Original subtitles

[music]

[Male narrator]: How do you build a glass bridge

out over the Grand Canyon?

We all thought it was an April Fool's joke.

[Narrator]: What engineering secret makes a library

defy the laws of gravity?

[Ellie]: It's just completely bonkers.

It looks like it's gonna fall down at any moment.

[Narrator]: And how do you build a museum tough enough

to survive anything Mother Nature throws at it?

[Eric]: We had to design inside the piers

for the impact of a car

travelling at 2 metres per second

[Narrator]: This is the age of the extraordinary.

[Hayley]: It's like one of those insect-eating plants,

only enormous and white.

[Narrator]: Where ingenious engineers have unleashed

unchecked creativity.

Now their secrets are revealed

as we discover the amazing stories of their construction.

This is an incredible feat of planning and engineering.

[Narrator]: To try and understand...

how did they build that?

How to take the most breath-taking selfie

at the Grand Canyon is a question

that's been troubling minds since...

Well, since selfies began, really.

We've gone up in a helicopter. We've tried the VR simulator.

But to really get the heart pumping,

how about walking out over the canyon and staring down,

past your shoes, into the gaping 4000-foot abyss?

"Come on, Jay, that's impossible!"

I know that's what you're saying.

Impossible? Says who?

[Narrator]: The Grand Canyon in northern Arizona.

One of the Seven Natural Wonders of the World.

Created by nature, its stunning beauty

has made it one of the most famous and most visited places

in the United States.

Back in 1903, President Teddy Roosevelt declared,

"Leave it as it is."

He said, "You cannot improve on it.

The ages have been at work on it and man can only mar it."

And for more than a century,

the spirit of that idea held true

with the millions of visitors taking a peak over the edge,

white water rafting through it,

or for the lucky few, taking it all in from the air

That is, until in 2003,

when the Hualapai tribe decided to build

a very special viewing platform

that's anything but run of the mill.

[Hayley]: When you're building in a landscape

as beautiful as this, everything has to be perfect.

[Narrator]: So they created a glass-bottomed walkway

that stretches 70 feet out over the edge.

It's just really cool how you can look down

and see straight down.

Oh my goodness, this is scary.

I've seen the sign that says, "I chickened out."

Well, it pushes you out into the canyon itself.

So it's a very nice feeling.

[Narrator]: Without visible supports,

the structure appears to float

4000 feet above the canyon floor.

It's a dizzying engineering achievement

[Corina]: The skywalk is not really for those

with a distrust in engineering.

In fact, it's an act of faith just to walk out there.

[Narrator]: This is the Grand Canyon Skywalk,

a big dream that almost pushed designers and engineers

over the edge.

So how did they build it?

Carved 6 million years ago by the mighty Colorado River,

the Grand Canyon is 277 miles long,

18 miles across at its widest,

and over a mile deep.

It's so large, it creates its own weather.

It's also home to the Hualapai tribe,

which owns over a million acres in northwest Arizona.

In 2003, they seize the opportunity

to share their culture

and raise funds for the local community

by creating somewhere special for visitors to enjoy

an unparalleled view of the canyon

at an important tribal landmark.

This spot, Eagle Point, is very sacred to our Hualapai people.

As you can see, there's a rock formation of Eagle Point.

Historically, what our forefathers and our medicine men

would do was come here to this specific spot

to pray for the wellness and well-being of our people.

And from here, the Eagle carries the prayers up to our creator.

[Narrator]: It is an extraordinary place

with an incredible view.

Simply perfect

and deserving of something completely out of the ordinary.

Together with a developer,

they hatch a ground-breaking plan to build a glass bridge

out over the canyon.

[Ruby]: We knew that the skywalk

was definitely the first in the world.

And we knew that it would put

Hualapai Grand Canyon West on the map.

[Corina]: Many grand designs are built simply to serve

the egos of billionaires.

But this bridge will bring real benefit to the local community.

[Narrator]: That's if they can actually build it,

because besides the brand-new cultural centre,

the design calls for a 150-foot steel bridge

that extends 70 feet out

before curving back in a huge horseshoe

and re-joining land.

It will appear unsupported,

hovering 4000 feet above the river below.

Its floor will be made from 46 panels of super-strong glass.

Taking the walkway will be like walking on air,

giving visitors a hair-raising view down into the valley below.

But designing is one thing.

Constructing is something else entirely.

[Hayley]: With a structure that's never been built before,

you're heading into the unknown. But with this structure,

the unknown happens to be at the edge of a cliff.

[Narrator]: This monumental task

falls to engineer Scott Klempke and his team.

A friend of a friend brought in a set of plans, a new project,

and said, uh, "Bridge over the Grand Canyon."

And we all thought it was an April Fool's joke.

And we started paging through it

and saw that it was literally a horseshoe bridge.

We started looking at it seriously

and thought it was something we could perform well on.

And we focused all of our attention to this project.

[Narrator]: The first challenge Scott and the team

have to overcome is creating foundations on land

that will be strong enough to support a 600-ton bridge

that only touches the ground at two points.

They turn to a piece of engineering magic

called a cantilever.

The skywalk is cantilever engineering

at its absolute purest.

Only its integral strength allows it to extend

that breath-taking 70 feet clear of the cliff edge.

But it's a heavy structure,

so it's gonna need some serious anchoring to its host rock.

[Narrator]: Thankfully, the site's geology

makes it perfect for the job.

[Ruby]: The rock within the area

was the strongest here at Grand Canyon West

to hold a building of this magnitude.

[Narrator]: In 2004, seven years of

planning and wondering is over.

It's time to bring in the equipment

and see if they can translate the design on paper

to reality in the rock.

Work begins on the foundations, which involves the engineers

drilling down 50 feet into the cliff face.

They then fill each hole with concrete

that's reinforced with tons of heavy-duty steel rods

known as rebar.

It will create a series of micropiles

anchoring the bridge to the cliff

and stopping it from toppling over the edge.

[Scott]: There's a cluster of micropiles...

Dozens, maybe, maybe 30 of them going down about 50 feet.

[Narrator]: The team then pours

a huge slab of reinforced concrete

which connects all the micropiles,

and onto which the sky bridge will eventually fix.

So that's a massive footing up top here, connecting all those.

[Narrator]: With the foundations in place,

the plan is to transport the 50-feet-long

steel sections of bridge

that have been fabricated in Salt Lake City

to the site by truck.

But the remoteness of the location

and rough road to get there

mean drivers will only come partway.

We had, you know, $100,000 rigs sitting there,

and they would stop, and they wanted to be offloaded.

And we had to put them on short-load trucks

and haul them in.

[Narrator]: One by one, the pieces of the bridge

are hauled to Eagle's Point.

The next challenge is figuring out exactly

how they're going to fix

the 600-ton bridge of steel together.

They decide that instead of building off the foundations

and out into thin air,

they're going to assemble the entire bridge

50 feet back from the cliff's edge.

It would be with cranes and cages and safety nets

and all kinds of things.

So much faster, simpler, cleaner.

Corrective work could be done easier

when it's on property here like this.

Pre-assembling the skywalk on solid ground

definitely have its benefits,

Construction workers are not exposed to the sheer drop

to the rocks below.

Plus, it's just way easier to inspect the structure

and, if needed, make any changes.

[Narrator]: Easier to build, yes.

But will it be easier to install?

[Hayley]: Then you've got this huge problem

of moving this structure into position.

I'm glad that's not my job.

[Narrator]: On the edge of the Grand Canyon,

a massive project is underway to build a sky bridge

which will float over the 4000-foot drop.

It's an enormous job and fraught with difficulty.

Now, having built it 50 feet back from the edge,

they have to work out how to move the 600-ton bridge

out over the canyon.

With no instruction manual,

they look to the past for inspiration.

The only thing I've ever heard it used for

is the Egyptians and the pyramids.

I have never seen anything like that.

Typically, you can use cranes in cantilever.

This is such a heavy structure

that we couldn't have enough crane work out here

to lift it up and set it in place.

[Narrator]: The plan is to lift the 600-ton bridge

with hydraulic jacks up onto multiple 2-inch rollers.

It's a system very similar to the way the ancient Egyptians

moved the sone blocks to build the pyramids.

As the bridge edges out over the drop,

huge steel plates placed onto the back

act as a counterweight to stop it tipping over.

Then, a winch cable will be attached

to the front of the bridge.

As the cable is tensioned,

the bridge will start to move towards its final resting place.

Get it wrong, that's going to be 4000 feet down

at the bottom of Grand Canyon.

It took two full days, very slowly,

to move the structure out in place.

We dropped it down onto these plates.

And over the course of that night,

we had welders out here

constantly welding the structure down.

[Narrator]: The bridge is in place.

But the challenges are far from over.

The next step is to create a walkway that's strong enough

to safely handle over 1 million visitors every year,

but clear enough to appear that when you look down,

you're walking on air.

[Hayley]: But this isn't ordinary glazing.

This is structural, laminated glass,

which can be incredibly strong.

To create the strength,

engineers layer the glass with different polymers and plastics

to make it less like the windows in your house

and more like bulletproof glass.

[Narrator]: Manufactured by a specialist company in Germany,

the glass is almost 3 inches thick

and made up of five separate layers bonded together.

On top, it has one final sheet of glass

that can be replaced if damaged

and a layer of plastic film to protect it from scratching.

Altogether it weighs in at over 80,000 pounds

and takes around three weeks to be lifted into place.

In September 2006, the bridge structure is in place.

But there is one last challenge the engineers have to overcome.

It's called positive feedback.

It happens where a small disturbance is amplified,

and it can result in disaster.

[Hayley]: Once a bridge moves a little,

everyone on it moves in sync to compensate,

and this is like adding fuel to the fire.

[Narrator]: Pedestrians unconsciously start moving

in time with the natural sway of the bridge.

And that amplifies it, making it worse and worse.

[Hayley]: The Millennium Bridge in London

had to close 2 days after it opened.

[Narrator]: Afraid the same thing could happen here,

the team tests out their secret weapon...

Kevin.

All right, so my colleague, Kevin,

is out bouncing on the bridge.

You can see the motions being picked up here.

So what I'm doing right now is trying to bounce

at the natural frequency of the bridge.

So it's kind of hard to tell when you're bouncing like this,

how it's moving, but if I stop for a second,

you can really feel it start to go.

[Narrator]: Inside the anchored base of the skywalk,

they've fitted a damper system.

Once it's properly calibrated,

this should reduce any bounce in the bridge.

[Andy]: So the graph is showing here how much amplitude

we're getting, acceleration in G's.

So we're hitting about 0.1 G's acceleration,

so a tenth the force of gravity.

[Narrator]: Now they turn on the mass dampeners

to see how much of an effect they have

on the bridge's movement.

[Andy]: So this is the big mass block, all this.

That's 1450 kilograms.

And then in behind here, you can see on the other side,

is there are viscous dampers.

It's like a shock absorber to draw the energy of the system.

[Narrator]: Like the shock absorbers in your car,

these should absorb the movement in the bridge

created by Kevin jumping.

In fact, they should enable the bridge to withstand 800 people,

each weighing 200 pounds,

and all jumping up and down at the same time.

[Andy]: Ultimately, we don't want them to know

this is even here.

They want to think the bridge is perfectly stable, smooth.

As long as that happens, we've done our job.

[music]

[Narrator]: In 2007, with the build finally complete,

the bridge opens to the public,

sharing the Hualapai tribe's rich cultural heritage

and an awe-inspiring view.

[Ruby]: The first time you're a little scared,

but definitely it's never the same.

Every time you walk on the skywalk, it's never the same.

I'm a little scared just cos it's a far way down.

[chatter]

It gives a bit of us as Hualapai

that the tourists and the visitors

will come and take with them

to feel that they shared that aha moment.

That's... that's a real [unintelligible].

[laughing]

[RoseMarie]: And they really took

that step of faith, of courage, and they got it here,

and kind of made you feel that backbone of, you know,

being Hualapai. It's a proud sense.

[Narrator]: This leg-shaking engineering marvel

gives tourists an unbeatable view

over one of the Seven Natural Wonders of the World,

while also helping the Hualapai tribe thrive.

This is truly a bridge like no other.

[music]

Now, if I were lucky enough to own

a large and priceless art collection,

my absolute number-one priority would be to find

the safest possible environment in which to have it stored

and displayed for future generations.

You know the kind of place...

A blizzard-prone Canadian forest,

middle of a major flood plain which,

when it's not under water, gets 15 feet of snow.

Now, that's where I'm building my gallery!

[Narrator]: In 2012, a wealthy entrepreneur

gives an internationally renowned firm of architects

a challenge.

He wants to create an extraordinary building

which will be as beautiful as the art it's designed to show.

It has to fit perfectly into the environment,

but be tough enough to survive whatever's thrown at it.

Which in this case, is going to be quite a lot,

given that the area is prone to...

raging blizzards...

severe flooding...

and serious earthquakes.

This building has to endure

one of the most inhospitable locations

in the whole of North America.

[Narrator]: Defying the challenges,

the architects and engineers

create an award-winning building that does exactly that.

This is the Audain Museum in Whistler.

So how did they built it?

[Narrator]: British Columbia.

Home to the Canadian Rocky Mountains...

stunning coastlines...

dense rainforests...

and to developer and philanthropist Michael Audain.

By 2012, Michael has spent over 60 years building up

an irreplaceable collection of art,

including one of the largest of First Nations masks

in the world.

[Michael]: We began to think, well, what?

What shall we do with it, with the collection?

Rather selfish just to keep it to ourselves.

I grew up in a town that lacked a public art gallery.

It's very important for me

that children have access to art museums.

It may change their lives forever.

[Narrator]: Michael decides that the answer

is to build a very special gallery

that will be open to the public.

The first challenge is choosing where.

What he was looking for was a site with trees.

And for him, it was very important that the context

of the museum be a forest like natural British Columbia

[Narrator]: In 2012, the team finds just the spot...

7000 feet above sea level,

in the middle of a forest in the town of Whistler.

It was a perfect site, as far as we're concerned.

[Narrator]: It's a small site in a clearing

in a pristine piece of forest.

But it's not the easiest place to build.

Michael's determined not to fell any trees.

And the clearing isn't big enough for the museum.

The problems don't end there.

Building on a river flood plain in Whistler?

Your building better be ready.

[John]: Outside of the protection of the dyke

that protects Whistler Village from

the really torrential floods that are possible

with Fitzsimmons Creek.

And building on this side of the dyke within the forest

was beautiful, but we were vulnerable to

very severe flooding.

[Narrator]: Add to that, it will also have to deal with

an annual snowfall of more than 15 feet.

And it will need to be earthquake proof.

But Michael has set his heart on the site.

So it falls to the architects and engineers

to create something that will work here

despite the challenges.

They come up with an awe-inspiring

two-storey structure

that will rise 65 feet from the forest floor.

To overcome the problems of the size of the plot

and create enough space,

it will bend around the mature trees.

The galleries and walkways will be lined wall to wall

with thousands of feet of triple-glazed windows

to make the most of its stunning location and keep out the cold,

while the rest of the building will be clad in local wood,

allowing it to merge seamlessly into the forest setting.

It will be lifted 16 feet off the ground on six legs

to protect it from flooding and earthquakes,

while a special pitched roof will protect the building

and art inside from the heavy snowfall.

[Ellie]: This is just a great example of a building

working with nature rather thn fighting against it.

Here the designers have adapted the building

so that it works with the environment

rather than just bulldozing right through it.

[Narrator]: Michael isn't immediately convinced.

It was a bit of a shock.

Initially, what they showed us looked to me like

an upside-down canoe on stilts.

[Narrator]: But after overcoming his initial surprise,

Michael signs off on the design,

and in 2013, construction begins.

The first challenge the engineers face

is to make sure the building can stand up to

any amount of flooding

The team will have to come up with something that not only

looks stunning, but can also withstand the worst excesses

of flooding that can come with climate change

in the years ahead.

[Narrator]: If the floods of the past are anything to go by,

this poses a real and present danger,

because they've swept through Fitzsimmons Creek,

near where the museum is being built, countless times.

In 1991, the most notorious was so powerful,

it destroyed homes and bridges in its path.

What they come up with seems remarkably simple,

but it's anything but that.

They're going to raise the building up on legs.

[John]: The entire building has been lifted

one floor above the ground,

which would allow the flood and, more importantly,

the debris that the flood carries through the site.

[Narrator]: They build six towering 16-foot legs,

on top of which the museum will sit,

lifting it above any floodwater.

These "piers" have three super-strength steel columns

running through them, making them strong enough

not only to withstand raging water,

but anything it's carrying along with it.

[Eric]: We had to design the structure inside the piers

for the impact of a car travelling

at 2 metres per second...

Or a log, whichever was the heavier.

[Narrator]: Although the team has overcome one problem,

they've made another potentially worse.

The area sits on two tectonic plates.

Their collision created the beautiful mountains

around Whistler, but it also means the region has a risk

of earthquakes.

Experts predict "the big one" could strike at any time.

[Eric]: We are in a moderate to high seismic zone.

So earthquakes definitely govern the design in this area,

especially for a building that is perched above the ground,

like this one.

[Narrator]: Usually, in earthquake regions,

buildings have built-in sections that buckle to absorb the shock.

But while they will prevent it from falling down,

a tremor can still damage the building's structural integrity.

So here, the engineering team turns to a cutting-edge solution

developed at the University of Toronto.

[Michael]: You can imagine a buckled brace

is causing a lot of damage to the structure,

and it's not really absorbing energy in an optimum manner.

[Narrator]: Michael's invention,

called a Scorpion Yielding Connector,

aims to solve both these issues.

[Michael]: When the brace is activated in tension

and compression during the earthquake,

then these fingers will yield and dissipate energy through

permanent bending in both directions

until the earthquake motion stops.

[Narrator]: Twelve Scorpion Yielding Connectors are placed

at each end of the building's support columns.

[Eric]: It has the ability to dissipate energy

even in a very severe and long earthquake,

which was the goal here.

[Narrator]: Mother Nature still has one more major challenge

for the designers to overcome.

Snow.

While it makes Whistler a mecca for thrill seekers,

it also has a pretty big impact on construction.

The snow loads here are about five times higher than they are

in Vancouver an hour and a half away.

It basically amounts to the equivalent of

3 metres of fairly dense snow.

[Narrator]: The weight of that much snow on a roof of this size

is phenomenal.

The traditional method of dealing with it

is to build a very strong roof structure.

But because the building is on legs,

the engineers want it to be as light as possible,

while the architects don't want to spoil

the look of the interior.

[Eric]: We were pretty keen to shed

as much of the snow and as we could

[Narrator]: Their first solution is to build the roof

at 50 degrees, a much steeper pitch than normal.

And they clad it in painted metal

to reduce friction and help the snow slide off.

We went from having to design for about 3 metres of snow

to designing for about a metre and a half of snow.

So that made a significant difference.

[music]

[Narrator]: After three years of construction,

the $50 million building is just about ready.

All it needs is the art,

including one of Xwalacktun's pieces.

[Xwalacktun]: It's the architecture.

It's the beauty.

I never saw anything like this before.

It all looks just great.

[Narrator]: A stunning piece of Xwalacktun's work

marks the entrance

and tells an ancient tale of floodwaters descending

from the nearby mountain.

[Xwalacktun]: We are on Salish territory

and the building stands on a floodplain.

So why not tell a Coast Salish story of a great flood?

[Narrator]: One that this museum would sit above,

quietly protecting the stunning British Columbian artwork

now housed inside.

I think this place is not about being loud.

I think it's about paying attention to the mountains.

That to me was like, wow,

that is so well thought out, and clever, and insightful.

[Narrator]: In 2016, the museum is about to open.

Michael Audain reflects on achieving his dream

that everyone, especially young people,

can enjoy his extraordinary collection.

[Michael]: I hope that their exposure to the building,

together with the art,

will give them an experience that they will remember.

[Narrator]: The Audain Museum has won numerous

architectural awards in Canada and across the globe.

It's an inspirational building,

honouring the region's past

and inspiring artists of the future.

Next, a gravity-defying library.

To Austria now, where one designer has used

a clever engineering trick to give the impression

whole sections of this spectacular building

are able to defy gravity and float above the sidewalk.

It's called the cantilever principle,

which maybe I could explain for you,

but I think I'm gonna let the experts do the heavy lifting.

[Mozart's Eine Kleine Nachtmusik plays]

[Narrator]: The city of Vienna in Austria

is famous the world over for its extravagantly ornamental

Baroque architecture dating back to the 17th century.

But in 2008, a university there needed a new home

and decided it was time to shake things up a bit.

If you have a reputation for being a little old school,

putting up a jaw-dropping building is a surefire way

to get noticed.

[Narrator]: To shape the city's future,

they turned to a legendary architect

with a reputation for designing the impossible

[Hayley]: The designers at Zaha Hadid

never do anything by halves.

But this building is on a completely different level.

[Narrator]: Zaha didn't disappoint,

dreaming up an incredible building

to sit at the heart of the new campus.

[Ellie]: It's just completely bonkers.

It looks like it's gonna fall down at any moment.

[Narrator]: A construction so radical,

some of the build team couldn't handle being on site.

[speaking German]

[Narrator]: Six storeys tall,

inside and out it leans over at a crazy 35-degree angle,

while its piece de resistance is an enormous reading room

that floats 85 feet above the sidewalk below.

This radical design is Vienna University's

Library and Learning Centre.

So how did they build it?

In 2007, Vienna University of Business and Economics

wants to up its game and make itself irresistible to students.

A site is chosen for a huge new 25-acre campus

that will be home to 20,000 students.

At its heart will be a flagship building.

Something to stop people in their tracks.

From the very beginning, we really want to show

that the most important we have at the university

are our students.

It was a very conscious decision to put

the Library and Learning Centre in the middle of the campus.

[Narrator]: Seeking an eye-catching design,

the university chooses a truly extraordinary architect,

her vision always pushing at the boundaries of engineering.

Zaha Hadid

Amongst her recent successes

are the Guangzhou Opera House in China

and the jaw-dropping Antwerp Port Authority extension.

What she imagines for Vienna

can only be described as the world's first extreme library.

One of seven new buildings on the campus,

the library will be the main showpiece...

Visually arresting, engineeringly heart-stopping.

To stop the building falling over,

the team plans to pour enormous foundations

using almost 100,000 cubic feet of reinforced concrete.

Then, they'll start work on the vertigo-inducing building

with its 35-degree walls

by creating a hugely strong system of pillars.

Next, nine prefabricated steel sections

will be craned into place

to form the external walls of the reading room

with its gravity-defying 80-foot overhang.

Finally, it will be clad in two contrasting colours,

defining the different blocks.

Unique and futuristic,

it will be like nothing the city has ever seen before.

We were very much impressed.

[Narrator]: In 2010, the engineers get to work

building the foundations.

It's an important stage in any project.

But here, it's absolutely crucial...

because not only do they have to resist the entire weight

of the building pushing down,

but also, the forces created by the sloping walls

trying to tear the foundations out of the ground.

[Corina]: In a normal building, weight is distributed evenly

across the foundations.

But this building is like an unbalanced seesaw,

pushing down on one side and pulling up on the other.

These opposing forces are going to put the foundations

under a serious amount of strain.

[Narrator]: To stop the building from tipping over,

the engineers devise a clever anchoring system

with a series of concrete piles set into the ground

that act like the roots of a tree.

[Narrator]: The rear of the foundations now act

like a counterweight, stopping the building toppling forward.

For even more stability

and to deal the downward forces of the rest of the building,

the engineers pour a rock-solid 12-foot-deep cement slab on top.

Now that the building is going nowhere,

the teams start to construct the steeply angled 35-degree walls.

The whole building is actually tilting forward.

The direction of tilt gives you

direction of the main entrance and plaza.

So, you know, always inside,

even if you've turned some corners,

it is a kind of like a compass.

It gives a directionality to all spaces.

[Narrator]: They may be dramatic and even inspired,

but creating these slopes isn't without its challenges.

The walls in traditional buildings are vertical

for a reason...

They help them stand up.

Without that, the engineers need to make sure

that this building won't simply collapse.

[Nehemaih]: With a building like this, weight is a huge issue.

You need to make sure that every single piece

counterbalances itself out weight-wise.

Every part has to be measured to absolute precision

to ensure that a weak link in the structure

does not risk making the building collapse in on itself.

[Narrator]: Next, can they pull it off?

[Narrator]: In Vienna, Austria, work is underway to build

a challenging new university building.

Using incredibly strong base plates made of steel,

42 pillars, each 18 inches thick and up to 120 feet long,

are bolted securely to the concrete slab.

These will support the 35-degree walls.

[Patrik]: Because these are quite intricate geometries,

you have to fit and end up in the right junctions and points...

Particular if you want to build fast,

where you build things simultaneously.

And the things are coming in,

if they don't fit, then you have a problem.

[Narrator]: The problems for the construction team

don't stop there.

The architects designed walls to lean in

at seemingly impossible angles,

and almost all are crucial to the strength of the building...

All of which proves too much for some of the team.

[Narrator]: With surgical precision,

the main building is taking shape.

But if the team found constructing

the 35-degree walls tough,

there's worse still to come.

In the spring of 2012,

they turn their attention to the two-storey section

that will sit on top,

with an 80-foot chunk hanging out over the sidewalk below.

It's made possible by using an amazing piece of engineering

called a cantilever.

Cantilevers are an incredible way of opening up spaces

and creating really interesting builds.

[Narrator]: A cantilever is a gravity-defying engineering tool

that at it its core is very simple.

It's an overhang, only supported on one side.

But instead of tipping over,

that force is transferred through the building

and into the foundations.

This can be done in many different ways.

But in Vienna, it starts with 200-foot-long girders

locked on to a series of leaning pillars.

[Narrator]: To make the structure even more rigid,

colossal prefabricated steel frames are craned in

to create the side walls.

When assembled and complete, each wall weighs 300 tons.

[Narrator]: It takes days, but the steel sections

weighing up to 50 tons are bolted into place.

The next challenge is to turn the cast concrete

and steel frames into the dramatic, distinctive boxes

the Zaha Hadid team imagines.

[Patrik]: The dark grey cladded elements are library elements.

And then the central student facilities,

they're expressed in light grey.

So they're tied together with some kind of ribbon move.

They're kind of interlocking systems...

Not fully separate, but always traceable.

[Narrator]: The team turns to a cladding system

made from a very special sort of material

called glass fibre reinforced concrete

Glass fibre concrete panels have become another useful weapon

in the construction armoury.

You can use these lightweight panels to clad any building

with any colour you desire for your build.

[Patrick]: This technique is used a lot,

and you can do very fine details.

We can also control the colour quite well.

[Narrator]: The system of adding dyes to the mix

during fabrication of the panels

means that you can choose exactly the colour you want.

And because each panel is made to measure,

they're very quick to put into place.

Not only are they easy to install, robust

and weather resistant,

but you don't need to paint them every few years.

[Narrator]: It takes three years to complete the build.

And in 2013, the university's astonishing new

Library and Learning Centre

turns on its lights and opens its doors.

Revealed is a futuristic, dynamic space

in which to teach, study or simply gaze.

The first moment in the morning when you enter it,

you have, wow.

[Edeltraud]: It's breath-taking.

It's a nice combination of aesthetic and engineering.

[Narrator]: Today those 35-degree walls

that once petrified construction crews

are a magnet for students from around the globe.

[Jose]: That was one of the most important things

that made me came here.

Like, wow, I will study in that building.

It's fun. It's something completely different.

[Narrator]: Up in the reading room, rock-solid engineering

keeps that serious cantilever holding everything up

over the campus...

broadening horizons for those inside.

I think for the brain, it's good that you have this view.

I'm very inspired by this building, yeah.

[Narrator]: The Vienna Learning Library is an architectural

and engineering wonder

that not only gives students a breath-taking place to study,

but also gives them the courage to question what's possible.

It's a monument to what hard work

and ingenuity can achieve.