In this presentation all components are described.

1. ABHISHEK S. KULKARNI
GOV.POLY.,SOLAPUR.
CE-5G(R)
TUNNEL BORRING MACHINE
project guidance:
gaikwad sir

2. TUNNELBORRINGMACHINE

3. TUNNEL BORRING MACHINE

4. CONTENTS
Introduction
 Advantagesof TBM
MachinePartsof tbm
Economicsof Tunnel
Typesof TBM
MainBeamTBM
EarthPressureBalanceTBM

5.  INTRODUCTION:
 TBMexcavatetunnelswithcircular/ throughvarietyof geologicalconditions.Tunnel
diametercanrangefrom1-15m.
 Oneof thefirstTBMbuiltwasusedfortheconstructionof Hoosactunnel-Railroad
tunnelintheNorthernBerkshireto wnsofFloridaandNorthA damsConstructedof
castiron, it managedto drill10feetbefore breakingdown.
 BMsarepreferredinurbantunnellingandundergroundminingoverconventional
methods.

6. *Tunnel: -
*Artificial underground passageto by pass obstacles safely without
disturbing the over burden.
*Opento sky passage excavatedthrough hugesoil mass of obstacle
in required directions to connect two roads or railways.
*Over-ground construction to crossover obstacles withoutdisturbing
the natural way belowit.

7.  ADVANTAGES OF TBM:
 Reduced disturbance to the surrounding soil
 Produce a smooth tunnel wall reducing ventilation requirements
 Reduce cost of lining
 Improved personnel safety
 Working speed-6 times greater
 Hence, wherever speed and safety becomes the main criteria, use of
TBM despite its heavy capital cost is preferred.

8. History of Tunnel Constructed
 Egyptians and Babylonians –4000 years ago
 length –910 m ; width –3600 mm ; height –
4500mm
 Channel Tunnel –linking Britain & France –
1994
 length –50 km ; undersea component -39 km
 Consist of 3 parallel bores of 50 km length
interconnected every 375 m by cross
passages

9. Economics of Tunneling
 Nature of Soil
 Requirements of fill
 Depth of cut > 18m –tunnelling
 Desirable when
 1. Rapid transport facilities
 2. Avoids acquisition of land
 3. Shortest route connection
 4. Permits easy gradient & encourages high
speed
 5. On strategic routes

10.  MACHINE PARTS:
 A TBM typically consist of
 Cutter head
 Shield-metal cylinder serving as temporary support
structure while excavation
 Trailing support mechanisms •Precast concrete segment
handling & installing devices •Conveyor belt system for
muck removal •Control Cabin •Supply tanks, exhaust fans
etc.

11. Classification of Tunnels
Based on purpose
Conveyance Tunnels
Traffic Tunnels
Based on type of material met
with in construction
Tunnels in Hard Rock
Tunnels in Soft materials
Tunnels in Water Bearing Soils

12. INVESTIGATIONS
Investigations prior to planning
Investigations made at time of
planning
Investigations made at time of
construction

13.  TYPES OF TBM: -
 Based on no. of shields used:-
 1.Main beam TBM
 2.Single shield TBM
 3.Double shield TBM
 Based on the face supporting technique used :-
 1.Earth pressure balance TBM
 2.Bentonite slurry TBM
 3.Compressed air TBM
 4.Fluid balance TBM

14. Investigations of Prior Planning's
 Geological Investigations –relation
between bed rock and top soil
 Morphology, Petrology, Stratigraphy
 Electrical Resistivity Methods –
positions of weak zones -faults, folds
and shear zones

15. Investigations made at time of
planning
 Drilling holes by percussion, rotary
percussion and rotary
 Rotary or Rotary Percussion methods –loose
soils
 Rotary Drilling –rocky soils
 Spacing –300-500m ; reduced to 50-100 m in
geologically disturbed areas
 Lateral Spacing –10-15m from C/L of tunnel
 Depth –20-50 m deeper than proposed invert
level of tunnel

16. *MAIN BEAM TBM*

17. *SINGLE SHIELD TBM*

18. *For detailed undisturbed
observations, shafts can be
excavated
*Shafts –vertical or inclined tunnel
excavated to reach and to get
information for the area surrounding
proposed tunnel and tunnel section
*Section of 3m x 1.5 m to 3 m X2m
*Minimum depth of excavation
*Temporary and Permanent Shafts

19. Setting out of Tunnels
 Setting Out -Making the centre line or
alignment of any construction work on
ground
 Setting out centre line of tunnel by 4 stages:
 Setting out tunnel on ground surface
 Transfer of Centre line from surface to
underground
 Underground setting out
 Underground Leveling

20. Settingout tunnel on ground surface
*Running an
open traverse
between two
ends of
proposed
tunnel

21. Underground Levelling
 Reduced Levels of X & Y are found
 Plumb bobs are suspended through X and
Y to touch marked points X & Y on invert
level of tunnel
 Plumb bob with wire is spread on ground
for comparison with steel tape ( say 8 m)
 From RL of X, subtract 8 m to get RL of
point X on invert
 Taking this level as BM, leveling is
performed underground

22. SHAPE OFTUNNELS
*Circular Section:
*To withstand heavy internal
or external radial pressures
*Best theoretical section for
resisting forces
*Greatest C/s Area for least
perimeter
Sewers and water carrying
purposes

23. Tunnel BORRING MACHINE
DETAILS

24. *DOUBLE SHIELD TBM*

25. • Grip per Shield TBM used to create an under ground
laboratory within Yucca mountain.
• Manufacturer-CTS , Kent Washington
• Length-140m,
• weight-720tons,
• diameter-7.62m
• Maximum advance rate-5.3m/hr
• Power-12 electric motors generating 3800 HP

26.  EARTH PRESSURE BALANCE TBM :
 Suitable for urban tunnelling
 Designed for soft ground containing water under pressure
 Controls subsidence of tunnel face by adjusting the pressure
inside cutter head chamber so that it get balanced with
outside pressure
 Working area completely sealed against outside fluid
pressure
 High advance rate ,simple muck removal
 Limited to 6 or 7 m diameter tunnels

27. THANKYOU