All language subtitles for Building Giants Series 2 3of3 Worlds Toughest Bridge 1080p

Narrator:
Stretching over two miles

Across
the saint lawrence river...

This is canada's newest
and toughest structure...

The samuel-de-champlain bridge.

With three months to go
before it opens,

Engineers are in a race against
time to finish construction.

Maiholt: The clock is ticking.

We're now in the final push.

Narrator: What technologies
make it strong enough

To handle
60 million vehicles a year,

And how does its design
beat extreme winter weather?

We unlock the engineering
secrets that make this structure

The most advanced bridge
in north america,

From its aerodynamic profile
that stands up

To the strongest winds
to a skeleton forged

From super-strong
corrosion-resistant materials,

To reveal what it takes to
build the ultimate super bridge.

-- Captions by vitac --
www.Vitac.Com

Captions paid for by
discovery communications

♪

Montreal, canada.

The nation's second-largest city
is a major hub

For business and commerce.

Montreal's success depends on
its big bridges

Spanning
the saint lawrence river.

They must move people and goods
between the city

And throughout the rest
of canada and the u.S.

To meet this need,

Montreal opened
the first champlain bridge

Over the
saint lawrence river in 1962.

The designers expected it
to last for a century.

But within 30 years,
the bridge started to crumble.

Now, after five decades
in service,

It needs around-the-clock
monitoring

And costly maintenance.

Alex szemenyei is part
of the team

Tasked with keeping
the old bridge operational

Until the new one is complete.

To get an idea of how much
these repairs

Have cost over
the past few years,

Since 2014, approximately
$300 million

Has been invested
into the bridge.

So we're looking at
approximately $50 million

To $60 million a year
being put into the bridge

Just to ensure
that it stays strong

And it stays standing
until the new bridge opens.

Narrator: Along the length
of the the bridge,

Flaked concrete
exposes rusted rebar beneath.

Engineers call this damage
spalling.

With the original bridge
crumbling apart,

The city is in dire
need of a replacement

To keep up with the economic
demand of the region.

But building and maintaining
big bridges in this part of

North america
is a huge engineering challenge.

Over the course of 12 months,

Montreal's climate
fluctuates wildly.

In summer, temperatures can soar
to a sweltering 95 degrees.

In winter, the air pressure
can plummet to minus-22 degrees.

Fast-moving ice floes overtake
the saint lawrence river

And freezing
winds batter the city.

To keep this metropolis
connected and moving

Through any kind of weather,

Engineers in montreal
are building this --

...The samuel-de-champlain
bridge.

It spans over two miles...

And costs over $3 billion.

♪

The bridge is designed using
innovative technology

Built into
its mighty structure

To stand up to everything
mother nature throws at it.

Ingenious cables
keep massive chunks of ice

From crashing onto cars
and pedestrians below,

A deck structure
that remains rock-solid

Against the strongest winds,
expanding joints stop the bridge

From cracking
as the temperature changes,

An ingenious drainage system

Flushes away
corrosive salty water

Before it can destroy
concrete and steel.

All these elements combine
to make

The new samuel-de-champlain
the ultimate bridge.

Construction began on the bridge
in 2015.

First, engineers installed
37 sets of pillars

Called piers on land and into
the saint lawrence riverbed

To create a base
for the structure.

Next, they laid a steel platform
on top of the piers.

Then they used giant
floating cranes

To place
9,600 concrete deck slabs.

Today, this elite team
works around the clock

To ensure the bridge
will be completed on time

For its grand opening.

Once finished, this vital
roadway must be able

To carry 60 million vehicles

And $15 billion worth
of cargo each year,

Stay open 24/7
in all types of weather...

...And survive for at least
125 years --

The life span the canadian
government specifies

For new critical bridges.

Chief engineer guy maiholt
leads the team

In charge of the herculean task
of building

This superstructure.

Maiholt: There's daily stresses
on us, the entire team,

To do whatever we can to get
the bridge open in time.

Narrator: The stakes for guy
and his team couldn't be higher

Because the cause of the damage
isn't going away any time soon.

In order to keep the roads
clear,

Montreal uses a crucial chemical
to keep their roads ice-free.

Ever since the 1960s,

The city covers its roads
and bridges with salt --

Over 285,000 pounds
of it every year.

Salt is an effective way
to melt ice,

But it destroys
concrete structures.

When de-icing salts melt
away snow,

They dissolve
into the liquid water,

Trickling down the side
of the bridge.

Over time, this salty water
seeps through the concrete

And contacts
the steel rebar inside.

The salt water contains
chloride ions.

These react with the steel,
causing it to rust and expand.

Eventually, the bridge
becomes so cracked

And damaged that large chunks
of it will begin to break away.

Without proper maintenance,

The bridge's steel skeleton
will become so corroded,

The entire structure
could collapse.

The challenge for guy
and his team is to make the new

Samuel-de-champlain
bridge 100% salt-proof.

To solve the problem, engineers
must completely rethink

The very fabric of this bridge.

Maiholt:
In planning the new bridge,

We really learn
from the old bridge,

And we were quite proscriptive
in the type of materials

To ensure that the bridge
would perform well

Over its intended
125-year design life.

Narrator: They choose to build
the skeleton of the bridge

From stainless steel rebar.

This chromium-enhanced metal
is 10 times more resistant

To corrosion
than traditional steel.

Marcel martineau's team
encases the skeleton

In the ultimate
protective concrete layer.

Engineers combine
stainless steel

Rebar and corrosion-resistant
concrete

To produce the bridge's
9,600 deck slabs.

Installing them onto the bridge
structure takes 22 weeks.

Today, marcel's expert team
races to fill the spaces

Between the slabs
with more concrete.

This mix is made with less water

And is much denser
than traditional concrete.

Workers use special machines
to eliminate air pockets

From the concrete to guarantee
its salt-proof qualities.

This section of roadway
is just one small part

Of an ingenious
drainage system.

The bridge's designers
engineered the structure

Like a giant sink

To reduce its concrete's
exposure to corrosive salt.

The shape and angle of
the deck's camber directs

Water towards drains located
along the edge of the roadway.

Water enters an intricate system
of pipes, up to 24 inches wide,

Running along the inside of the
structure to the nearest pillar.

The pipes release
the salty water

Three feet above the water line.

This reduces the amount
of concrete

Exposed to
the corrosive solution.

Once poured, the concrete
is left to cure for up

To seven days.

Workers cover the concrete
to protect it from the elements

And ensure it dries
at the right speed.

Once set, workers spray
the entire surface

With a synthetic resin.

This waterproof membrane is
part of a layered system

Specifically designed to prevent
the damage salt causes.

To ensure that we won't have
corrosion on this bridge,

We start with
a good drainage system.

We then have a thick layer
of asphalt.

We then have a waterproofing
membrane.

We then have high-performance
concrete,

Which is much more resistant
to salt penetration,

And then we have
the stainless steel rebar.

And the old bridge
had none of these.

Narrator:
The super bridge is now immune

To the damaging effects
of road salt.

But the mega-structure must
withstand more climatic extremes

To last 125 years.

What technology protects
this bridge

From montreal's major
temperature fluctuations?

And what is its secret

For beating the region's
destructive winds?

Narrator: In montreal, canada,
engineers have just three months

To prepare for the opening

Of the new
samuel-de-champlain bridge.

It must be robust enough
to serve the city every day

For a minimum of 125 years,

As mandated
by the canadian government.

If engineers get its
construction wrong,

This new bridge could suffer
the same fate

As its crumbling older neighbor.

One of the biggest challenges

Facing the new
bridge's engineers

Is building a structure

That can withstand montreal's
extreme temperature range.

In summer, temperatures
can reach up to 95 degrees.

In winter, the temperature
can plummet to minus-22 degrees.

Maiholt:
So you really have to look
at each individual component,

Understand how it's gonna behave
under the extended design life,

And then design it accordingly.

Narrator: Montreal's weather
cycle will have a big impact

On the city's new bridge.

Almost all the bridge's
components expand

When they heat up
and shrink when they cool.

Individually, the change
in size is miniscule,

But combined across
a two-mile-long bridge,

It can be dramatic
and catastrophic.

As montreal freezes in the
winter and warms in the summer,

The bridge can length by up
to 10 feet over the year.

Ignoring these fluctuations
could cause the bridge's deck

To buckle as it expands
or crack as it contracts.

To solve this problem,

Designers incorporate gaps
into the bridge deck.

The gaps are up
to 63 inches wide

And sit at eight strategic
places along the decks.

These allow the bridge to expand
freely into the open spaces.

The gaps stop the structure
from cracking,

But unfortunately, make it
impossible for vehicles to pass.

The solution are these
one-of-a-kind expansion joints.

They're designed to both fill
the gaps

And let the bridge flex.

Intensive factory tests
ensure each joint can stand up

To the extreme temperature
changes throughout the year.

Today, project manager
alexis lauzon

Oversees the final
joint's installation.

The expansion joint is
an important part of a bridge

To make sure that the bridge
can move freely

Throughout the seasons.

This expansion joint will take
a lot of abuse

Throughout the years.

Narrator:
Alexis' crew installs expansion

Joints into all eight gaps
in the bridge deck.

The sides of each joint

Attach to the ends
of two road sections.

As the bridge expands
or contracts, the joints,

Each 65 feet long,
move along rails.

They react to the bridge's
lateral and vertical movements.

Foam buffers ensure the joints
metal strips

Remain evenly spaced
as they move.

Spring bearings beneath
the strips distribute

The load of vehicles through
the bridge's concrete structure.

With three months to go
before the bridge opens,

Alexis and his team
are feeling the pressure.

The expansion joint that
we're gonna see today

Is quite heavy and quite big.

We have a 60-meter piece
that weighs around 16 tons.

The workers need to be
really meticulous

Because any wrong movement
could be fatal.

Narrator: A mighty crane lowers
the huge 32,000-pound joint

Into position.

The team removes some steel
obstructing the gap.

Then the joint slots
in perfectly.

As temperature changes make it
stretch and shrink,

Expansion joints will stop the
bridge deck from breaking apart.

But the deck's change in shape
presents

Additional engineering
challenges for this team.

Six huge deck sections
join to pier legs sunk

Deep into the saint
lawrence riverbed.

The piers could be stressed
and damaged

As the sections
expand and contract.

Additionally, montreal sits
in an active seismic zone.

Over the next 125 years,
the city will experience

At least
one major ground movement.

When it happens,
there's a real risk

The bridge will sustain
catastrophic damage.

If the structure were not
flexible, under a seismic event,

It would transfer
tremendous forces

Because the structure would be
much more rigid,

Which could potentially,
severely damage the piers.

♪

Narrator: Engineers install
special joints to allow the deck

To slip across its legs and stop
the bridge from breaking apart.

The bridge rests
on these bearings.

These bearings allow
the bridge to move.

Free to move and flex, the new
samuel-de-champlain bridge

Is now ready to withstand
extreme temperature fluctuations

And any future earthquakes.

The engineers' next challenge

Is to make sure
that this mega-bridge

Can combat devastating winds

And stand firm when hit by an
onslaught of deadly river ice.

♪

Narrator: In montreal, the new
samuel-de-champlain bridge

Is scheduled to open
in just three months.

This massive feat of engineering
is expected to serve the city

For at least 125 years.

The bridge has six lanes,

Which will carry over
one million vehicles each week.

But this behemoth accommodates
additional modes

Of transportation, too.

On one side, a pedestrian
walkway and bike path.

Down the center runs a rail line

Directly into montreal's
central station.

To accommodate all these
elements,

The deck is 190 feet wide.

But here, size makes you
a big target

For a powerful force of nature.

Winds in the saint
lawrence river valley

Can reach speeds of over
60 miles per hour.

♪

For the bridge to remain
standing,

Engineers space its pier legs
a mere 275 feet apart.

The short distance between legs

Reduces each deck span's
overall length

And bolsters the bridge
against fast-moving air

Pushing on its
massive structure.

But one crucial part
of the bridge

Needs a different method
of support.

Bridge piers cannot obstruct
the 475-foot-wide shipping canal

Running parallel to the river.

To span it,
engineers must suspend

A critical 780-foot-long section
of the bridge.

30 cables attached to a pair of

550-foot-tall towers
bear the load.

This leaves the waterway

Underneath the bridge
unobstructed by piers.

But suspending sections
of bridge deck from cables

Makes them vulnerable
to strong winds.

♪

The structure of some bridges
forces air faster

Over the top of their deck
than underneath it.

This creates an area of high
pressure beneath the bridge.

Just like an aircraft wing,
the deck lifts up,

Stressing the bridge's joints,
and damaging its deck.

Every time the wind blows,

There's a risk the new champlain
bridge will suffer damage.

Maiholt: The bridge
in the montreal environment

Has to be aerodynamically stable
in order to ensure

That the bridge
will not oscillate

Unexpectedly
under intense winds.

Narrator: Engineers deploy
an innovative solution

To eliminate the danger.

They design gaps in the deck

Between the bridge's road decks
and rail line.

These gaps vent and disrupt
the fast-moving air,

Preventing high pressure
from lifting the bridge

And damaging its deck.

On paper, the bridge looks ready
to withstand

The dangers
created by strong winds.

But wind presents another
engineering challenge

For a cable-stay bridge.

As history proves, build
a bridge that's too flexible,

And wind will tear it apart.

November 1940.

Tacoma narrows bridge,
washington state.

Four months after opening,
40-mile-per-hour winds

Cause the bridge
to twist and sway.

The movements became so violent
the bridge collapsed.

The cause was
a scientific phenomena

Called aeroelastic flutter.

Suspension bridges twist
fast-moving air

Into mini whirlwinds
that pull at the bridge deck.

The shape and weight
of most bridges

Means these vortices cause
only a slight movement.

But the shape of the tacoma
narrows bridges

Contained a critical flaw.

Due to its narrow,
lightweight deck,

The vortices caused
greater movement.

Sustained winds made the bridge
wobble and oscillate.

The twisting eventually
became so violent...

That the bridge collapsed.

To make sure the new
champlain bridge

Doesn't suffer the same fate,

Engineers submitted the bridge
to every possible wind condition

Before construction even began.

Maiholt:
You cannot really predict

How well the bridge
will be performing

Until you undergo some
very intensive wind modeling.

Engineers enlisted the help
of aerodynamics expert

Dr. Peter king.

His team at western university,
ontario,

Built a scaled-down
bridge model,

Costing nearly $53,000.

♪

They tested it in a wind tunnel
to predict how the full-scale

New champlain bridge
would behave.

King: The model is a complete
dynamic replica of the bridge.

So it has the right mass
properties,

The right stiffness properties,

And replicates all of the
dynamic motions of the bridge.

Narrator: The model withstands
simulated wind speeds of up to

112 miles an hour coming
from different directions.

To further improve
the bridge's aerodynamics,

Engineers modify the sides
of the back span.

This is the part of
the suspended bridge

That counterbalances the section

Crossing the shipping canal
parallel to the river.

They hope this will stop
the bridge

From shaking itself apart.

King: Here in the main span, we
have a solid pedestrian barrier

On the leading
and trailing edges.

Whereas in the back span,
it's completely open

And allows the wind
to go straight through.

Narrator:
Together, the different barriers
will disrupt the wind flow

Over the bridge
and reduce the pull on the deck.

The bridge is engineered
to beat the wind.

But there is still more mother
nature can throw its way.

How will the bridge
defend itself

From concrete-smashing
ice floes?

And what secret technology
stops ice

From falling onto the bridge
and crushing the cars below?

♪

Narrator: In montreal, the new
samuel-de-champlain bridge

Opens in
just a few months' time.

It must be ready to serve the
city every day for 125 years,

The minimum life span the
canadian government specifies

For new
critical infrastructure.

Workers battle freezing
temperatures

To get the bridge
finished on time.

On our goal to open the bridge
in June, the clock is ticking.

We're now in the final push.

Narrator: The super bridge
must survive over a century

Of brutal canadian winters

And the yearly onslaught
of powerful ice floes.

Montreal is subject
to winter freezing

Where the temperatures
can go down to minus-40.

This will mean that
the river will freeze over.

It can freeze up
to 0.9 meters thick.

This ice breaks up.

It will generate large floes of
ice that will impact the piers.

Narrator: Blocks of ice
can inflict critical damage

To big structures
that stand in their way.

♪

The current in
the saint lawrence river

Accelerates ice up
to speeds of 2.5 miles per hour.

A potential floe
traveling this fast

And measuring
approximately 150 feet across

And three feet deep
could strike the bridge

With the same force
as the weight of 10 trucks...

...Cracking and severely eroding
the concrete.

♪

This footage from the 1960s

Shows that ice floes
on the saint lawrence river

Have always been a problem.

♪

The old bridge is covered
in scars sustained

In battles with the ice.

Alex szemenyei's vigilant team
must react fast

To keep the crumbling
structure standing.

Szemenyei: On our piers,
we actually have steel lining

Just at the water level

To ensure that
when ice does hit the piers,

That the concrete itself
is protected.

But over time, sometimes
the steel lining disintegrates

With the water,
and concrete can be affected.

Narrator:
For the new samuel-de-champlain
bridge to survive,

It needs the strongest
concrete legs

Of any structure
across the saint lawrence.

All concrete is a mix of water,
sand, gravel, and cement.

Increasing the ratio of cement

To water raises
the concrete's density

And makes it super tough.

Engineers then add
a secret ingredient

That changes
the concrete's chemistry

To make it even stronger.

♪

At the atomic level,
when cement mixes with water,

The reaction creates calcium
silica hydrate,

Which bonds the concrete
mix together.

But the same reaction also
produces other particles

That disrupt the bonds,

Forming weak points
in the concrete.

When engineers add a chemical
called silica fume,

It reacts with
the disruptive particles,

Turning them into more
calcium silica hydrate,

Making the overall structure
stronger than ordinary concrete.

When construction work
first began on the bridge's

Piers back in 2015,

Engineers poured the bridge's
pier starters on land

And let them set until solid.

Then they used a floating
installer to sink 38 bases

Into the riverbed of
the mighty saint lawrence river.

Samuel-de-champlain bridge's
super-strong concrete

Makes it tough enough
to resist destructive ice floes.

But new challenges lay ahead.

How does this super bridge
prevent falling ice

That endangers lives?

And what cutting-edge technology
makes this bridge so intelligent

It knows when it needs help?

♪

Narrator:
Workers in montreal race

To complete the city's
new super bridge.

Yet only when all the cables
have been installed

Will the bridge
be ready to open.

Maiholt: Completing the cables
is significant

Because the bridge at that point
will be structurally completed

And the only things that
will remain are finishing works.

Narrator: The pressure is on
foreman jonathan simard

To finish the job.

Jonathan and his team
must install special sleeves

The encase the full length
of the bridge's 60 cables.

Cable sleeves protect the metal
inside from ice and rain.

But in winter, some sleeve
designs can create threats

That pose a danger
to both traffic and pedestrians.

2014, charleston,
south carolina.

The ravenel bridge closes
when large chunks of ice fall

On passing cars,
shattering their windshields.

Nine vehicles sustain damage.

It's the way water freezes
on the bridge's cable sleeves

That creates
the falling ice.

♪

Temperatures fluctuating
just above

And just below freezing
cause the problem.

Rain coats the sleeves
in water.

When the temperature drops
below 32 degrees,

The water freezes.

Temperatures rise, but not
by enough for the ice

To completely melt.

New rainwater accumulates
on top of the ice

And freezes when the temperature
drops below 32 degrees again.

Soon, a thick layer of ice
completely encases the sleeve.

The ice becomes heavier,
until it breaks away...

Crashing onto the bridge
deck below.

The designers of the new
samuel-de-champlain bridge

Must protect its cable sleeves

From shedding dangerous
large chunks of ice.

The ingenious fix is
a unique design

Running the length
of the cable --

A series of equally-spaced
hoops.

You can see that there
are circular ribs.

This is a bit different
from what you would see

On most bridges.

The idea here was with these
circular ribs,

It will help shed water
more efficiently.

Narrator:
The circular ribs are spaced
at one-foot intervals.

Because of the cable's
slanted angle, when it rains,

Water accumulates
behind the ridges

And harmlessly falls
on the bridge deck below.

The water freezes in chunks
trapped between the ribs.

The ice sheds in smaller pieces.

So when it falls
onto the bridge deck,

It's not dangerous to passing
cars and pedestrians.

Finally, the sleeves
are in place.

Now jonathan's team must thread
through the steel cable strands.

Future maintenance crews
will only have to replace

Individual damaged strands.

They will not have to switch out
the entire super-heavy cable.

Engineers use winches to
thread each strand one

By one up the sleeve and through
to cable anchors in the tower.

They then pull
the ends downwards

And secure them to the deck.

These are five times
the strength of normal steel.

The strands themselves are
actually doing all the work

In terms of supporting the
weight of the deck structure.

Narrator: The next challenge
is to tighten the cables to hold

The estimated 28 million-pound
weight of the bridge's span.

What ingenious tool makes
sure every cable

Is stretched
to the correct tension?

And what technology makes this
bridge intelligent enough

To know
when it needs maintenance?

♪

Narrator: In montreal,
workers race to ready the new

Samuel champlain bridge
for its grand opening.

Once complete,
the bridge must support over

One million vehicles
every week

And serve the city
for 125 years.

♪

Advanced super-strong materials
and an ingenious design

Make the bridge wind-proof,
ice-proof,

And flexible enough to cope

With montreal's
extreme temperature variations.

But its life span depends
on identifying

And repairing problems
before they become critical.

Limited access to inspect
the structure's interior

Is a big reason why the
old champlain bridge is failing.

Engineers
cannot see critical issues

Until they show up
on the bridge's exterior.

By then, it's too late to solve
the problem at the source.

At that point, all engineers
can do is patch up the damage.

So designers are building
the new bridge to have all-area

Access to avoid
these past mistakes.

Hatches, walkways, and crawl
spaces allow them to inspect

Every square foot of the
over-two-mile-long bridge.

♪

But engineers still need help
to identify potential problems

As early as possible.

Borja bailles leads a team

Tasked with making
the bridge intelligent.

Borja's team installs
435 sensors

That send data 24/7
to a central monitoring station.

Alerting humans to problems
early on

Is a big step to the bridge
achieving its mission

Of serving montreal
for 125 years.

♪

At deck level,
engineers race to thread

And tension
the last remaining cables.

The must tighten each of
the cable's 127 strands.

Mechanics deploy a special tool
to tension them one by one.

Maiholt:
They put a hydraulic jack,
which will pull the strand,

And then they'll stick
these wedges

That will lock
the strand into place.

♪

Narrator: Over the next 20 days,

The team pulls out
all the stops to finish the job.

The last cable plugs
in right on schedule.

♪

Two months later,
at 5:00 a.M. On June 24th,

The samuel-de-champlain
bridge opens.

The first vehicles roll westward
over the saint lawrence

On montreal's newest
and toughest crossing.

Over four years,
a 1,600-strong workforce

Has poured over 3 million
cubic feet of concrete,

Laid over 75,000 tons of steel,
tightened 1.2 million bolts

To span the mighty
saint lawrence river.

It's mission accomplished
for guy and his team.

To work on a project of this
magnitude is almost a dream,

Because you don't build these
sort of bridges very often,

And it's gonna be there
for many generations to come.

Narrator:
The samuel-de-champlain bridge
is tougher

And will carry more vehicles
than any other bridge in canada.

Built into its mighty frame
are five engineering marvels

That make it the pinnacle
of bridge design.

Ribbed cable sleeves stop
dangerous ice

From falling
onto passing cars.

A vented design keeps the deck

Steady against
the strongest winds.

Expanding joints
allow the bridge to flex

When the temperature changes.

Pier legs built from
super-strong concrete withstand

The force of crushing ice.

And innovative drainage gets rid
of corrosive salty slush.

This is a bridge that is big,

Tough enough to survive anything
mother nature throws its way,

And it's set to become
a montreal icon.

The samuel-de-champlain bridge
is built to be the ultimate.

♪