Keshav, MD, Lucknow Metro Rail Corporation. The work on the diaphragm wall will start on August 2 and is expected to be completed within 3 months, he said.
The tunnel boring machines (TBMs) would enter the pit in front of Bapu Bhawan to dig the mud out. A station box will be constructed to facilitate the entry of TBM into the pit. Kumar Keshav said the TBM is like a giant coffee can, but instead of a lid on top of the can, the TBM has a rotating cutter on its head with teeth that chew up the soil.
In addition to that there is a corkscrew-like device behind the rotating cutter that carries the soil backward through. The TBM will start working once the diaphragm wall is created. It will push forward, cut and remove the soil to erect tunnel lining.
There will be segment-wise removal of soil surrounded with a cement grout, leaving behind a circular tunnel shell, said Keshav. The concrete tunnel lining is a must so that it can support the surrounding ground.
The survey of structural strength of buildings on this 3.5-km route has been completed.
Mud removed from tunnel would be dumped at a chunk of land given by irrigation department near Shaheed Path.
To protect the environment and prevent particles of soil from spreading in the air, the LMRC will ensure that the mud is carried to the dumping site on trucks with torpelene covers. The tyres of these trucks would be washed before they hit the road after dumping the mud at the site.
“You cannot find mud particles on the road or in the air despite our trucks being in operation. Pollution levels will be monitored before the mud is removed. We will continue to watch pollution levels when the construction would be on,” added Keshav.