The Metro 3 project for Colaba-Bandra-Seepz will now be undertaking the most challenging work of underground tunneling at the Mithi River near the Bandra-Kurla Complex. Mithi river belt comes between the Dharavi and BKC station of underground Metro 3. This work is expected to be completed in three months from March 2019 to May 2019. Earlier, such tunneling work was done for underground Metro of Chennai.
This will be done by using the tunnel boring machine, which will be 18 to 19.5 meters deep from the Mithi river belt. PDM Rubber Mushroom Gaskets will be used for the Holo Casting Ring used during the work of Tunnel Boring Machine. These Gaskets gives complete protection from water leakage. So there will be no risk of water to come into the tunnel.
Special care will be taken during operation of tunnel boring at MithiRiver. This tunneling will be done by ‘Earth Pressure Balance’ technique. Looking at the water of the MithiRiver, special care is being taken for the tunneling and the overhead pumps will be used to pull water from the tunnel. This water will be used to clean the wheels of tunnel boring machine. Geothermal investigations will be carried out before the tunneling work.
3D Reflexometer
The 3D Reflexometer will be used for full tunnel monitoring, it is mostly used at every 100 meters in tunneling but for the MithiRiver tunneling it will be used at every 50 meters. Therefore, it will be possible to keep a close watch on all geographical movements in tunneling work.
Crossover in MithiRiver
Using the New Austrian Tunneling Method (NATM), a crossover will be created between the up and down routes of the metro. The purpose of creating a crossover is to get the space to change the track to the metro train. NATM technology is done by manual digging. Since this land is of asoft soil, it is said that there will be no need to have a controlled blast for crossover.
Integration at BKC
BandraKurla Complex will be the junction for the integrationof both Metro 3 and Metro 2 line. It will help in integration of both subway and elevated Metro. BKC will be the longest Metro station of 475 meter. There will be 6 entries and exit points for the BKC station.
AshwiniBhide, Managing Director, Metro Rail Corporation
The work of 15 tunnels for the Mumbai Metro is underway and the administration is taking complete safety for it. The most up-to-date technology of Tunnel Boring Machines is being used for Mumbai Metro and it will also be used for Mithiriver too.
