1. Tunnel Engineering for Indian Railways

2. Pir Panjal Tunnel

3. Pir Panjal Tunnel
The tunnel is almost straight, extending from north to south. It is 8.4m wide and 7.3m high.

4. Pirpanjal Tunnel
Pir Panjal (or T-80) is India's longest transportation railway tunnel at 10.96km.
The tunnel section is a part of the 202km Udhampur - Srinagar - Baramulla rail link project undertaken by the Northern Railways

5. Pirpanjal Tunnel
It operates 440m below the existing Jawahar Tunnel, which is the only road link from the region to the rest of India.

7. Tunnel engineering at a glance

8. 1. Topographic survey
Topographic survey done for 2000m length and for a width of 100m on either side of centre line of the tunnel
Resolution with a grid of size 25m x 25m
Gradient of 1 in 200 adopted in the tunnel throughout for easy drainage

9. 2. Geotechnical investigations
9 bore holes with a maximum depth of 51.0m below natural ground level
Rotary type boring machine with diamond bits was used.
Jointed basalt (above crown), breccia (in the Tunnel section), Amygdaloidal basalt, volcanic ash (below invert) etc are encountered.

10. 3. Field tests
(a) Electrical resisitivity tests
Current applied in the outer pair of electrodes
Potential difference measured at the central pair of electrodes
Resistivity governed by the amount of pore water and arrange of pores

11. 3. Field tests
(b) Pressure meter tests (Stress – Strain relationship of soil mass and deformation modulus, E)
Determine rock strength parameters, E for Basalt is 5000 MPa

12. 3. Field tests
(c) Lugeon tests (Permeability characteristics of rock mass
Permeability values are found to be low.
Assessment of grouting requirement.

13. 3. Field tests
(d) Seismic Tomography
Fast emerging powerful tool and precise in-situ determination of seismic velocities
Detailed information about the soil and rockmass properties
Separation of drill bore holes not more than 60m to give better resolution

14. 4. Tunnel Design
Design parameters:
Density
Water absorption
UCS
Core recovery
RQD
E value
Tensile strength
RMR
Q value

15. Tunnelling Video
Manual
Tunnel Boring Machine

16. TUNNELS IN SOUTH CENTRAL RAILWAY

17. Construction of BG Single line Railway Tunnel between Margutti (H) and Kamalapur stations In Bidar – Gulabarga section
Tunnel length: 1500 RM

19. Tunnel layout
Trolley refuge at every 100m
Main tunnel
Escape tunnel

20. AREA sqm

21. area:25.94 sqm

22. Tunnel radio system VIDEO

23. Thank you