egress, commonly at each end.
A tunnel may be for road traffic,road
traffic,canal,hydroelectric station,sewer etc.
the longest tunnel, of any type, in the world
at 137 km (85 mi)
it is very useful where bridge fail to fulfill
requirements like in sea ,in urban area
and in mountains.
in war time it is much difficult to destroy
a tunnel but destruction of bridge is too
easy.
INTRODUCTION
OR SOME OF THE FOLLOWING OPERATIONS:
Probe drilling (when needed)
PROBE DRILLING
This type of drilling is done in order to find out suitable method for drilling
It consist of drilling in sample, by various method to find most suitable
It is necessary part of all drilling operation .
GROUTING
support to drilled mine.
of water ,cement ,color tint and
sometime fine gravel .
at an archaeological site.
importance of a site before digging .
This is performed by experts in a scientific way.
Many governments grants permission for tunneling
after finding a go certificate in excavation.
SUPPORTING
After initial mining , tunnel need supports for further processing .
For the sake of life a perfect planning is needed for support.
In ancient time timber and masonry were the main methods.
 
TRANSPORTATION OF MUCK
In ancient time transportation was done by steam engine and by Manual transport.
Today it is done by modern methods and process is automatic .
TBMs are also come with proper arrangment for the transport of muck.
LINING OR COATING
methods like polishing ,painting to prevent wear
and tear and corrosion.
 being used.
DRAINING
Draining is the process to remove the water or other liquid from working site
Very important where water level is very high.
Pumps and pipes are used for this purpose.
VENTILATION
Proper ventilation is required for safety of workers.
 
CLASSICAL METHODS
Among the classical methods are the Belgian, English, German, Austrian, Italian and American systems. These methods had much in common with early mining methods and were used until last half of the 19th century.
Excavation done by hand or simple drilling equipment.
Supports were predominantly timber, and transportation of muck was done on cars on narrow gauge tracks
Progress was typically in multiple stages
The lining would be of brickwork.
These craft-based methods are no longer applicable.
 
THE ENGLISH METHOD
 
THE AUSTRIAN (CROSS-BAR) METHOD
 
THE GERMAN METHOD
(core-leaving method) provided a series of box headings within which the successive sections of the side walls of the tunnel were built from the footing upwards, thus a forerunner of the system of multiple drifts. The method depends on the central dumpling being able to resists without excessive movement pressure transmitted from the side walls, in providing support to the top 'key' heading prior to completion of the arch and to ensuring stability while the invert arch is extended in sections.
THE BELGIAN SYSTEM
(underpinning or flying arch method) started from the construction of a top heading, propped approximately to the level of the springing of the arch for a horseshoe tunnel. This heading was then extended to each side to permit construction of the upper part of the arch, which was extended by under- pinning, working from side headings. The system was only practicable where rock loads were not heavy.
 
The principal problem to be solved in connection with this
construction method is to how to maintain surface traffic, with
the least disturbance during the construction period. One
method is to restrict traffic to a reduced street width, another
to direct traffic to a bypassing street.
Another way of supporting the sidewalls of open trenches is to
substitute sheet-pile walls by concrete curtain walls cast under
 bentonite slurry (ICOS method), and using steel struts. This is
especially a requisite in narrower streets trimmed with old
sensitive buildings with their foundation plane well above the
 bottom level of the pit. This type of trench wall becomes a
requirement for maintenance of surface traffic due to the
anticipation of vibration effects potentially harmful to the
stability of buildings with foundations lying on cohesion less
soils.
DRILL AND BLAST
1.Before the advent of tunnel boring machines, drilling and blasting was the
only economical way of excavating long tunnels through hard rock, where digging
is not possible.
 
 
TBM
Various size Tunnel Boring Machines(TBM) are used for drilling a vast
type of tunnels .
Transportation of muck , supporting and all other actions are done
automatically.
Very useful in boring tunnel where all other methods fail.
A main method in use in now a days.
 
 
• THEY DO NOT BLOCK THE ROUTE FOR SHIPS
 
IN ALREADY EXISTING BODIES SUCH AS ROADS ,RAILWAYS
• IN THIS METHOD ESPECIALLY MADE PIPES ARE PUSHED BY A HYDRAULIC RAM IN GROUND
 
dictated by :-
Local Experience And Time/Cost Considerations
Limits Of Surface Disturbance
 
THE OTHER SIDE Beside of many security measures , tunnelling is still not fool proof.
Failure of automatic system will cause deadly results as depicted in
Hollywood flick Die Hard 4.0.
High cost than bridges, but more fruitful from previous.
 
the rock
3. Detonating the explosive causes the
rock to collapse
tunnel surface is reinforced
eventually create a tunnel
 
The positions and depths of the holes and the amount of explosive in each hole are determined by a carefully constructed pattern
 
tunneling machine
the tunnel for placing of explosive
• Machine is computer controlled
time with direction or angle
precisely set
smaller sections for the sake of easier control
and safer supporting during excavation
The newly formed surfaces are often required
to temporary supported by girder sections,
shotcrete, nails or anchors.
Tunnel Method
and blast process, the newly
formed tunnel surface is to be
lined with an in-situ concrete
lining to stabilize the exposed soil
or rock faces
formwork used to form the in-situ
concrete lining.
concept of New Austrian
Tunnel Method
The tunnel boring machine for the forming of
the 3.8m diameter tunnel tube on Butterfly
Valley side.
• Close up of the cutter head.
• The cutting disc can cut into hard rock
and the granulated spoils will be collected
and removed by a conveyor system that is
positioned immediate at the back of the
cutting head.
Soil disposal wagons at the disposal area on
Butterfly Valley side portal. The spoil will be
kept at this location waiting for the removal
off-site by dumping vehicles.
Arrangement of the portal as viewed from the
tunnel exit. The spoil disposal
area is located on the right side of the exit with
rail track heading to that
direction. Rail track on the left is the depot and
servicing centre for the soil
disposal wagons, as well as for general loading
and unloading purposes.
A view of the tunnel interior with the partly
formed lining, tunnel supporting girders, rail
track for soil disposing wagon, ventilation
hose and other supply pipe lines etc.
 
Tunnel Construction using Tunnel Boring Machine (TBM) • A similar tunnel boring machine employed for the forming
of a cable tunnel for the Hong Kong Electric on the Hong
Kong Island side.
or even slight adjustment of its heading direction.
 
 
The working principle of the mixed-ground earth pressure
 balanced tunneling machine under the open mode and earth
pressure balanced mode.
 
 
Tunnel Construction using Tunnel Boring Machine (TBM) The cutter head is
 being connected to
were constructed in the
reclaimed land of TKO New Town
 
 
of traveling-type tunnel formwork
Tunnel Construction using Immersed Tubes Western Harbour Crossing is constructed
using precast oncrete immersed tube
sections. A total of 12 sections have been
used, each measures 113m x 33.5m x 8.5m
high and weighs about 35,000 tons. The
photo shows one of the 3 batches of
immersed tubes being formed in the casting
yard at Shek O, HK
 
Tunnel Construction using Cut-and-Cover Method The arrangement of the approach tunnels on West Kowloon
Reclamation side. As can be seen here, the ventilation building also
serves as the coupling structure to receive the first approaching
immersed tube. After the tube being connected, the water embraced by
the elbowing land would be filled to
secure the coupling connection and make the tube land-bound.
 
Tunnel Construction using Cut-and-Cover Method The second immersed tube being towed to the launching position for
sinking and connecting onto the first tube. The first tube at this stage
has already been firmly positioned at the seabed and cannot be seen on
the surface.
Touching up of the land surface
after the completion of the
immersed tube connection. Note
tunnels for the Airport Railway on
the right hand side of the
reclaimed land.
Mucking tools
diesel drive into the tunnel and at the tunnel face
using emission free electric motor
Conveyor belt to rapidly move back the
excavated material
formations
As loading machines with typical drill and blasting
heads
•Upper carriage with short tail permits large swing radius
•Along with swing bucket dipperstick exhibitshigh break out forces
•Turbo diesel engines
•165kW diesel engines with high pump capacity allows use of
powerful drill rigs
place in the same track
Slewing of conventional crawler not required
Loading capacity – 3-4 cu.m. per min
 
Demolition
conditions
Low noise cutting operation,
low vibration, smooth and
Universally rotating and swiveling
For underground transport- quick disassembly & reassembly