Mumbai, June 7: The Mumbai Railway Vikas Corporation (MRVC) proudly announces the successful breakthrough of Tunnel-2 (Wavarle Tunnel), the longest tunnel in the Mumbai Suburban Railway Network, as part of the Panvel-Karjat railway project under the Mumbai Urban Transport Project 3 (MUTP-3).
Project Overview
The Panvel-Karjat railway project encompasses the construction of three tunnels, totalling 3164 meters in length:
Tunnel-1 (Nadhal Tunnel): 219 meters
Tunnel-2 (Wavarle Tunnel): 2625 meters
Tunnel-3 (Kirawali Tunnel): 320 meters
Milestone Achievement
The underground excavation of the Wavarle Tunnel commenced on February 22, 2023. Today, on June 7, 2024, the breakthrough was achieved in the presence of MRVC's Chairman and Managing Director Shri. Subhash Chand Gupta, Director (Projects) Shri. R.K. Srivastava, ED (Tech) Shri. Vilas Wadekar, CVO Shri. B.K. Gangte, GM (Civil) Shri. Vinod Bhangale, and other key personnel involved in the project's construction. This significant achievement marks a major step forward in the project's execution despite logistical challenges and complex geological conditions.
Construction Methodology
The Wavarle Tunnel's construction adhered to the New Austrian Tunnelling Method (NATM), which involves a cyclic sequence of excavation followed by the installation of a primary support and a delayed secondary lining. Key aspects include:
Primary Lining: Shotcrete reinforced by wire mesh and rock bolts for immediate support and stability.
Excavation Technique: Drill and Blast with Observation methodology using instrumentation and 3D monitoring.
Tunnel Specifications
The Wavarle Tunnel features a ballast-less track and includes public refuge areas, a Tunnel control system (SCADA), lighting system, firefighting system, and ventilation systems meeting contemporary international standards. Additional specifications are:
Height: 7.323 meters
Width at Rail Level: 13.282 meters
Finished Cross-Sectional Area: 89.99 sqm
Gradients: R 1 in 254.623 & F 1 in 243.668
Degree of Curvature: 1-D (One Degree) with a curve length of 805 meters
Challenges and Achievements
During the excavation, significant challenges were encountered, including fractured rock masses with water seepage and minimal cover (as low as 12 meters). Two water streams cross the tunnel alignment at the low cover zone. Despite these challenges, an average underground excavation output of 175 meters per month was achieved through meticulous planning, with two rounds of blasting per day during the daytime as night time blasting is not allowed.
Collaborative Efforts
The project saw collaboration between several entities:
Technology Partner: CSIR-CIMFR guided the rock blasting process.
Design and Drawing Works: M/s AECOM
General Consultant: M/s RODIC-ARTELA (JV)
Executing Agency: M/s SDPL-TIPL-JMMIPL (JV), leveraging state-of-the-art technology and expertise.
A GIS-based project management system was implemented to monitor progress effectively.
Future Prospects
The successful breakthrough of Tunnel-2 represents a major milestone in the Panvel-Karjat railway project, paving the way for enhanced connectivity and transportation efficiency in the Mumbai suburban region.
Panvel-Karjat New Suburban Corridor:
Sanctioned Cost - 2782 cr
Progress: Physical: 50%
Target for Completion: December 2025