Original subtitles

it reinvigorates a forgotten neighborhood?

We had to build this ceiling structure

with two crews at once, and then there was this moment

where they had to meet in the middle.

We weren’t sure was it gonna actually meet.

How do you build a 1,500-foot bridge

that supports itself almost entirely from above?

There were many sleepless nights.

This tensegrity bridge, it had never been attempted

anywhere in the world.

And how do you build a colossal skyscraper

in record time with an engineering technique

never used like this before?

Everyone came with this mentality,

we don’t know how we’re gonna get it done,

but we’ll figure it out.

Welcome to a world where anything is possible.

The space where innovation and creativity collide.

This isn’t just impressive, it’s revolutionary.

Where the only limit is human imagination.

This wasn’t just ambitious, it was audacious.

No one had ever attempted anything like it.

Unpacking the miracles and mysteries of construction.

Sometimes buildings can change the world.

And this is one of them.

To ask...

How Did They Build That?

You know that phrase

"So many books, so little time"?

Well, when an inspiring new library was proposed

for Calgary, Canada,

it was more a case of "So many books

"and a totally unsuitable site for a building

big enough to keep them all in."

Of course, if there’s one thing great architects love,

it’s an "impossible" project.

And the building they produced

is seriously worth shouting about--

even inside a library.

Shh!

Oh, sorry. Shh, shh. Sorry. Sorry.

At the turn of the 21st century,

Calgary, Alberta is one of Canada’s

fastest-growing cities

thanks to its thriving energy and financial sectors.

But Calgary’s East Village neighborhood

has been struggling to keep up since the 1940s.

It hadn’t really been taken care of.

There was a lot of buildings that were in disrepair.

Things only got worse in the 1980s

with the introduction of the new light rail train.

When the light rail transit line went in,

it was literally a physical barrier.

It cut off access between

the west of the city and the East Village.

The city decides it needs

to reinvigorate this part of town.

And in 2007, plans are drawn up to redevelop it.

Our challenge was to change perceptions of the district.

At the heart of it will be a brand new library

built on a plot of land

with the train tracks running right through it.

The new Central Library project became an opportunity

to reconnect these two parts of the city.

They settle on a design from a local company, Dialog,

and global firm, Snohetta, a company with a reputation

for complicated buildings.

So the difficult site doesn’t daunt them.

In fact, it inspires them.

We realized that the library could be formed

around the curve of the train line

so that the library could lift itself up

over the train line

and then create this prow, like a boat,

towards the center of the city

and connect the east side and the west side of the town

where it had previously been cut off.

I think that at the start,

we knew that we were on to something

that had the potential to be great.

The architects’ goal is for the building to be

much more than a simple library.

Sitting on top of the tracks,

it will bridge the two parts of the city.

First, they will have to find a way

to safely enclose the 600-volt electric cable

that powers the trains

and figure out how to keep the noise from

disturbing the readers.

Next, they need to find a way to support the elevated building

and the 180 tons of books that will be inside.

To join the two sides of the tracks,

there will be a passageway under the library.

Its complex curving design will mean

bending thousands of pieces of wood,

each to the exact right shape.

But they will need to do all of this

without disrupting the train service

running through the site.

If they can pull it off,

they will have successfully reunited

Calgary’s downtown with the East Village.

So this is a project

that actually was gonna be a challenge

from day one

all the way, actually, to the end of the project.

The team arrives on site in spring 2014.

Their first problem, working out how to build over

one of the busiest rail lines in North America,

which carries 90 million passengers a year.

When we started looking at the plans and visiting the site,

the reality set in as to how close

the active railway corridor was to the geometry of the building.

It will require both a feat of engineering

and steady nerves

as the team works to carefully enclose

the active train tracks

in a concrete box almost 500 feet long.

We’re doing all this work,

which is very complicated anyway.

And in the middle of it all, you have a train passing

and the passengers are waving at you.

And it’s like, what is happening?

Now they need to install the roof.

It was directly over top, you know,

just a few inches above

the contact wire that has thousands of volts.

If you even get close,

there’s a chance of getting electrified.

You don’t even have to touch it.

Turning the power off costs US $100,000 a day.

So the transit company will only allow one 48-hour shutdown.

The only way they stood a chance of getting the roof in

quickly enough was to make it off-site.

Huge concrete panels were prefabricated,

then lifted into place like a giant puzzle.

At midnight on August 22nd, 2015,

the power is turned off.

And then the 24 hours, it was go, go, go.

All these pieces had to fit perfectly

and had to be erected seamlessly.

All 60 of them, and each one being unique.

It’s a race against the clock.

There was a lot of anxiety.

A lot of anxiety with that.

Finally, with eight hours to spare,

the last panel slides into place.

Once that roof was placed, there was a huge moment,

sigh of relief.

With the light rail enclosed,

in September 2015,

the team can start work on the library itself.

But finding a structural system to hold it up

is a massive challenge.

Engineers love columns.

Plenty of vertical supports

that direct forces down into the foundations.

The trouble here was

the architects wanted a grand, open entrance

without a single column in sight.

The books alone will weigh an incredible 180 tons.

How do we take all of these enormous loads

and transfer them all the way down the building?

So the solution for that

was to design very large structural steel trusses.

The huge trusses were built

from interlocking triangles,

which are nature’s strongest shape.

They don’t just hold the weight, they distribute it perfectly,

making them nearly unbreakable.

80 enormous steel beams,

the largest 170 feet long and weighing 30 tons--

the same as a humpback whale--

are welded together

to form the five enormous trusses.

There’s weeks of welding.

Weeks and weeks of welding.

Then, as the trusses are being put together,

they discover a massive problem.

There was a couple members where the steel,

after the fabrication, had a series of hairline cracks.

Even the tiniest fault in those massive steel trusses

could cause the whole building to collapse.

They had to be rock solid.

No one really knew what was causing those cracks.

The team realizes the issue is

in how the steel is being made.

Steel isn’t perfect.

Every single piece has tiny flaws.

If it cools too fast,

these flaws turn into stress points.

And stress points turn into cracks.

Those can lead to big trouble.

To overcome it, they start again,

this time with a slower cooling process.

It solved the challenge. We didn’t see it happen again.

And by November 2016,

the fifth and final truss is in place.

The team can move on to the next challenge,

making sure the noise caused

by vibrations from the passing trains

doesn’t disrupt the library.

Instead of the concrete being

rigidly connected to the pile foundation,

you basically break that connection.

And it’s a series of layers of rubber pads and steel

that help dissipate that rumble from the tracks.

Over the next six months,

they build the main structure

before wrapping it in almost 500 crystalline panels

to create the glimmering facade.

Finally, the building’s beauty is starting to shine through.

When you’re inside,

walking along the corridors alongside that facade,

which is getting all of these reflections,

it’s like being in a kaleidoscope.

The next major challenge will be

creating the wood-covered passageway,

which was inspired by the weather

over the Rocky Mountains.

When two pressure systems meet, they create this arched cloud,

this vast arch,

and it can stretch 100 miles across the horizon.

It’s called a Chinook cloud.

To create this swooping overhead entrance,

they decide to use locally sourced

Western red cedar timber--

beautiful, durable, and sustainable,

but not very pliable.

Once you bend a piece of wood to a certain point,

I mean, eventually it cracks, it splits, it breaks.

In Calgary, Alberta, Canada,

the team behind an incredible library

built on top of the city’s light rail train

are creating a swooping entrance

made from local red cedar timber.

But how do you bend a huge wooden arch

without breaking it?

You reboot technology used by the ancient Egyptians.

Steam bending works by placing wood into a sealed box

and filling it with steam.

The heat and the moisture soften the wood just enough

to bend it into shape--

but only for a short, critical window.

It created this incredible,

intense moments in manufacturing

where it would be, okay, go, guys, the steam box is ready.

We’re taking the battens out of the box.

We gotta run over to the jigs,

push them down before they kind of harden.

Twisting and bending the arch in two directions

is incredibly complicated

and needs some 21st century technology

to help pull it off.

We created a highly accurate three-dimensional computer model

of the entire ceiling structure to be able to know exactly where

each piece of timber should go.

And we used incredibly complex software algorithms

to actually model the geometry of each individual wood batten.

Then, the 21,000 square feet

of curving cedar needs to be fitted quickly.

Due to the schedule, we had to build

this ceiling structure with two crews at once.

So we started from the ground, as you can imagine,

with one crew, and we started way over here

at the other end from the other crew.

And then there was this moment

where they had to meet in the middle.

We weren’t sure, was it gonna actually meet?

Four months after starting,

they’re about to find out.

I still remember our site supervisor calling me

and he was like, it fit!

Just an incredible moment, right?

After four and a half years of construction,

on November 1st, 2018,

Calgary’s incredible new Central Library

opens its doors to the public.

That opening day was so amazing.

To see everyone else see

what I’d seen over the last five years

was very emotional.

When we first came here,

we were like, wow, this is amazing.

Definitely we have to come back.

I walked in here and it was like,

wow, I couldn’t believe what I was seeing.

It didn’t look like a library to me.

This is breathtaking.

But this is more than a library.

Its extraordinary timber-framed walkway sits above the railway,

healing the divide between the East Village

and the rest of downtown.

With the addition of the library,

East Village has really gone from a part of our downtown

to being a part of Calgary that shouldn’t be missed.

A temple to reading unlike any other on the planet.

It’s just such an incredible building

and an incredible library.

I think Calgary has absolutely redefined

what a library can be, and I would argue should be.

When architects were tasked to build a new skyscraper

on a super tight deadline,

they turned to a never before used

construction concept to get it done--

SpeedCore.

And while any new engineering technique

comes with a degree of risk,

the people of Seattle were less concerned about

the building going up

as they were about the 50-year-old

architectural masterpiece next door crashing down.

Seattle is the largest metropolis

in the Pacific Northwest,

with a stunning skyline to prove it.

And in 2014, there are plans for

a colossal new skyscraper to join it.

The build site is on a block that is already home

to the beloved Rainier Tower,

a skyscraper whose chewed bottom has earned it a nickname.

Locals call it the Beaver Building,

and it was designed by Seattle-born architect

Minoru Yamasaki,

who’s best known for New York’s Twin Towers.

So it’s pretty special.

Not surprisingly, the space comes with

some seriously tight building restrictions.

Any development plan for

the remaining three quarters of the block

should not obstruct the views

in the original Rainier Tower.

That, though, isn’t enough

to stop Seattle architects NBBJ

from coming up with a radical plan for

58 stories of mixed-use space

Retail at the bottom, offices in the middle,

and then 18 floors of residential units at the top.

Building it will come with a whole set of challenges.

Because first, they will have to dig down 100 feet

to create the foundation without bringing down

its 50-year-old neighbor in the process.

Then they must stop the soil around the foundation

from caving in.

A traditional concrete core is gonna be too slow

and too expensive.

So they need to find a revolutionary new way

of holding the building up.

And when they’ve done all that, the finished tower

needs to complement the Beaver Building

and not get in the way of its views.

Definitely probably one of the more complicate projects

that I have been part of and our team has been part of.

On May 8th, 2014, the team wins the contract.

The search for an engineer is on.

Luckily, they don’t have to look far.

The building was literally right outside of

my personal office window, 60 feet away.

Having worked in the Beaver Building since the 90s,

Ron knows the site, warts and all.

Of the many challenges on this building,

one that we faced straight away, was

how are we going to make the below-grade levels--

the basements, if you will.

The new Rainier Square tower

will have a six-story parking garage, all underground.

And that means digging a very big hole.

But still very daunting where you’re going to dig

a 100-foot hole immediately adjacent to

an occupied 40-story building.

So this was kind of challenge number one.

In Seattle, work starts excavating for the foundation

of an enormous 58-story tower,

which will sit feet away

from one of the city’s most iconic buildings.

It’s nothing if not challenging.

How do you do that while not putting in peril

the existing 40-story building?

Its extraordinary shape

makes it all the more difficult.

What’s really unique about this particular tower

is that the base of the tower is a pedestal.

This incredibly small footprint

means it’s putting even more pressure

on the soil beneath.

To stop the excavations from bringing it down,

the team must hold the soil under the original tower

in place by building a huge wall.

The best analogy I can offer you,

if you can imagine a dam

that’s holding back not water, but dirt.

And that dirt happens to have

a 40-story building on top of it.

Perhaps, not surprisingly,

this wall needs to be pretty special.

The actual dam, or the wall, that we built

is a secant pile wall.

A secant pile wall is a set of overlapping concrete columns.

Normally, a secant pile wall

might be 24 to 30-inch diameter holes.

In this case, we had holes that were 5 feet diameters.

With the wall in place, work progresses very carefully.

There was a very extensive monitoring system set up

to determine if the building itself

was moving in any way that was of any concern.

It moved, but it moved within expectations.

It all performed as it was intended to perform.

Their next challenge

is going to be building the tower.

Around the world, many, many tall buildings

have been designed and constructed using what is

a reinforced concrete core.

It’s a column that runs through

the center of the tower

and usually houses the elevators and stairwells.

It’s what gives big skyscrapers their strength.

It’s a tried and tested method,

but here, there’s a pretty big problem.

We made an evaluation of the cost and the time required

to build that design.

And the conclusion was that

it cost too much and it took too long.

And that was our cue

to introduce this idea of SpeedCore.

Developed in the 1990s in the United Kingdom,

the SpeedCore building system was largely unknown.

At the time, I’d never heard of it.

But it had been used in nuclear facilities before

for blast resistance, but never in a high rise.

The concept of SpeedCore is

to prefabricate steel modules

and then stacked up one on top of another,

kind of like Lego blocks.

Then to add to its strength and stiffness,

fill them full of concrete.

Using it here to create the tower’s strength

will be revolutionary.

What’s amazing about the SpeedCore is you’re able

to build the core and the floors at the same time,

which is where you’re saving a huge amount of time.

In theory, building this way

will make it cheaper and quicker.

We’re able to go back to our client and report,

lo and behold, we think we can save 10 months on the schedule.

And the client says, go for it.

So 170 miles away in Portland,

they start fabricating the steel module.

These panels are very large.

They were 14 feet tall and 30 to 40 feet long.

And they weighed on the order of about 9 tons each.

In October 2018, the first steel panels arrive

on site in Seattle.

As an engineer, this is a huge moment.

If it works, it will reduce the schedule by months.

If it doesn’t, it will be a disaster.

The team hold their breath as work gets underway.

The first job is putting the steel modules in place.

The core is composed of a bunch of sandwich panels.

And then they’re joined together

to the next panel to complete a core section.

Our panels were welded together.

We didn’t want to do a bolted connection

because having to line up bolt holes

is very, very difficult.

In the end, there was 26 miles of welding in this building.

Normally, you do not measure welding in miles.

That’s not a unit of measure that’s very typical.

As they’re filled with concrete, the tower shoots up.

The biggest difference is just seeing the units

put together at such a speed

that you’ve never really seen before.

They were able to set one entire floor of walls in a day,

in one day, as opposed to five days.

But as they get to 850 feet,

there’s a very different challenge--

the team needs to defy the laws of physics.

Pumping concrete at height

is really kind of technically challenging.

Just pumping something up 850 feet,

you need to overcome the force of gravity

to overcome the friction within the pipe.

To pull this off,

clearly any old concrete isn’t going to do the job.

We knew that it needed to be high strength.

It needed to be very flowable

because it was going to have to flow

from one module into the next.

So we worked on an appropriate mix.

What they came up with was a thinner mix

with no aggregate in it that would fill the modules.

The only downside was that it would take longer to set.

It’s a huge success.

The SpeedCore knocks months off the construction schedule,

leaving the team ready to face their next challenge--

the glass facade.

This is by far the most complex project that I’ve ever done,

and I think that we as a company have ever done.

In Seattle, work is about to begin

on the curving glass facade

that will maximize the tower’s floor space

while keeping the neighbors’ view.

But building it will be a nightmare.

The geometry of each floor is different,

so it just creates a lot of unique challenges for us.

There are steps up to level 40,

and each floor has a unique step inward to the building.

Usually, a skyscraper’s glass skin

hangs on an aluminum frame,

where the bars that hold the glass in place

slot together neatly, floor after floor.

But that doesn’t happen here.

Because every floor steps back a little,

the vertical bars don’t line up.

Instead of nice, clean, 90-degree angles

like you’d normally have,

every connection is off by a little bit.

To overcome this, they turn to a technology

used in aeronautics,

but rarely in construction.

What we ended up deciding to do

was look at a way to have a node

that was 3D printed out of aluminum

that kind of takes up all the geometric complexities

and into this printed part.

It turned out really good. It’s super precise.

With each set of connectors

individually printed,

the team can now seal the building

with the thousands of windows that make up the exterior.

It’s cool because no matter what side

of the building you look at

and what corner you’re looking at,

there’s so many unique aspects of it.

In September 2020,

the last window slides into place,

finishing the three-year build

and revealing Rainier Square Tower

in all its glory.

It’s the most iconic project that I’ve ever done,

and I think we’ve ever done as a company, too.

It’s up there, highlight of my career.

At 850 feet, the 58-story tower becomes

the tallest mixed-use building on Seattle’s skyline,

elegantly complementing the iconic tower next door.

Seattle has been changing significantly

over the years,

and to be able to add a significant project,

to me, this is

a once-in-a-lifetime opportunity.

With 734,000 square feet of office space

and 189 luxury apartments above,

it may dwarf the neighbors.

Its clever design, though, gives Ron

the best seat in the house to watch over it.

Every day that I came into my office,

I was able to see the progress,

I was able to see the speed at which things were happening,

and even somewhat frighteningly, seeing the steelworkers walking

on the steel beams in outer space,

30 or 40 stories in the air, right outside my window.

It actually gave me knots in my stomach.

Creating this tower

has truly been an incredible journey,

with results that speak for themselves.

Everyone came with this mentality of,

we don’t necessarily know how we’re gonna get it done today,

but we’re smart, and we’ll figure it out.

Would you use this toy to build a bridge?

In Brisbane, Australia, they did.

Well, sort of.

Architects use the same principles of tension

and compression that makes this toy enjoyable

to create one of the most revolutionary

and fun bridges on Earth.

How did they do that?

In the early 2000s, the city is growing fast.

It needs a new bridge to cross the Brisbane River,

linking the Northside’s busy city center

to the Arts District on the South Bank.

It was thought that it would be good

to have more connections across that river.

A pedestrian and cycle bridge out of the city,

so that more people would walk and be healthy and cycle.

So the city launches a competition for a bridge

that will complement Brisbane’s buzzing Arts District.

The bridge is located virtually

at the front door of the Gallery of Modern Art.

It needed to be a piece of art, a big piece of art.

The engineers behind the iconic Sydney Opera House

think they’ve got the winning idea.

We looked at lots of different bridge types,

but the one that met the brief best in terms of

being unusual and wonderful was this idea of

a lot of masts and cables

to make it look like a sculpture.

So how do you build a bridge

that’s also a work of art?

You attempt something that’s never been done before.

Use a little-known engineering principle called tensegrity.

Tensegrity exists in sculptures, like this,

where tension cables, like these,

hold isolated elements, like these rods, in place,

creating a stable, self-supporting structure.

Local architects Cox Rayner

are up for the challenge.

What excited us all was trying to do something

that hadn’t been done before.

The thing about tensegrity is it doesn’t make sense.

And that’s the mystery of tensegrity.

You end up with something that looks like it’s made

out of sticks and string,

or cat’s cradle, as my son called it when he first saw it.

The idea is that the entire bridge

will be supported from above

by this cat’s cradle system of poles and wires,

instead of by pillars underneath.

If they can pull it off, it’ll be a world’s first.

This was an opportunity to see,

can we apply the principles of tensegrity to a real solid,

big structure and make it effective?

The team hopes to build a bridge across

a 1,000-foot-wide bend in the Brisbane River

using tensegrity.

And that will be both highly functional

and look like a piece of art.

First, they will need to find somewhere

to construct the two supporting piers.

One in the river itself, clear of the shipping lane.

The other on the crowded North Bank,

home to an eight-lane freeway and bicycle path.

Next, they’ll have to find a way to support the bridge

while they build out from each pier.

And they need to make sure both sides meet in the middle.

Then, somehow, the entire bridge

needs to be supported from above

with a complex system of cables and wires.

And, as if that’s not enough,

the whole thing has to be finished in time

for the state of Queensland’s 150th birthday party

in two years.

This tensegrity bridge, it had never been attempted

anywhere in the world.

And we saw this as a milestone for Queensland.

The place chosen for the bridge

has great significance to the people who lived here first.

Before work can start,

the team consults with the local tribes.

For thousands of years,

it was the main crossing area for the tribes.

Parents would carry their babies on their shoulders

or even the mothers

on their babies because it wasn’t very deep.

There’s great cultural significance with

the particular bridge location.

We were a little bit nervous

that we might not be doing something

that the traditional owners thought appropriate.

They spoke to us

and asked us if we wanted to be involved.

And we gave the name for the bridge.

Kurilpa refers to the little kangaroo rat

that’s on the bend of the Brisbane River.

That’s the meaning.

Kuril is the little kangaroo rat,

and pa , place of.

With the bridge named Kurilpa,

work begins in December 2007.

The first job is finding somewhere to sink the two piers

that will anchor the bridge on each side of the river.

There were many challenges to the site.

One was we had to cross a freeway on the city side,

which was operational.

There’s a navigational channel as well,

which usually in this river is somewhat in the middle.

But in this particular location,

it was located over towards the South bank side.

A site is found in the river

that sits clear of the shipping lane.

But it brings many more challenges.

We had professional divers that had to go down

and dig the shelf and start the very first temporary pier

in muddy water that had basically zero vision

with great knots of water going through.

It’s critical that these piers

are gonna be strong enough

to withstand whatever nature throws at them.

The Brisbane River is well known to be prone to flooding.

So you try and make sure that A, you can resist the floodwaters,

but B, anything floating down the river on the floodwaters.

In Brisbane, Australia,

the team is in the middle of constructing

an extraordinary new pedestrian bridge,

which has to be tough enough to handle a collision.

The largest barge, I believe, is like

a 2,000-ton barge going out of a control,

coming down in a flood event.

So they had to withstand ship impact.

And that means anchoring it to the riverbed.

The main river pier of the Kurilpa Bridge is supported

on approximately 16 piles that go 18 feet into the rock.

They’re socketed in.

But the only way we were able to socket those in

is to basically drive through the alluvium

that was at the base of the riverbed.

Approximately 10 feet filled up with grout,

a bit of concrete for mass or damping effect.

They’re all joined together,

and we concreted the pole cap in there.

With the in-river pier secured

on the South Bank side,

the challenge is finding somewhere to build a pier

on the North Bank.

You had the Riverside Expressway,

which is the busiest motorway,

basically, in eastern Australia, or definitely in Brisbane.

You had the Bicentennial Bikeway.

And you had the Brisbane River itself.

The only space to squeeze it

is between the eight-lane expressway

and the city’s main bike path.

We had to carefully bring a pier up between the two structures

and also maintain the operation of the Riverside Expressway.

To keep the project on track

and traffic disruption to a minimum,

the team works through the night.

You can imagine all the lead-up work

to understand what the total numbers were

and understanding the peaks in traffic flow

in the Riverside Expressway

and actually how many night closures we’ll need,

how many day lane closures we had to make.

Very challenging.

After 12 months,

with both bridge piers in place,

attention turns to the next challenge.

How to build the 420-foot deck between them.

The problems of tensegrity

are to do with construction,

because it really only works when it’s finished.

All the cables are stretched, and they’re all taut,

and they all work in concert.

But when you’re building it, the cables are slack,

so nothing is supporting the bridge deck.

Where all the cables and poles are tight,

the system works together to create

this perfect balance of tension.

But when they’re not tight, the whole thing stops working.

There’s no support at all.

The team has to find a way

of supporting the bridge while they build it.

We wanted to avoid putting

any temporary piles or piers into the river itself

that would get in the way of navigation.

So it was a very intimate collaboration

between builder and engineer,

unusually intimate, to exactly work out

the construction methodology.

Their answer is to build the bridge out one mast and unit

of precast deck at a time

and hope it stays up.

There were many sleepless nights.

It was always a fear that something could drop

from that bridge under construction.

That was my main concern.

It was this idea of

a self-extending construction method.

You held up one bit of bridge

from a mast you’d already erected,

then you put down another mast,

and that held up the next bit of bridge.

As they build out,

temporary support struts hold up the bridge.

To make clear which are permanent massed,

the temporary supports are colored red.

We had a lot of temporary works there,

and that’s when the structure is challenged its most,

when it’s under those extreme forces

and under temporary works control.

You know, you’re going over one piece at a time,

you’re connecting one cable at a time,

and to make it all match up to the millimeter,

that was pretty challenging.

As both sides of the deck extend out,

the question is, will they meet in the middle?

As you build it, it moves a lot

’cause the cables stretch.

At some stages, it was up to a meter out of position.

So there was a nervousness.

You knew it had to be swaying

because there was nothing holding it there.

So as the last piece comes along,

you still don’t know,

because it’s still a long way out of position,

whether the piece will do the job it’s meant to do

and lower it just enough to make it join together.

But the bridge went in absolutely perfectly...

...which we thought was an astounding achievement

by the combined team.

It means the cat’s cradle of cables and masts

can be locked tight

to start holding up the bridge,

and temporary support struts can be removed.

It was a great moment.

Gave everybody a great sigh of relief and excitement.

But with less than four months until opening,

there’s a problem with the deck.

So since the Tacoma Narrows Bridge

in America, which failed in the 50s,

we’ve known that some bridges,

if they have very thin bridge decks,

are susceptible to galloping

or lateral torsional twisting in the wind,

where the bridge ends up collapsing because it twists

more and more and more as the wind goes.

Kurilpa Bridge was found to have that susceptibility

when we modeled it in a wind tunnel.

Which isn’t good news in a city like Brisbane

that’s vulnerable to tropical cyclones.

So the team comes up with an elegant engineering solution.

So we added little fairings on each side that just control

the wind enough to stop that effect.

The simple triangular fairings

improve its aerodynamics

so the wind flows over the walkway

and doesn’t catch it, making it twist.

It prevents it from starting,

and therefore you never get into that mode of instability.

Finally, on October 4th, 2009,

Kurilpa Bridge opens to the public.

And in time for the state’s 150th birthday.

I came up to Brisbane for the opening.

Everybody was overjoyed because it came out exactly as we hoped

it would at the beginning.

We just felt that we’d really created something

that contributed to the city.

I like it ’cause it’s an olive branch

that we were asked to be involved.

There was a time that wouldn’t even be

a second thought, to talk to

the traditional people from the area.

And at night,

a photovoltaic lighting system transforms it

into a colorful work of art.

The bridge is beautiful.

It allows people to stop on the way to sit above the river.

There’s little seats there.

It’s a wonderful sight.

I go for my runs every single day on it.

I use it for daily walking as well.

I use it every day I’m at work

so that I can go for a walk at lunchtime.

And then back up that hill, that’s a great workout.

I love it.

It’s just nothing like I’ve ever seen before.

I never really thought as project director

that it would put Brisbane on the map.

I couldn’t be more proud of this project.

A true world first.

Kurilpa Bridge takes its place

as one of the most audacious and technically ambitious

ever built.

♪ MTV ♪