All language subtitles for Building.Giants.S05E06.1080p.WEB.h264-CBFM_track3_[eng]

[narrator]
Deep beneath the Alps,
an elite team of engineers is

embarking on
an extraordinary mission.

They are attempting to build
the longest underground

railway tunnel
ever constructed.

To succeed, they must drive
giant tunnel drilling machines

through solid mountains.

Overcome unpredictable geology
deep beneath the surface...

Attention!

...and crushing pressure...

...to build a revolutionary
rail line that will transform

how Europe moves people
and goods

for generations to come.

This incredible mega tunnel
ranks in a league of ambitious

new engineering wonders that
are bigger, faster,

taller, and more advanced

than anything ever
constructed before.

This is the inside story of
the extraordinary challenge of

building these giants.

♪♪

France and Italy are two of
Europe's economic powerhouses.

Every year, over $100 billion
worth of goods,

from food to fuel,
moves between them.

But one of Europe's greatest
natural barriers

separates these two nations --

the Alps.

For centuries,
travelers and trade have had to

cross the mountains
the hard way --

through deep valleys,
narrow passes,

and winding routes.

But now,
engineers are attempting

something extraordinary.

A joint French and Italian
operation is building

a colossal 165-mile railway
line to link Lyon in France

with Turin in Italy.

When complete, it could cut
greenhouse gas emissions

by over one million tons,

and slash journey times across
the mountains from almost

four hours to under two.

At the heart of the project

lies its most
ambitious section.

Instead of going over the Alps,

the engineers are digging
straight through them.

This is the Mont Cenis
base tunnel,

a vast railway tunnel being
carved deep beneath the Alps.

Stretching over 35 miles,

it will be the longest railway
tunnel in the world.

And it must be ready by 2033.

It's the responsibility of CEO
Maurizio Bufalini to keep

this vast international project
on time and on budget.

[Maurizio] The cost of this
project is 11 billion euros.

But it's not simply a cost,
it's really an investment on

the future of Europe.

♪♪

Halfway between Lyon
and Turin, the tunnel will link

Saint-Jean-de-Maurienne
in France

to Susa in Italy,
over 35 miles away.

Engineers are digging two
enormous tubes,

each nearly 30 feet
in diameter,

side by side,
beneath the mountains.

One carries trains toward
France, the other toward Italy.

Every 1,100 feet,
passages connect the two

tunnels to create vital escape
routes in an emergency.

Above the tunnel, engineers are
also drilling four vertical

shafts, each hundreds
of feet deep,

to help ventilate the tunnel.

When complete, trains will race
beneath the Alps

at speeds around
125 miles per hour.

Work on this mega-project
begins in 2001.

It takes 14 years to excavate
almost 11 miles of preparatory

tunnels to study
the rock, the water,

and the immense pressures deep
beneath the Alps.

Now, engineers are preparing to

drive the two railway tunnels
through the mountains.

Overseeing this vast operation
is Constructions Director

Emmanuel Humbert.

In total, the railway project
requires workers to excavate

37 million tons of rock
across a 100 mile route,

enough to fill around 6,000
Olympic swimming pools.

This is how Emmanuel
and his team will do it.

First, engineers dig an 11-mile
network of four access points

and two tunnel portals at
either end.

They divide the excavation
into sections,

numbered from CO1 to CO9.

This allows engineers to work
from several different

locations at once.

Underground, they assemble
eight giant tunnel boring

machines, or TBMs.

These launch from different
points within the Alps.

Attacking the mountain
from multiple places

helps the engineers to reduce
construction time.

Eventually, these sections will
join to create

one continuous route.

♪♪

Engineers need
a mega machine to dig

all the sections of
this record-breaking tunnel.

Viviana is a tunnel boring
machine, or TBM.

She's almost 600 feet long
and weighs 2,500 tons.

The first challenge engineers
face is to get the machine onto

the site and into the tunnel.

A manufacturer in Germany
fabricates Viviana.

The engineers must transport
the machine more than 300 miles

from the factory
to the dig site

in Saint-Jean-de-Maurienne.

She's too big and heavy to
transport in one piece,

so workers break
her into sections.

A fleet of low loaders
transports the parts

to the CO7 tunnel site.

Safety vehicles shepherd
the truck for this hazardous

journey along narrow
country roads.

And through
small Alpine villages

with just inches to spare.

Now, the engineers need to
assemble Viviana.

First, they lower each of
her mega components through

an access point into
the tunnel below.

Each one weighs an average of
66 tons.

Next comes the assembly stage.

At the front of the machine is
the cutter head,

a wheel that weighs
roughly 330 tons

and carries 61 disc cutters.

This is the part of Viviana
that will grind the rock to

excavate the five
and a half mile section

of the Mont Cenis base tunnel.

The engineers successfully
assemble Viviana's critical

front section.

They turn the machine
90 degrees to access

the rock face.

It takes workers six months to

build the huge rear section of
the tunneling machine.

Viviana is now ready to punch
her way beneath the Alps.

Engineers in France and Italy
are digging the world's longest

railway tunnel
beneath the Alps.

Their next challenge is to
complete the first section of

the over 35-mile route

from Saint-Martin-la-Porte
to La Praz.

The nearly 600-foot-long tunnel
boring machine,

Viviana, is vital.

The tool engineers will use to
excavate the rock face is

the 34-foot-wide cutter head
at the front of the machine.

It consists of 61 cutters made
of tungsten.

The head completes up to three
rotations a minute to excavate

2,200 tons of rock in a day.

At its fastest, the machine can
excavate nearly 50 feet of

mountain every 24 hours.

But as the machine drives
deeper beneath the Alps,

the team faces
a dangerous challenge.

Every foot it cuts leaves

a stretch of excavated tunnel
behind it.

The weight of the mountains can
cause the newly opened ground

to close up.

This movement is
called convergence.

[Emmanuel speaks]

If the team fails to support
the excavation fast enough,

the mountain can
distort the tunnel,

drop unstable rock
onto the machinery,

or even trap
the machine underground.

This is the team's solution to

prevent a catastrophic
tunnel collapse.

A mechanical erector arm lifts
the precast concrete segments

into place.

Each curved segment weighs
11 tons.

Together, the segments form
a complete ring

that supports the tunnel.

Once the ring is complete,
hydraulic rams push against it

and drive the machine forward.

The machine then excavates
the next section of tunnel.

Behind the shield,
engineers inject grout into

the gap between
the lining and the rock.

The grout fills the void,
stabilizes the ground,

and seals the tunnel.

It's Guillaume Lefrere's
responsibility to make sure

the tunnel remains stable
for that long.

The machine's
robotic arm delivers

the first concrete segment.

It must place it with
millimeter accuracy.

Small errors that accumulate
over the length of the tunnel

could create
a dangerous misalignment.

[Guillaume speaks]

The machine's workers slot
the segment into position.

One by one, the arm lifts
and places

the remaining segments

to create a complete ring

around the inside
of the tunnel.

This rigid collar is strong
enough to resist the weight of

the mountain above it.

The next challenge for
the engineers is to ensure that

Viviana is heading in
the right direction.

It's critical that she follows

a precise route to
dig her section.

Any deviation will mean that
her tunnel will not line up

with the other tunnel sections.

Correcting the misalignment
will put the engineers

behind schedule.

Engineers in France and Italy
are digging the world's longest

railway tunnel
beneath the Alps.

The nearly 600-foot-long tunnel

boring machine, Viviana,
is vital.

To keep Viviana on track,
her driver, Christelle Desmons,

relies on a special digital
guidance system.

[Christelle speaks]

Engineers above ground
use GPS to plot

the tunnel's exact path.

Underground, Christelle tracks
Viviana's course relative to

the planned route.

The guidance system warns

Christelle when Viviana
drifts offline.

Christelle then adjusts
the angle of the machine to

correct the deviation and keep
the tunnel on course.

♪♪

For now, Viviana is right on
track, and she continues

tunneling towards the team
digging in La Praz,

five and a half miles away.

To stay on schedule,
the machines digging

the 35-mile-long Mont Cenis
base tunnel

need a steady supply of
concrete segments.

The tunnel's location creates
a big problem

for the engineers.

The nine sites above ground
are isolated

and sit in narrow
alpine valleys.

The CO7 site that supports

the tunneling machine Viviana
is no exception.

Trucking in concrete segments
will clog up the narrow

mountain roads with traffic
for a decade.

The engineers' solution is to
make what they need

from the tunnel itself.

Viviana excavates 2,200 tons of
material a day.

It's critical that the supply
of concrete components keeps

pace with the demand from
the tunneling team.

So the engineers build this --

the Illaz Transformation Plant.

It's a huge concrete factory
near the tunnel entrance that

turns the rock that Viviana

excavates into
building materials.

Project Director,
Sébastien Paulet,

oversees the operation.

Once the rock arrives
at the plant,

the recycling process begins
with quality control.

The plant feeds material into
powerful industrial crushers.

These break the rock down into
smaller and smaller pieces.

These pieces then pass over
a vibrating screening system

that separate them into
different grain sizes

for different purposes.

At every stage,
machines monitor the material

for impurities.

An industrial washer then
removes dust, clay,

and other unwanted material
from the crushed stone.

The final product is then dried
and emerges as aggregate.

The material this factory makes
is turned into concrete

segments for Viviana to line
the walls of the tunnel.

Workers will also use it
as backfill for stations

and viaducts along the route
between Turin and Lyon.

♪♪

The Mont Cenis base tunnel
project aims to process over

25 million tons of rock,
and to reuse at least half of

the excavated material.

The project underground could
slow to a crawl

if Sébastien's plant fails to
keep up with demand.

But for now, the entire
operation is on track.

Today, the team has produced
880 tons of aggregate.

[Sébastien speaks]

Engineers in Italy and France
are building the world's

longest railway tunnel
under the Alps.

Punching a hole this long
beneath a mountain range

presents them with
a big challenge.

The Alps are made from 15
different types of rock,

from hard, gneiss,
and metasandstone

to flaky layered rock
called schist

and fractured limestone that
holds vast amounts of water.

The hole a tunnel boring
machine makes through gneiss

holds its shape because of
the strength of the rock.

This makes it easy for the crew

to reinforce the tunnel
with concrete.

But a tunnel through
the wetter, less stable rock

is more likely to contract

as the huge weight of
the mountains above

pushes down on it.

This creates a big problem for
the engineers, as they discover

close to
the Saint-Jean-de-Maurienne

section of the tunnel.

[Maurizio] We have found
the ground very full of water.

And when you do the excavation,
you excavate ten meters.

In a few days, it was closing
of two meters.

It was incredible.

If you have a situation like
this with a tunnel boring

machine, the tunnel boring
machine has not the time to

create the ring, and so it will
be blocked in the mountain

and then will die inside.

A tunneling machine works best

when the geology
is predictable.

When it's not,
the engineers turn to

explosives to smash big holes
in the rock.

This method is called
drill and blast.

It gives engineers more control
because they can excavate

the tunnel in short sections
and inspect the ground

after every blast.

Drilling rigs bore dozens of
holes into the rock face in

a precise pattern.

Engineers position each hole
to control

how the rock will fracture.

Next, crews load the holes with
measured explosive charges.

Electronic detonators link
the charges and fire them in

a timed sequence.

The blast then ripples
through the rock

in fractions of a second.

The force drives forward,
breaks the rock face,

and protects the tunnel walls.

Crews clear the rubble.

Then, they spray shotcrete
onto the walls.

This quick-drying concrete
firms the tunnel

and stops it from contracting.

By using this method,
the team can carve out up to

13 feet of tunnel and 880 tons
of rock every day.

Constructions Director
Emmanuel Humbert oversees

this delicate process.

Emmanuel's team builds
a digital 3D profile of

the rock face using data from
surveys and laser scanning.

This shows precisely where
the explosive charges need to

go to ensure the rock
fractures cleanly.

A huge machine called a jumbo
drills the holes in the rock.

At the ends of the jumbo's
three hydraulic arms are

powerful drills that punch into
the rock simultaneously.

The jumbo uses the digital
pattern to drill the holes to

a precise position,
angle, and depth.

Each hole must follow the drill
pattern precisely.

Just one misaligned hole,

and the explosion could fail to
break the rock cleanly.

[Emmanuel speaks]

Next, workers load each hole
with an explosive charge.

Blasting the rock is a delicate

and perilous balancing act.

Too little power and the blast
will fail to break

the rock cleanly.

Too much and the tunnel itself
could be put at risk.

With the charges set,
the crew

retreats to a safe distance

and prepares for
the detonation.

Attention!

Nelson Gomes Pina and a small
team of miners assess

the results of the blast.

[speaks French]

[in English]
An excavator shovels
the hundreds of tons of blasted

rock into waiting dump trucks.

These take it to the Illaz
processing plant,

where the rock is turned into
aggregate to make concrete

segments that line the tunnel.

It takes the team two hours to
clear the debris and prepare

the face for the next cycle.

♪♪

Engineers building the world's
longest railway tunnel are

blasting their way through
the rock beneath the Alps.

Attention!

They're constructing the over
35-mile long tunnel in separate

sections that will join into
one length.

A team clears away the rubble

from a controlled blast in
tunnel section CO8.

The next challenge is to make
the freshly blasted tunnel safe

for the crews that will install
its concrete lining.

The team uses a mechanical
breaker to smash any dangerous

overhanging rock left
after the blast.

[machinery beeps]

The next task is to line
the tunnel

with a material that
will stabilize it.

The team uses a substance
called shotcrete,

a fast-setting concrete that
workers fire from special hoses

at high speeds.

It sticks to the rock and dries
quickly to form a hard

protective shell that helps to
hold the tunnel shape.

♪♪

[music ends]

With the shotcrete dry,
the tunnel is ready for

the next stage of construction.

It is the responsibility of
Georgiana Noreanu Bocur

to oversee the installation of

the tunnel's permanent
concrete lining.

The shotcrete is only
designed to ensure

the short-term durability
and safety whilst the works of

excavations are carried out.

If we don't install
the permanent lining all

around, the tunnel, yeah,
might cave in at long-term.

Georgiana's team faces
a big problem.

The extreme pressure nearly
1,500 feet beneath the Alps

forces groundwater
into the tunnel.

The team must stop this water
and make sure the tunnel is dry

before they line the wall
with concrete.

Water is a really big problem
in the tunnel because when it

gets in contact with
the concrete, it may infiltrate

and may create, like,
micro cracks, which may develop

in time and actually damage
the lifespan of the concrete.

This is why we are
installing all of

the waterproofing layers.

The waterproofing consists of
three special sheets --

a membrane that repels water,

a super strong textile that
prevents punctures,

and an inner layer that

protects the waterproofing from
jagged edges.

Now it's time to line
the tunnel with concrete.

First, the team cuts and welds
nearly 4,500 tons of steel

rebar to make the bottom curve
of the tunnel section.

They then pour 2,825 cubic feet
of concrete

at a time into this frame.

The steel strengthens
the concrete

and extends its lifespan.

We need to ensure a permanent
concrete lining at least

50 centimeters thick.

We have to build the tunnel

basically for a lifespan of
120 years.

So this is to ensure
the long-term durability

of the tunnel.

It takes the workers two hours
to finish the first stage.

They then raise the height of
the next concrete pours

until the whole tunnel
is lined.

By the end of the day,
Georgiana's team completes

32 feet of tunnel.

[Georgiana] Wonderful teamwork
again today!

We've got a big job ahead.

So this is one concrete pour
down and still a couple of more

kilometers to go.

But smashing through the rock
creates huge clouds of dust

and sometimes releases pockets
of toxic gases.

Prolonged exposure to these
could damage the health

of the team underground.

The engineers' solution is to
dig four ventilation shafts at

the halfway point
in the tunnel.

Technical manager Helene Roulet

oversees this part
of the construction.

[Helene speaks]

Helene's team must dig two
pairs of vertical shafts from

the surface down to
the tunnel below.

[Helene speaking]

Digging shafts this deep is
a huge engineering challenge.

This is how Helene's team
will do it --

engineers drill a pilot hole
from the surface to the tunnel,

about 1,600 feet below.

The hole is just
15 inches wide,

the size of a dinner plate.

If the drill drifts by more
than nine inches,

it could miss the tunnel.

At the bottom, crews attach
a giant cutting head

called a reamer.

This steel disk spans 17 feet

and carries dozens of
hardened cutters.

A winch pulls the reamer up
through the mountain.

As it turns, the reamer chews
through the rock and opens

a 17-foot ventilation shaft.

♪♪

The team positions the drill,

and it begins boring
the pilot hole.

Its target is the tunnel about
1,600 feet below.

After six weeks,
the drill bit breaks through

the tunnel's roof.

Next, a team inside the tunnel
constructs the reamer

from 32 special discs.

The team above ground spins
these cutters and pulls them up

to bore out a huge 17 foot
diameter shaft.

Helene's team constantly
monitors the reamer

to make sure it cuts the rock
cleanly and efficiently.

It takes the team two
and a half months to excavate

the over 1,600 feet
to the surface.

The engineers' next challenge

is to secure the walls
of the shaft.

Loose rock could fall
and injure the workers below,

so they must find a solution.

Engineers in France and Italy
are digging the world's longest

railway tunnel
beneath the Alps.

Their next challenge is to
secure the walls to the shaft.

Loose rock could fall
and injure the workers below.

Their solution is to spray
shotcrete onto the surface of

the shaft to firm it up.

Dangling a human on a rope with
a shotcrete hose is

unsafe and impractical,

so Helene's team uses
this special robot.

Today, the engineers are firing
it up for the first time.

Workers connect the shotcrete
pipe to the robot

and lower it into the hole.

The robot's pilot deploys
its four legs to brace it

against the wall of the shaft.

[worker] OK.
Down.

[machinery honks]

The robot gets to work.

The robot's nozzle sprays
an even coat of shotcrete onto

the rock as it descends.

When the robot completes 490
feet of shaft, workers install

super strong metal ribs to
reinforce the shotcreted walls.

The ribs form a shell that
strengthens the unstable

sections of the shaft.

It allows crews to
stabilize the wall

before they install
the permanent lining.

It takes Helene's team
and the robot six months to

shotcrete and reinforce
the first shaft.

Once all four shafts are
complete, they will supply

fresh air for the crews working
deep beneath the Alps.

And when the tunnel is
finished, they will become

vital access points
to rescue passengers

in the event of an emergency.

The Mont Cenis base tunnel is
one of the most ambitious

engineering projects
ever attempted.

Foot by foot,
the teams building it are

getting closer to
completing the longest

railway tunnel in the world.

You can see the tunnel
and the permanent works growing

under your eyes.

To see the results of your own
work every day, it's amazing.

From the 2030s, high speed
trains will use it to race

between Lyon and Turin
in a fraction

of the time it takes today.

But this is not only for
people today.

This is really an opportunity,
a big opportunity for our sons

and daughters in the future.

These huge peaks divided Italy
and France for centuries.

Now, engineers are punching
a new path under them that

brings Europe closer together.