Digital Issue 2010 trial preview 150 dpi

MEGA PROJECTS
10 years from the original project timeline.
The original plan, set in 1998, was to have
the baseline railway operating in 2007.
As it is, TBM excavation of the longest
drives for the main tunnels started from the
Bodio portals in 2001 with drill+blast work
starting from the base of the deep access
shaft at Sedrun in 2002. Work on the
shorter TBM drives from the north Erstfeld
portals started in 2006. The project is now
scheduled to open at the end of 2017.
When the Gotthard Base Tunnel
During the course of realising the
massive Gotthard Baseline project,
many different contractors and engineering
firms, many thousands of workers, and
legions of different suppliers and equipment
manufacturers contributed to the effort.
Three construction contracts were let
for the main tunnels and their passages
and chambers.
• At Sedrun, the consortium of Implenia/
Frutiget/Bilfinger Berger/Pizzarotti
completed 11km of drill+blast
headings at the bottom of the two
800m deep access shafts.
• At the south, TAT, the Tunnel AlpTransit
Ticino JV comprising Implenia/
Alpine Bau/CSC Impresa/Hochtief/
Impregilo completed two lots and
operated two Herrenknecht TBMs
running parallel for about 14km from the
Bodio portal initially and then carrying
on into the 11km long drives from the
Faido access adit to breakthrough into
the Sedrun drill+blast work.
• From the north, the AGN,
Arbeitsgemeinschaft Gotthard-
Basistunnel Nord JV of STRABAG
AG of Switzerland and Austria,
managed the two further Herrenknecht
TBMs on the project for the initial
10.7km of tunnel from the Amsteg
opens in 2017, travel time between Zurich
and Milano will be shortened by one hour.
In addition, freight trains will be able to
travel the straight, flat tunnel alignment
with twice the load and at twice the
speed. People and goods will cross the
Alps faster, more safely and in a much
more environmentally friendly way. The
breakthrough of the first running tunnel
of the twin tubes through the base of
the Alps is a historic and record-setting
achievement.
adit to breakthrough with the Sedrun
drill+blast work and then the 7.1km
parallel drives from the Ersteld portal
to Amsteg.
Herrenknecht AG supplied four gripper
rock TBMs of 8.8m to 9.5m diameter to
the consortia for the north and south lots.
The machines excavated a combined total
of 85km of the 2 x 57km long twin tube
complex. For development works and the
central Sedrun drill+blast excavation, fleets
of Atlas Copco and Sandvik jumbos were
used with their support systems.
Muck haulage behind the advancing
TBMs was via long continuous conveyors
supplied by H+E Logistics but the supplyline
rail-bound workhorses of the longdistance
headings teamed once again the
familiar duo of SCHÖMA locomotives and
Mühlhäuser rolling stock. SCHÖMA supplied
more than 125 powerful locomotives to
the project. Mühlhäuser delivered more
than 500 units to the different contractors
including wagons, concrete remixers, flat
cars, man-riders and specialised ambulance
cars to assist in any emergency.
Concrete admixtures, shotcreting
machines and a fire protection mortar
were contributions by BASF MEYCO to
the different construction contracts.
DELVO ® Crete Stabilizer 10 slowed
The last of the four Herrenknecht
TBMs that have excavated much of the
total underground works was working
towards the very last breakthrough for the
entire project in March 2011. •
References
• Breakthrough milestone for Gotthard Base
Tunnel - TunnelTalk, September 2009
• Gotthard TBM safely across the Piora
Mulda - TunnelTalk, Nov 2008
• Bodio tunnel lining wurms - Switzerland -
TunnelTalk, Dec 2004
Concrete contributions to a mammoth undertaking
down cement hydration to ensure an open
time of four to six hours while GLENIUM ®
superplasticizers maintained workability after
long distance transportation and exposure
to the high temperatures in the interior of the
mountain. The combination was used for
cast final lining as well as shotcrete. MEYCO ®
SA 160 accelerator was added to shotcrete
for fast solidification.
MEYCO ® Fireshield 1350 fire protection
mortar was supplied to protect the concrete
linings from spalling damage in the event
of an in-tunnel fire in the Bodio tunnel
section while MEYCO ® Potenza and Oruga
shotcreting robots were delivered in numbers
to the Erstfeld and Sedrun headings.
To the effort Bekaert supplied volumes
of Dramix ® steel fibre for shotcrete
reinforcement as well as its Duomix® M6
Fire protection polymer fibres.
Many different sets of formwork were
supplied to the project, several of the
specialist pieces by Doka of Austria. For
the Erstfeld lot its equipment lined the two
large span Y-branch crossover caverns.
The congratulations of all in the
international tunnelling industry goes
to the workers, suppliers and all the
managers involved who teamed together
to bring the project to its successful endof-excavation
milestone. •
Among principle suppliers (clockwise from top left): Herrenkneckt gripper TBMs; Schöma locos and Mühlhäuser concrete
remixer cars; Doka formwork; Bekaert steel and polyfibre as well as BASF MEYCO concrete admixtures
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TunnelTalk ANNUAL REVIEW 2010
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