Original subtitles

[awe-inspiring music]

[Jay] How do you create a trailblazing museum,

accessible to all, that evokes the Olympic spirit?

It's a place to house not only just the history,

but the dreams.

[Jay] How do you stop a mind-bending skyscraper

from falling down?

[Daniel] Well, there are many sleepless nights.

You know, how will this really work?

Can it really work?

[Jay] And how do you soundproof a new university building

from the roaring railroad above?

[Greg] The train measures at 100 decibels,

the equivalent to a jet engine at 300 meters.

[Jay] This is the age of the extraordinary.

[Dr. Agbedor] It's totally different

from anything around it.

It's like a visitor from another planet.

[dramatic music]

[Jay] Where ingenious engineers

have unleashed unchecked creativity.

Now their secrets are revealed

as we discover the amazing stories

of their construction.

[Dr. Mabry] It is simply mind-blowing.

I mean, how do you come up with an idea like that?

[dramatic choral music]

[Jay] To try and understand...

[dramatic music]

[Jay] ...how did they build that?

If you're gonna build a museum to celebrate

America's greatest-ever athletes,

the only way to do it would be with

some truly world-class architecture.

Now, this building may look silver on the outside,

but trust me, as a design,

this state-of-the-art Colorado Springs complex

wins gold medals all the way.

Every four years,

the Olympic spirit captures the world's imagination.

We watch, mesmerized,

as our fellow countrymen and women reach for glory.

But what would it look like

to honor their excellence with a building?

How could a steel and concrete structure

represent their grace and power?

Well, maybe like this.

It's a building that takes your breath away.

[dramatic music]

[Jay] A sleek, glistening jewel covered in 9,000 unique panels

that twists in an incredible athletic pose,

creating a one-of-a-kind museum.

[Holly] We were doing something that had never been done before.

So, it was really critical to think, "How is this done?"

[Jay] Building it involved

conquering extraordinary engineering challenges.

[Jeffrey] When I first saw this design,

I wondered, "How are we going to build this?"

[Jay] It took three years

and a cost of 91 million dollars.

[dramatic music]

[Jay] This is the US Olympic and Paralympic Museum.

So... how did they build it?

[music fading out]

[Jay] Colorado Springs.

[calm music]

[Jay] Set to the east of the majestic Rocky Mountains

some six thousand feet above sea level,

is known as Olympic City.

It's home to the US Olympic and Paralympic Committee

and their world-class training center.

In 2012, former Ohio governor Dick Celeste,

along with local community leaders,

decide to celebrate this by raising funds

to build America's first museum dedicated to

Olympians and Paralympians.

The building has to celebrate elite national sporting heroes.

Whatever you build, it had better be the best.

[Jay] To do that, they bring on Diller Scofidio + Renfro,

the architects responsible for High Line Park

and the shapeshifting shed in New York City.

[Elizabeth] Each project is an opportunity

to think about something in a new way,

to put something different on the surface of the earth.

[Benjamin] We needed to create galleries

that were suited to telling a series of stories, uh,

about Olympic athletes

that hadn't really been told in the same way before.

We genuinely felt like this is really something we could do

something different with,

that's gonna push us to a new place architecturally.

[calm music]

[Jay] At the heart of the idea is accessibility for all.

The intent was to really make sure it was thought through

from the ground up.

[John] A lot of times, we don't do that.

For compliancy, we look at,

"Oh my gosh, we forgot to do this ramp.

Oh my gosh, we forgot to do this."

Why, because we forgot to invite the people

that were going to use it into the conversation early.

[Tyler] This is a museum for everyone, but especially,

this is home for our US Olympians and Paralympians.

Making sure that every athlete,

but also any individual that comes in through these doors,

can have an equal experience

was always a part of the design process.

[Jay] More expensive and more complicated,

accessibility is too often an afterthought.

So, creating one of the world's most accessible museums

will be challenging,

especially as the team also wants it to embody

the vitality of the athletes it honors.

[Holly] It was really this idea of

trying to capture some of this energy of the athletes.

And we used the image of a discus thrower,

that, you know, spirals the shape out.

[Jay] By spring 2015,

the idea has solidified into a full design.

We had a central atrium

and a set of galleries, um, that, uh, uh,

circumnavigated this, uh, but always in perpetual motion.

So, there was nothing static. There were no regular floors.

[Jay] The design captures the Olympic spirit

in a beautiful, sleek, coiled sculpture of a museum.

To give every visitor the same experience

as they explore the collection,

there will be no stairs.

Instead, everyone will take an elevator to the top

and then descend via a spiraling series

of gently sloping ramps.

This twisting shape means they will not be able to use

standard floor plates.

Instead, they'll need to create a special frame to anchor it.

Outside, to evoke the movement of an athlete,

they'll need to find a way to wrap the building

in a sparkling skin of 9,000 unique aluminum panels.

The final challenge will be to connect it to a neighboring park

by designing a shimmering bridge

that they construct in just eight hours

over the top of active train tracks.

The result?

An astonishing building that celebrates

the incredible athletes who inspired it.

[contemplative music]

[dramatic music]

[Jay] In 2017, construction sets off

on a donated site next to a railyard.

[dramatic music]

[Jay] The easy part is creating deep pile foundations

going down about 40 feet to the bedrock below.

Then, the fun begins.

Most buildings are rectangular for a reason.

It makes it straightforward to channel the forces

created by their weight down into the foundations.

The more you mess with the shape,

the more difficult that becomes.

And here, with the whole design centering around

a continual spiral,

they're messing with it a lot.

Everybody's used to vertical walls and flat plates.

And when you do that,

the, everybody knows how to build that.

So, you add a complexity by adding even just a slant.

But then, we took a slant, and then we twist it.

[dramatic music]

[Jay] Left to its own devices,

this is a building that wants to fall over.

Stopping that from happening takes

some ingenious engineering.

[Holly] We have to start thinking about,

"What are the forces? How are we going to align that?

"How are we going to tie one member

"into the other member?

Uh, what, what's the smartest way of doing it?"

[Jay] The spiraling building

requires a complex system of steelwork

specially designed to handle irregular forces.

[Holly] There's a floor,

and the floor then has steel members in it

that then tie into that.

So, you can imagine... like a dancer,

where, you know, they're,

your partner's pulled back and leaning,

but you have an arm that supports you

and keeps you from falling over.

[calm music]

[Jay] Huge bespoke pieces of steel

act as the arm to hold up the twisted frame.

But they need a body to anchor them.

[Jeffrey] How we resolved that was

we took tension floors to brace the walls

back to large concrete cores.

[cool instrumental beat]

[Holly] We have four cores at the corners.

They're the four anchor points that then you can come off of,

um, and tie into.

[Jay] With the steel structure now secure,

the team turns its attention to engineering

the very complicated system of floors.

[instrumental beat fading out]

[Jay] Instead of this being a more conventional building

where the ramp is an addition,

the architects want all visitors to enjoy

an identical, stair-free journey through the galleries.

So, instead, the inside of the entire museum

gently spirals around a ramped route.

Because it ramps, it does mean that the entire building

steps down as you're going down.

So, you don't have a floor plate and then a floor plate.

[Jay] Normally, the floors are spaced at

nice, regular intervals,

which means once you've figured out the template,

you can just rinse and repeat.

But here, none are at the same height

across the entire floor.

In fact, if this building was more conventional,

it would've had three floors.

Instead, it will have 15 different levels

within a height of just 75 feet.

[Jeffrey] Uh, stepping on the floors

was very difficult.

It's because they change all the time,

and, uh, having to rethink,

"How do we support that floor level?"

was pretty complex.

[dramatic music]

[Jay] Holding up the floors

is gonna take a whole lot of engineering magic.

[Jay] It's spring 2018, and in Colorado Springs,

engineers are striving to find a way to support

the complex spiraling floors needed

to make the new US Olympic and Paralympic Museum

a world leader in accessibility.

[Jeffrey] We used almost every trick in the book

to help support this building.

We used columns to support it,

we had to use cantilevers,

uh, to support some of the floors.

Uh, we hung some floors from another floor above.

Sometimes we had to build something here,

and then, um, uh, build something below it.

[Jay] It takes ten months to complete the main structure.

Finally, though, they can move on to the next challenge.

[serious music]

[Jay] The architects wanna showcase

the building's muscular shape

by wrapping it in a sleek aluminum skin.

It was to create this feeling of movement and energy

across a façade.

[serious music]

[Jay] But figuring out the design

for an aluminum cladding needed

on a building with twists and curves

is far from easy.

I think that the skin was the biggest challenge

because at the time, it was at the cutting edge.

[Jay] It's only thanks to modern technology

that they managed to design

the intricate pattern of folded panels.

[Benjamin] It's really a 21st-century thing;

the ability to have digital environments

where you can map complex shapes.

[Jay] Now they have to build it.

The team constructs a frame from steel

which is strong enough to hold the skin in place,

but flexible enough for all the twists.

[dramatic music]

[Jay] Onto this, they attach diamond-shaped panels

made from aluminum,

9,000 of them, and every single one is unique.

[Holly] Each panel got a barcode on it

right away, from the very beginning,

so that each one is identified and had its address.

[Jay] Getting the panels into the correct position

is still a huge job.

Each has to be accurate to within an eighth of an inch.

[Jeffrey] As the contractor was building it,

they surveyed it,

they had drones scanning the building, uh,

just to verify that they were meeting the tolerances

and locations of all the parts and pieces correctly.

[dramatic music]

[Jay] By October 2019, the 9,000th panel is in place,

and the team is ready for its final challenge.

The city wants the museum to be linked to a neighboring park.

The problem is that means building a bridge over

14 rail freight lines that run alongside.

[Holly] One of the most critical things

is figuring out how to get this bridge in

and not disturb the active rail line.

[Elizabeth] It had to go 250 feet across,

and it had to clear the tracks, and we couldn't stop the trains.

[Jay] Elizabeth Diller and her team's solution

is to ship in the bridge already made.

The bridge was actually fabricated in Texas,

in six sections,

and then it was shipped to the other side of the tracks.

[Jay] Here, the sections are welded into

one complete structure.

Then, they launch

a carefully masterminded operation to install it,

working around the train schedule.

The really thrilling and exciting part

was to, uh, have these modular, robotic movers.

[dramatic music]

They had, like, someone guiding it from a remote.

[dramatic music]

[Jay] They know how they're going to move

the enormous bridge into place,

but now, the pressure is really on.

[dramatic music]

[Jay] They have just eight hours

before the next train rolls through.

[dramatic music]

[Holly] They brought the bridge into place

and rolled it across the tracks.

[serious music]

[Jay] The team can't relax until the final bolt is in place.

[serious music]

[Holly] And I think that they did it in

less than eight hours, actually.

It was really an amazing feat.

[awe-inspiring music]

[Jay] The incredible museum opens to the public

in July 2020,

the building inspiring its visitors

as much as the exhibits inside.

[awe-inspiring music]

[Elizabeth] This project is unique.

It liberated us from some of the conventions of

the way we've been thinking about structures.

[Jeffrey] This was a career-defining project.

Uh, just the iconic nature.

The architectural design of the building

is unlike anything that I've ever done before.

[Jay] With captioned and audio-described exhibits,

American Sign Language interpretation,

and, of course, the innovative ramp design,

it leads the way for museum accessibility.

[Michelle] This experience has been by far

the best that I've been able to have with a scooter,

as I was able to tour the entire building

with my family.

[Corey] It was really great.

There wasn't anywhere I couldn't go.

[Jay] A shimmering, twisting tribute

pays homage to the incredible athletes.

Team USA needs a place to house not only just the history,

but the dreams.

[Michelle] For athletes, I think the museum represents

that hard work, that grit, that determination

to make Team USA

and to celebrate the greatness of sport.

[Tyler] Being a Paralympian,

I couldn't think of anything else

that we could've done differently

to make this museum a welcoming home

for every athlete in the world.

This is one of the most exciting projects

I've worked on.

Capturing that Olympic and Paralympic spirit,

it's really amazing.

[inspiring music fading out]

[laidback percussion music]

When it comes to leaning towers that defy the laws of gravity,

Italy has quite a reputation to live up to.

So, when it came to building

a bespoke and head-turning new skyscraper

in the fashion capital of Milan,

you can bet your shirt that what they came up with

would seriously raise the bar in architectural high fashion.

[single piano note]

[Jay] Milan.

A city that leads the world in matters of style.

With buildings inspired by two and a half thousand years

of classic Italian architecture.

We are Milano, and we are stylish people.

[Jay] It's now home to a gravity-defying office tower.

Who says skyscrapers have to be straight?

[Jay] A dizzying glass-clad curve

nearly 600 feet tall.

Making a skyscraper bend

feels like you're breaking the laws of physics.

[dramatic music]

[Jay] It's an architectural marvel

that tested the limits of engineering.

[Mauro] From the beginning, we thought,

"Well, this is a little bit on the edge.

Maybe it's not possible."

[Jay] And tested the skills of its talented creators.

[Daniel] There were many sleepless nights.

How will this really work? Can it really work?

[Jay] This is Il Curvo.

So, how did they build it?

[single piano note]

[contemplative music]

[Jay] It's 2010, and in Milan,

the closure of an exhibition center

leaves an area of downtown in need of regeneration.

The developers hope to create a vibrant community

with workspaces, homes, museums, and parks.

[contemplative music]

[Aldo] This mixed use piece of land

became, uh, really, a part of

the urban regeneration of Milan.

[Jay] The heart of the master plan

of this new development

will be three dazzling office towers,

each designed by a super-star architect.

[contemplative music]

[Jay] First, Arata Isozaki builds Il Dritto,

"The Straight One".

Zaha Hadid follows up with Lo Storto,

"The Twisty One".

The third creation

by renowned Polish-American architect

Daniel Libeskin has a lot to live up to.

I thought, "Here is a chance to really extend

the vocabulary of urban design in this great city

and create something really, totally innovative."

[Jay] Libeskin takes inspiration

from Italy's classical building style

seen all over Milan.

[Daniel] The Italian architecture

is rich with curvatures.

So, this is a very Italian building.

[calm music]

[Jay] Libeskin's design is Il Curvo,

or "The Curved One".

A tower that looks like it wants to tip over.

So, the team's first challenge will be figuring out

what kind of foundations

can handle this epic battle with gravity.

[calm music]

[Jay] Then, they will need to engineer

a special concrete core

that won't buckle under the uneven forces

caused by the building's shape.

[calm music]

[Jay] To create its curve,

they'll need 28 different floor plates.

[calm music]

[Jay] And they'll need to work out how to deal with

the different forces each of these floors will create.

Bespoke glass panels will be designed to cover

each bending floor.

[calm music]

[Jay] And on top, they will need to somehow create

the building's final masterpiece:

a 600-ton, self-supporting glass roof.

[calm music fading out]

[Jay] It's 2015.

Two towers are nearly finished when work begins on Il Curvo.

For the building to stand up and stay put,

the first thing the team needs to get right

are the foundations.

The big issue for foundation is that

the tower should not sink over time.

It should just stay there and absorb all the stresses,

and put that into the soil, into the ground.

So, we will not have a Pisa Tower effect.

The Tower of Pisa leans because the soil underneath

is different on both sides.

The thing is, the foundations don't take that into account.

They can't risk that happening here.

[machines whirring]

[Jay] The foundation system they choose

is a wide, stable raft of concrete that sits on piles.

[Mauro] It's a 2.5-meter-thickness raft,

which is one of the biggest casting operations

doing without, uh, interruption, in, uh, in Italy.

[Jay] It takes 36 hours and a steady stream of trucks

pouring 200,000 tons of concrete.

But now, they have a massive foundation block

that isn't going anywhere.

[serious music]

[Jay] The work below ground was easy

compared to what they have to figure out next.

The most important point is also the most obvious one:

how do you stop a curved building

from falling over?

[Jay] As any fitness instructor will tell you,

the secret to great stability is having a solid core.

In a normal building, that's pretty straightforward.

With a symmetrical tower, the core is right in the middle.

So, pressure is applied equally downwards.

But Il Curvo's shape means

the core is being pulled in all directions.

[Jay] This is because to create the curve,

the floor plates sit in

slightly different positions to one another.

[contemplative music]

[Jay] As they go up the building,

some of the floors have more of their area on the one side,

some on the other.

[Daniel] Each floor is in a different position in space.

There's no floor exactly above you,

and no floor exactly below you.

[Jay] But this means the forces

each floor puts on the core are different

and risk it cracking under the strain.

Part of the solution lies in

building in special tension cables

into the concrete.

Those cables are pulled and then blocked into the concrete,

so we have a big traction in the cables

that compress the concrete, so the whole shaft,

the whole core is always under compression

so it doesn't lose, uh, stiffness.

[Jay] On its own,

reinforcing the core won't be enough.

The team also needs to add extra columns on each level.

In a typical rectangular building,

engineers could use one design throughout.

[serious music]

[Jay] But not here.

So, unevenly stacked floors mean the pressures on

each of these columns is different.

Basically, there's no one-size-fits-all solution.

[Jay] Each column must be individually designed

and fabricated to deal with

the precise load it needs to carry.

It takes a whole lotta math

and even more concrete and steel.

But Il Curvo's structure can now quickly take shape.

[contemplative music]

[Jay] The next job is to get the glazing right.

And some similarly bendy buildings

have shown what happens when it goes wrong.

Palazzo Lombardia in Milan

and 20 Fenchurch Street,

AKA the Walkie Talkie, in London, England

were both built with curving glass.

When the sun's rays first hit these new towers,

their smooth curves caused an unexpected problem.

[serious music]

Like a magnifying glass,

these buildings focused the sun's rays

all into one place,

damaging nearby cars and buildings.

[serious music]

[Daniel] How to make sure that

the reflectivity of the building,

particularly on the concave side,

does not impact people and heat on the outside.

Because, you know, a curvature takes the light and focuses it.

[serious music]

[Jay] How will they create a glittering, curved façade

without frying the streets below?

[Jay] In Milan, the team behind building

a new curving skyscraper

need to make sure its glass façade

won't focus the sun on people below,

like ants under a magnifying glass.

It was a real challenge

because the façades are

very different from each other.

In fact, the southern elevation is concave,

while the northern part is convex.

[Jay] The team's ingenious, but simple solution

is to make the concave side

from a series of stepped vertical panes.

It will give the illusion of a curve from a distance,

but break up the reflected light.

Each level steps in, in, in and out as it goes,

so that the reflectivity is parallel to the ground,

never focusing into the ground.

[serious music]

[Jay] Passing pedestrians will now be safe.

But it does mean all 2400 glass cells

have to be individually made.

It took a long time.

In one day, it was possible to create

about 14, 15 cells.

No more given the high complexity.

[Jay] Once on site,

fitting these 15 foot by 5 foot panes

is a high-wire job.

Especially higher up,

where the building curves back onto itself

with no supporting structure below.

It takes eight painstaking months,

but finally, they reach the top.

[Gian Luca] The installation of the final glass cell

was a very emotional moment.

This was where we could relax.

We'd achieved our first goal.

[Jay] As the tower nears completion,

the team faces one final challenge.

Normally the roof of a skyscraper

is used for practical purposes,

and Il Curvo is no different.

Many of the services of the building

are up in that space.

[Jay] The problem is that maintenance cranes,

ventilation, and water recovery systems

are hardly glamorous.

And Daniel Libeskin doesn't want his curvy masterpiece

ruined by ugly equipment.

[Daniel] The top of any building is incredibly important.

From the Empire State to any building,

you look at the top--

what does it look like in the, in the, in the sky?

[Jay] Libeskin's idea is to conceal all the machinery

inside a glass roof over a hundred feet tall;

a beautiful idea.

To pull it off 450 feet in the air,

the team invents a 600-ton steel and glass structure

that's stable during each step of construction without support.

The design in, in construction is like a very big puzzle.

It's uh, uh, very crowded steel structures.

We work with, uh, millimeters between each part.

[Jay] When the steel framework is finally in place,

it stands 130 feet tall

with not a ventilation shaft in sight.

[Marco] For me, it's one of the best place of the tower,

because it, uh, this,

this factor is, uh, is, uh, fantastic.

[percussion music fading out]

[Jay] It's 2020, and Il Curvo is finally finished,

completing the striking trilogy of towers

that redefines Milan's skyline.

Completing this project was very satisfying for me.

And every time I see it,

it fills me with great happiness.

[Jay] The team has engineered and built something

that shouldn't have been possible.

[Mauro] I personally was skeptical

about the shapes of these buildings

when I saw the proposal at the beginning.

Now, I'm totally convinced, and the city is, too.

But it's an important tower,

it's one of the iconic building in Milano,

and, and this is my office.

[Jay] In the process,

they've created a new icon of Italian architecture.

[Corina] For hundreds of years,

Italy's been famous for having one leaning building,

and now it has two.

[Daniel] If you're an architect, never start by thinking,

"Can it be built?"

Because the answer will be always no.

Start with something that you have no idea if it can be built.

[inspiring music]

[laidback percussion music]

Next stop, Chicago,

where a new student center was needed for

the Illinois Institute of Technology.

Now, not only would the building have to function

beneath a noisy train line,

it also would have to complement the existing 1940s campus

designed by Bauhaus School legend

Ludwig Mies van der Rohe.

No pressure, guys.

[contemplative music]

[Jay] Chicago, Illinois is America's railroad capital.

[contemplative music]

[Jay] From its long-distance lines

fanning out from Union Station

to the 122 miles of

the rapid transit system's elevated tracks,

the railroads have had a big impact on the city.

[contemplative music]

[Jay] On the South Side,

the Illinois Institute of Technology

was cut in half by an elevated rail line

until a brilliant architect and clever engineers

came up with an astonishing solution.

[awe-inspiring music]

[Jay] This is the McCormick Tribune Campus Center,

a brand-new building squeezed under the railroad tracks,

which brought the university back to life.

What an amazing structure.

[Jay] Engineers had to silence the roar from overhead.

The train measures at a hundred decibels.

It's the equivalent to a jet engine at 300 meters.

[Jay] It had to be built without interfering with

the trains running through it.

There's a train every eight minutes.

Just imagine working around that.

[Jay] So, how did they build it?

[single piano note]

[contemplative piano music]

[Jay] Located in Chicago's South Side,

the Illinois Institute of Technology

is a university with a proud history.

The original campus was designed in the 1940s and '50s

by one of the world's most important architects,

Ludwig Mies van der Rohe,

one of the founding fathers of modernist design.

Mies van der Rohe's design philosophy

was one of less is more.

He wanted to make the campus a statement of the modern era--

that is, logical and linear architecture

for a technological society.

[Jay] With 20 buildings all designed around

an orderly 24-foot grid system

in Mies's signature stripped-back style,

in its day,

the university's breathtaking simplicity

was revered.

But by the late 1990s,

it's being seen through different eyes.

[Donna] This campus was considered one of

the least beautiful campuses in America,

and there may have even been a survey that said that.

[Jay] The campus just isn't suited for modern student life,

and there's a major problem in sorting that out.

Campus is split in half by an elevated rail line

that runs throughout Chicago.

[Dr. Mabry] It means the original plan,

the area directly below was to be landscaped gardens.

But the idea falls by the wayside,

and the land evolved into an unsightly parking lot.

[Jay] On the one side, there are the student dorms.

On the other, the classrooms.

For the students, whichever side of the train tracks

that you were on was the wrong one.

[Jay] It's a problem that's becoming impossible to ignore.

[Donna] As it runs through campus,

it creates a lot of noise and vibration.

When people were outside, if a train went by,

they had to stop conversation and wait

until they could be, uh, heard again.

[Jay] So, in 1998,

the university decides to do something about it.

[Donna] They wanted a significant building.

Not one that just solved the problem,

but one that really talked about the future of architecture

in the same way that Mies had

when he put his buildings here on campus.

[serious music]

[Jay] They launch a worldwide competition

to design a soundproof, five-story building

to go beside the tracks,

near to one of the historic Mies van der Rohe buildings.

But Dutch architect Rem Koolhas disregards the brief.

Koolhaas suggested not a five-story building,

but instead a one-story building

that wiggle itself underneath the train track.

No one had seen a scheme like this before.

So, it felt quite adventurous.

[Jay] Koolhaas's design wins the competition,

and will send the team who have to build it

into uncharted territory.

[orchestral music]

[Jay] First, they'll have to find a way to safely support

the hundred-year-old railroad overhead.

Then, they'll need to design a bespoke acoustic structure

capable of muffling the noise of the trains,

which can be built while they're still running.

To unite the campus

and give the students the facilities they need,

they'll then have to squeeze

an entire 110,000-square-foot building

beneath the elevated line.

[inspiring music]

[Jay] To complete Koolhaas's vision,

the building must be linked to one of the original

Ludwig Mies van der Rohe structures

without detracting from its historic features.

[serious music]

[Jay] In late 2000, work begins.

[serious music]

[Jay] And the first problem engineers face

is the railroad that runs over the site of the new building.

[serious music]

[Greg] The Chicago fire department

was concerned about a fire on the tracks

now that there's a building under it and around it.

[serious music]

[Jay] In the event of a fire,

the old iron railway structure could buckle,

even collapse quicker than more modern materials...

...with a building full of students underneath.

The solution is to replace the iron columns

with huge, highly engineered concrete piers

sunk 64 feet down into the bedrock.

[dramatic music]

[Greg] We got something like four hours of

fire separation between the tracks and the building,

with the thought being that within four hours,

we should be able to completely evacuate the building

in the event of an emergency.

[Jay] It takes six months to create the 18 new supports,

but by the summer of 2021,

they're ready to move on to their next challenge:

finding a way to deaden

the deafening sound of the trains

roaring overhead at 55 miles per hour.

[Greg] The train measures at 100 decibels.

Normal conversation can continue at 70 decibels.

[laidback percussion music]

[Jay] So, how will they turn down the volume?

[Jay] In Chicago, Illinois,

a new student campus center is being built directly beneath

the elevated tracks of one of the city's train lines.

To reduce the deafening sound of trains going overhead,

their bold plan is to wrap the tracks

in a specially designed stainless steel acoustic tube.

For it to work,

the engineers first need to minimize the vibrations.

They do that by constructing

a completely independent framework

to support the tunnel.

It has no structural contact with the track or the building.

By not having the structure of the building,

the tube, and the CTA tracks touch one another,

we were not transferring the vibration of the tracks

into the tube or into the building.

[Jay] It takes several months to build the supports

in the bottom half of the tube.

But simply wrapping the trains in steel

and preventing vibrations won't be enough.

The other key principle that acoustic engineers look for

is sound insulation.

The louder the sound,

the more mass you need between the source

and the people you're trying to protect.

[dramatic music]

[Jay] Deafening the 100-decibel trains

will take an enormous 9,200 cubic yards of concrete,

laid in an eight-inch-thick slab.

The concrete in the underbelly was really the, the mass,

the separation to control the sound and the noise.

[electronic music]

[Jay] With the concrete poured, the tube is almost complete.

All that remains is to build the top half.

On most construction sites,

this would be fairly straightforward.

But here, it's anything but.

[Donna] The Chicago Transit Authority

has many regulations and strictures

for how construction can happen.

And they didn't want

train service to be interrupted at all.

[Jay] The upper part of the tube is made up of

23 individual steel arches,

which need to be craned in place over the live tracks.

[Greg] That's when we really had to be careful

in engaging with the trains.

[Jay] It takes meticulous planning and preparation

before they're ready to start.

[contemplative music]

[Greg] We chose a time when

the fewest number of trains were running,

and that happened to be midnight on a Friday night.

The cranes were set up,

they had the structural steel hoops.

[Jay] The team works quickly during gaps between trains,

dropping their tools each time one needs to pass.

[Greg] The trains would slow down to almost a crawl,

you know, just for safety concerns.

[contemplative music]

And they sat the first one in place.

Couldn't have worked out any better.

There were kind of cheers on the site.

[Jay] Three days later,

the freestanding tube is complete.

[hopeful music]

[serious music]

[Jay] With the difficult part of the build out of the way,

work starts on the new campus building,

which will run under the tracks.

It's been designed to neatly connect to

the original commons building,

which has its support columns arranged

on the same 24-foot grid.

[dramatic music]

[Jay] But some parts of the architecture community

fear that once complete,

the new building will overwhelm the old.

[dramatic music]

[Donna] There were meetings to try to effect a way

in which the design could sit happily

with this existing Mies building.

[Jay] Architect Rem Koolhaas finds a simple,

yet ingenious way to connect the buildings

without spoiling the view of the commons.

The compromised solution was that the glass type used in

the last bay of the new elevation

would be a super clear glass.

And that would allow you to see that this existing building

by Mies was actually, uh, something to be understood

from all sides.

[Jay] And Koolhaas has one final flourish

to honor Mies's work.

We excavated down and exposed a portion of the foundation

of the existing commons building.

So, as you move around inside the campus center,

you see this historic Mies van der Rohe building

that appears to be kind of lifted up on a pedestal.

[gentle string music]

[Jay] In September 2003,

after five years of planning, designing, and construction,

the campus center opens its doors to the students.

The building's corridors track the routes they once took

as the traveled under the elevated train

between dorms and classes.

But now, instead of dashing through a parking lot,

they can linger in spaces designed for hanging out.

[Male Student] Personally, I love it.

It's the crossroads where everybody comes together,

and it's just where a lot of

the special moments during college happen.

[Male Student] This is where all the students go for food

and sometimes studying.

And if we wait long enough, sometimes a train will pass,

and the students get really excited from that.

[calm string music]

[Jay] Thanks to the ingenious science

behind the acoustic tube,

with noise levels well below the target 70 decibels,

even the quietest of activities is now possible here.

[Female Student] We're in our student-run radio station

on campus.

All of the recording and stuff happens right here.

You can definitely hear the train when it goes by,

just sort of, like, a little rumble.

It's not anything that is distracting.

It just sort of adds a little character to the shows.

[calm string music]

[Jay] Now the design students have a new masterpiece

to inspire them.

As an architecture student, this is the perfect campus.

You've got Mies van der Rohe

really showing off new Bauhaus style

to the full extent,

and then you've got Rem Koolhaas twisting it a bit.

[Greg] Mies's quote was,

"I leave my buildings to you

to do with them what you'd like."

So, I think Mies would've been very pleased

with the state of the campus now.

[calm string music fading out]

[dramatic orchestral music]

[dramatic choral music]

♪ MTV ♪