New Delhi: The USBRL is a National project undertaken by the Indian Railways for construction of broad-gauge railway line through the Himalayas, with the aim of connecting the Kashmir region with rest of the country. On December 15th, 2022, a major milestone has been achieved by executing the breakthrough of Escape Tunnel T-49 between Sumber and Khari Stations on the Katra –Banihal section of the USBRL project. The length of the escape tunnel is 12.895 km. This is the longest escape tunnel of India and the line and level of the tunnel are precisely achieved during the breakthrough of the Escape Tunnel.
Several Challenges were encountered in the course of construction such as shearzone, perched aquifer, and highly jointed rock mass, rock problems of excessive squeezing and heavy ingress of water. On the north end, the tunnel alignment passes through very weak shear zone of carbonaceous phillite. The tunnel mining was very challenging and several surprises were met during tunneling. Excessive deformations were recorded during tunneling at several locations between Kundan and Seeran, but these challanges were successfully tackled professionally.
The team of experienced engineers of Indian Railways successfully negotiated all challenges and achieved the major milestone of the breakthrough of the Escape tunnel. During the construction activities of the tunnel, more than 75% of workers from nearby villages were engaged in various construction activities, thereby ushering a positive change in the overall socio-economic landscape of the region.