Tunnelling equipment

Tunnelling equipment

1. TUNNELLING EQUIPMENT ( Equipments for Under-ground Works) Tunnelling Equipment 1

2. Purposes of Tunnelling For underground traffic i.e. passageways for railroads and for automotive vehicles Converns Accesses to mines Subways , underground parking Conduit for utility se rvic es, like laying electric and telephone cables etc Vertical / Inclined shafts Conduit for water i.e. for diversion of rivers while constructing hydroelectric plants, and also for providing water supply or drainage system

3. Number of Tunnel Entrances Tunnels of short length upto few hundred metres are driven from one entrance only. Longer tunnels are driven from both sides to avoid problems related to long time required to completing the tunnel, excessive haulage distance, high haulage costs, ventilation etc. For still long tunnels it is desirable to provide intermediate openings for facilitating removal of muck and water and supply of materials, utilities, air for ventilation etc. Tunnelling Equipment 3

4. Shapes of Tunnels Circular Egg shaped or semi circular Horse shoe Vertical walls with arch roof Tunnelling Equipment 4

5. Methods of Tunnel Driving Full F ace Heading Heading and Bench Method Drifts Method Pilot T unnel Method Tunnelling Equipment 5

6. FULL FACE HEADING Tunnelling Equipment 6

7. HEADING & BENCH METHOD Tunnelling Equipment 7

8. DRIFT METHOD Tunnelling Equipment 8

9. PILOT TUNNEL METHOD Tunnelling Equipment 9

10. GROUTING Grouting is done in order to tighten up the loose rock. Tunnelling Equipment 10

11. ROCK BOLTING Rock bolts are provided in holes drilled into the Stable rock to assist in Supporting load of loose rock. Tunnelling Equipment 11

12. Why TUNNEL BORING MACHINES (TBMs) ARE Used ?? At present tunnelling in our country is being mostly done by conventional drilling and blasting method which is very time consuming . In drilling & Blasting technique, it has been experienced that only 25% of explosive energy is utilised in actual rock breaking process and rest is dissipated through surrounding medium. Tunnelling Equipment 12

13. TUNNEL BORING MACHINES (TBMs) Tunnelling Equipment 13 TBMs loosen the earth the rock continuously in the entire section of the tunnel, into cuttings and convey to the rear of the machine, where it can be loaded into muck trucks or dumpers or on to conveyor belts for the transportation to the ultimate disposal site.

14. Tunnel Construction Using Drill & Blast Tunnelling Equipment 14

15. MUCK LOADING (MUCKING) Mucking is the operation of loading the broken rock or earth for removal from a tunnel . Mucking is done by hand in small tunnels, drifts and pilot tunnels. Mucking operations can be performed by power shovels, tractor loader, mucking machines etc. Tunnelling Equipment 15

16. Muck H auling Equipment Front E nd Loaders Small D iesel Trucks/Tippers Rear Dump T rucks Belt Conveyors Pumps & Pipelines Rail Haulage E quipments

17. TYPES OF TUNNELING MACHINES ROTARY TYPE It consist of a wheel fitted with either teeth or disc cutters or roller bits which removes in either direction around the central shaft. These are primarily used in firm underground formations including hard rock applications. OSCILLATING TYPE They are used for soft or semistable formation . These machines are used in changeable ground conditions or where underground formations vary. Tunnelling Equipment 17

18. Tunnel Boring Machines Advantages Higher speed of excavation Less manpower requirement Reduction in tunnel supports requirement Muck removal is continuous, fast,safe and convenient Produces smooth and round opening Disadvantages High Investment cost Long delivery period in purchase and importation Repair of the mole is cumbersome and time consuming Tunnelling Equipment 18

19. MODERN TRENDS IN TUNNELLING Use of Laser B eams Rock Bolter Wet S hotcrete Machines

20. Thank You Tunnelling Equipment 20