Chennai Metro Rail Limited has begun Phase II of its metro expansion, adding 116.1 km across three new corridors. This phase includes 43 underground and 76 elevated stations, enhancing connectivity from north to south and east to west in Chennai. The tunnel drive between Ayanavaram and Otteri marked the sixth TBM breakthrough, overcoming significant engineering challenges.
More Details:
Chennai Metro Rail Limited has commenced the expansion of the Chennai city’s metro rail network as part of Phase II after the successful completion of the Phase I and Phase I Extension. CMRL has ventured into an extensive infrastructure development in the city comprising three more corridors of metro rail for a total length of 116.1 km.
Background of Tunnel Breakthrough:
- The tunnel construction for the first 9 km underground section of Corridor 3 from Madhavaram Milk Colony to Kellys is being executed through M/s Tata Projects Limited and mobilised 7 TBMs for the tunnelling works.
- The TBM Kolli (S 81) tunnel drive started on 11.07.2023 from AyanavaramStation to Otteri station (Up line), covered a bored tunnel length of 903 m and break-through was done at Otteri shaft on 29.08.2024.
- This is the 6th TBM breakthrough carried out by M/s Tata Projects Limited under TU-01 contract. As a whole, CMRL has completed 7 TBM breakthroughs in phase-2 projects.
Challenges:
- The tunnel section between Ayanavaram and Otteri is the most complex tunnel section under the contract TU-01 with major challenges, such as the TBM S 81 (Kolli) first 500m tunnel drive negotiated with sharp 220 m radius curve and the last 200m tunnel drive with 280 m radius curves.
- Also, this tunnel drive completed with major challenges such as passing through densely populated areas and addressing more than 100 No. of bore wells along the alignment by providing alternate sources without any issue to the public.
- The complete tunnel drive was well managed within the allowable minimum settlements and extensive instrumentation and monitoring was ensured throughout the drive.
Brief about Phase-2 Expansion:
Corridor 3 comprising a total alignment length of 45.4 km from MadhavaramMilk colony to Siruseri Sipcot will be spanning across the north to south direction of the Chennai city and has a total of 28 underground stations and 19 elevated stations.
Corridor 4 is an east-west alignment for a length of 26.1 km connecting the beach front from Light House station to the Depot at Poonamallee has 9 underground stations and 18 elevated stations.
Corridor 5 also begins at Madhavaram Milk colony and connects through Koyambedu, Porur, Alandur and other residential/commercial development of the city to Shollinganallur for a total length of 44.6 km with 6 underground stations and 39 elevated stations.
Conclusion:
The expansion of Chennai’s metro network marks a significant milestone in urban infrastructure development, providing extensive connectivity and easing commutes across the city. By navigating complex tunnelling challenges and ensuring minimal disruption to the public, Chennai Metro Rail Limited showcases its commitment to efficient and sustainable urban transit solutions.
Source: CMRL – Press Release | Images Credit: CMRL
