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0:02
what happens when the world's most radical architect tries to revive a 100-year-old building this project obviously stands and folds with structure I mean this is a structural Masterpiece how is one of the world's tallest residential skyscrapers even standing columns are what make a building stand up you take away that structural support and and how do you create a building that would have been impossible just 10 years ago building
0:38
in water is incredibly difficult you've got to hold back an entire River while you're building this is the age of the extraordinary this house always is on the verge of falling down where ingenious Engineers have Unleashed un checked creativity everything in this building pushes at the boundaries of what's possible building structures so outrageous they defy Logic the forces on this thing look like it should be torn apart now their secrets are
1:16
revealed discovering the incredible stories of their construction these are extraordinary Feats of engineering to try and understand how did they build that
1:35
ever growing cities are in a constant battle for space risking demolishing the old to make way for the new but in antp Belgium one of Europe's busiest ports a forgotten 100-year old building has been transformed Beyond imagination a ground groundbreaking architect has turned this Historic Firehouse into a landing pad for an extension that is truly out of this world challenging Engineers to float the new edition effortlessly above the original building it leans forwards
2:17
it's backwards it it's completely offc Center on the legs manufacturing the entire structure off site and then shipping it in massive 400 ton pieces with dealing with making sure we protect this precious building that lies underneath breathing new life into every inch of its new home this is the antp port housee so how did they build it the antor Port Authority the government body that controls the busy Port needed a new home
2:56
they decided on a long forgotten Firehouse in the center of the industrial [Music] complex it needed some serious work if it was going to function as their new headquarters but they didn't want to demolish the original listed building adding to existing historical structures is a real challenge you've got the the technical challenge of being able to to work around and load and repair can be
3:27
quite old and historic material of the building but then you've also got the aesthetic and the kind of Heritage issues as well you need to build something that's going to be true to the original history and aesthetic of the structure or complement it in quite a a stark and interesting way they brought in one of the world's most famous Architects zaha Hadid to come up with a solution her Visionary designs like the guangju
3:56
Opera House were known for pushing engineering to the limits [Music]
4:05
this would be her last project completed before her untimely death in 2016 yuris pows would oversee the project on the ground this is maybe the biggest and most prominent existing building we've taken on to develop into a new overall project and it's definitely a challenge but it's something that we relish it's it's it gives all kinds of New Perspectives on uh on how to deal with existing fabric Urban fabric they had to
4:35
figure out how to build a futuristic extension to create extra space to have new offices while protecting a beautiful historic building that would form the rest of the port Authority's new headquarters the original design had four equal facades meaning there's no front entrance four facades were equally important so we definitely want wanted to preserve that quality of the existing building by building a volume on top and not blocking visually one of the main
5:06
facades The Architects also wanted to preserve the building's Central Courtyard conservation specialist Philip lemonier was charged with protecting this piece of antwerp's past making sure the radical design didn't destroy the building or Rob it of its original identity we can see in the typology of a fire station there a lot of elements one you can see on the the right side is that there are a lot of gates for fire trucks and then you have the
5:42
backside in the middle of the the facade the dry Tower those elements are very important for a fire station studying the plans for the firehouse gave the Architects an idea one that would honor the original design and let them build something out of this world it turns out the building was never actually finished it was built in 1921 and the original design of the fire station had a had a big tower on top which is twice the size of the building um
6:17
very extravagant was never built and which made us consider an extension on top of the existing building as a kind of contemporary end point to the existing building
6:34
this Monumental extension not only brings the building into the 21st century it completes the vision of the original architect the plan was to build a Precision engineered futuristic extension over 20 m above the historic building to house new offices supporting the 1500 ton structure with two massive concrete legs and to join the new extension to the Firehouse through the Old Tower where the firemen used to hang their hoses to
7:08
dry the engineers got to work figuring out how to support the massive steel structure above the 100-year-old Building without damaging it this project obviously stands and folds with structure I mean this is a this is a structural masterpiece we' like our buildings to float if we can so we we definitely try to minimize the points and and keep this idea of a hovering large hovering volume over the existing building the new building can levers out over the square
7:45
in front of the existing building it's quite a dramatic effect pointing towards the city center of antp the structure of the new building is a steel structure it's held by two concrete pillars
8:02
the engineers built the two concrete legs to hold up the new offices with the front leg designed to wildly lean out it looked dramatic but without precise calculations risked dropping the brand new building on top of the firehouse because the front leg is leaning out at an angle it's going to want to push out at the top and slip under the building at the bottom
8:32
they decided to connect the front and back legs at the top and bottom turning the structure into a massive concrete ring with the bottom part of that ring underground by connecting these two legs at the top they are kept from falling out of the top and at the bottom stopped from slipping in the two pillars are obviously not not vertical so the we have a very dramatically inclined front pillar which needs the concrete ring to
9:03
keep it from falling over the square so that's why this ring is very important as a structural element the ring is joined just under the massive steel and glass structure and the bottom connects three stories underground in the car park keeping the legs in place and letting them support the weight of the extension the top section stops the giant concrete leg from falling over and the bottom stops IT sliding out from under
9:33
the massive steel structure then the whole thing is steadied by another four interconnected steel supports the engineers did all this whilst barely touching The Old [Music] Firehouse we try to keep the impact on the existing building very minimal and that is equally important when we created this structural ring which goes through the the foundation work of the existing uh building so it's a very minimal connection both structurally where we connect the foundations as
10:13
well as physically where we introduced a small staircase leading up to the entrance hall in inside the existing building we've got a twostory underground car parking so it's two stories down underneath that what third basement level if you like that's where we made a connection between the foundation of that inclined front pillar and the central pillar which rests in the courtyard what did the conservation specialist think of this radical approach did it do justice
10:48
to the original building the opportunity to do the the second feet at the inside of the building in the courtyard but but we still need it to have the the aspect of a courtyard you can fill it up with feeds and and structure then you have no more Courtyard and you have no more lights inside you can use even more this uh space so the engineer and zit try to find a way that you could have the
11:20
this structure but with a kind of subtility that these are sculptural elements in the inside and so you can see that those element even not touch the old structure Just Landing inside the building and they make possible that this uh big volume above our head is standing over there with the gigantic concrete legs in place the engineers were ready to tackle the futuristic glass structure but constructing it was going to be a bigger undertaking than anyone had imagined
12:00
having the new building floating in midair uh it's important that that's not a super heavy construction so it's a steel structure um it also is a sustainable structure so we looked at a whole number of possibilities of constructing the building uh we did a lot of analysis with the contractor uh to see how they could build platforms how they could get enough people up there to preserve the original building and realign the precise design the engineers decided
12:31
to build almost all of the new extension in a factory 90 km away it was clear after an initial analysis that building the steel structure offside in in big modules shipping them to site and installing them was a much faster and more economical way of constructing the building normally with steel structures you build upwards with scaffolding support and Welding as you go but in this case they were building over the existing structure you're
13:02
looking at a lot of scaffolding support with all the risks of building over and around this listed precious building so what do you do you build it 90 km away in 400 ton pieces and ship it in so building the structure of the new building offside uh in Factory means it's much more controlled in terms of tolerances making sure everything is completely right they even installed an temporary structure to ship the modules on boats to the location uh
13:37
and then all they had to do is lift them in place so it's a much faster construction procedure to build the overall volume the structure of the new building is built in six separate steel parts two steel pieces per level and they were lifted in place and then assembled on top of the existing building the 100 m long 60 M high and 20 M wide steel structure was broken up into six enormous 400 ton pieces and shipped from the factory 90 km away on massive barges the builders used a
14:17
remote control Dolly system to offload these giant sections so it's it's both light construction so lightweight construction time which is important and also the kind of environmental concern that we had so this is achieved by by having this steel structure made offside and coming onite by boat the scale of this job is immense just just look at the size of the platforms that are used to drive
14:48
off the sections from the barges they're each the size of a truck it it just seems mad that this is the safest and quickest and and most efficient way of working but it just illustrates that to make a building like this you really have to approach it from a completely different way of thinking with the steel Mega structure in place they turned their attention to the building's signature glass
15:16
facade we wanted the glass volume to maximize views out maximum light coming into the office environment and what we looked at is to create a dynamic over the length of the facade as if this building is in motion um and we did that by playing with the faceted triangles that go from a flat facade on the south side to a completely faceted pineapple structure on the North side so this transition makes that when you observe the building from distance it's in seems to be in
15:52
constant flux with light with clouds with sunlight playing on the triangles it seems to be a kind of moving object over the static classical building the finished effect means the glass is constantly changing as you walk around it there's something of the effect of the glittering sea or fishy scales the gigantic extension was Secure glistening Above The Old Firehouse but there was still no physical connection between the two structures how do you connect two
16:27
massive buildings with the least impact [Music] possible they decided to use the firehouses old dry Tower you do an extension to a building at one place or at one moment the two parts have a place where they meet together what we see is the maybe the only physical touch between old and new is the dry Tower when we see the the dry Tower we see a little bit of masonry up above the roof and then we see a start of a glazing elevator chaft the
17:04
elevator starts in the old dry Tower go to the glazing shaft and then enter in the new building although you you enter the lifts at the bottom of the existing building in the tower uh the lifts take you up to the new building and connect but the structure of these lifts is hung independently from the steel structure of the new building so there is it's not actually touching the brick work of the existing Tower the existing brick
17:37
work Tower acts as a sleeve in which the steel structure is hung independently from the brick work completely loose from each other the amazing thing is that both of these buildings are separate replace the bricks and good as new of course that would be a very expensive change of heart
18:01
the radical new extension was in place transforming the original fire station seamlessly combining groundbreaking architecture with a sense of History to bring a forgotten Firehouse into the 21st century I think actually that our project allowed this building to be reinstated as an important Landmark within the antp urban fabric there might have been all kinds of other scenarios where this building would have been demolished and something new would have been built and I think it
18:32
was very important also for zaha herself to keep this existing building to to to stay with this and to have a separate layer coming over it to layer the city instead of demolishing and rebuilding something we have a larger building with a bigger capacity uh working 500 people in it now and we have also a remarkable site now here a site may be forgotten uh in the past what we have here is a building that deeply respects the original and gives it space yet
19:09
it also reacts against it with something so crazy and outlandish the overall effect is that we have these two structures that exist together but have their own [Music] identity
19:35
deep in the heart of New York's Manhattan Island one of the most prestigious addresses in the city has a new Resident an 88 story skyscraper one of the highest residential Towers in the world it's classed as a super tool there's only about 146 of them in the world it's really become a club that people are desperate to be a part of not just tall in the extreme at just 28 M across it's also very slim and vulnerable to the city's wild winds 432 Park Avenue is 15 times higher
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than the width at its base to create luxury apartments with unspoiled views the engineers had to do away with internal columns the project was would cost $1.25 billion and push skyscraper engineering to its limits this gravity defying wonder is 432 Park Avenue so how did they build it it's 2011 and on a small plot in Manhattan an ambitious plan is being put into action to build a 28 M wide Tower 426 M into the sky Dimensions never seen before in skyscraper
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engineering engineer hsy Mana was tasked with figuring out how to build this developer's Dream It's not a normal typical building it's very tall small footprint it's very slander there's a lot of challenges is a tremendous effort uh put in for over 5 years from start to finish this super tall super slim design was difficult enough to build as it was but there was another curveball coming the engineer's way with Apartments needing to fetch 75 million plus no
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one wanted internal columns getting in the way of luxury Interiors they told the engineers to get rid of them taking away columns is all well and good but unfortunately they they're very important for holding up the structure if you take them away then you need an alternative way to carry those loads down to the ground columns are what make a building stand up you take away that structural support
22:21
and with a building this tall you need a way to hold up the weight of 88 floors normally this is done with internal columns without them they needed a way to support this super tall skyscraper so like a typical 20 30 story building would have a central core what we call the backbone of the building and that will hold the wind and the earthquake seismic horizontal forces this is the backbone of the building it's what gives buildings their strength
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for 432 Park Avenue at 88 stories high that wasn't enough the engineers decided to make the buildings outer shells super strong to reinforce the [Music] structure this building has a backbone which is also the central core uh but we also supplemented the exterior columns so together they are providing the stability that the building needs they inserted super sized steel rebar into the concrete outer shell for added strength to
23:33
make concrete stronger you put steel reinforcement into it and in this case it's a gigantic piece of Steel Architects Chuck naap and Gloria glass kept a section of this super thick rebar as a souvenir you can see the size and the diameter these are major rear and and in general there the size you know right right and the deformations on the side of the bar normally um not this this is screwed
24:02
because they need to be able to screw these into couplers so it is a it's a different animal um but it's pretty big and this this thing is only about an inch inch and a half and it's very very heavy it wasn't enough though just to have a super strong facade it had to be tied to the core of the building that area that houses the Elevator Shaft this super sized rebar made the outside of the skyscraper incredibly strong but the engineers made it even stronger connecting
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it with steel beams to the concrete Elevator Shaft which acts like a spine running down the length of the building the skyscraper's core and reinforced exterior gave it the strength to Tower 426 m in the air but this height made it vulnerable to New York's infamous winds a skyscraper is a structure that people live in you hang out there you sleep there and if the Architects and Engineers don't do anything about the wind then you're really going to feel it especially if the
25:13
building's thin all structures that we build move but in tall structures they're particularly prone to being moved by the wind and the thinner the structure the more vulnerable they are the skyscrape was vulnerable to turbulence created by the wind if the wind was strong enough it could make the building Shake making it uninhabitable and even risking damage to the structure when you have a tall thin structure like this and when the wind strikes it the wind
25:46
then wants to pass around the building creating turbulence on the back side that turbulence creates vortices and SRS of wind which pass up the full height of the building and the turbulence creates the swrs to First be on one side and then the other and then the other this is called Vortex shedding and what it does is it starts to actually Buffet the building sideways even though you're blowing it straight on now any building has a natural frequency think about pushing a child
26:11
on a swing if you push it at the right push the child at the right frequency the child will start to go higher same thing happens to a building if these vortices start to form and push the building at the right or the wrong frequency then the vibration will start to get out of control the engineers started to take out windows letting the wind rush through floors that contain the skyscrapers pumps and other utilities well we found that when you make these penetrations
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in the building at certain locations it reduces the wind pressures by about 20 to 25% every 12th floor is open to the air that lets the wind blow through really clever but it doesn't solve the problem completely to make sure the skyscraper could even survive New York's strongest winds the engineers had another trick up their sleeves the master stroke the brilliant engineering trick is hidden away at the very top of the tower on the 84th floor two secret
27:17
giant machines that directly counteract the wind the wind acting on the building wants to make it sway to stop that happening then they've use tuned Mass dampers which means a huge lump of concrete high up in the building it's an active system which means that when the building wants to swear in One Direction the hydraulic jacks will move that lump of concrete in the other direction counteracting that force and hopefully keeping the building
27:42
uh not moving too much in this particular building we have a damper weighs about 1,300 tons absorbing the energy of the wind that exerts on the building so it has to be fast enough so that the occupant that sits in the apartment doesn't feel that the movement of the building which is good news if you've paid over $75 million for one of the incredible Apartments 432 is without a doubt a feat of world-class engineering it cost a staggering $1.25 billion us to build and by
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my estimation it's about as beautiful as a skyscraper can [Music] get 432 Park Avenue Towers above the competition giving one of the most sought after addresses in New York its best view as well using clever engineering to take skyscrapers to their limits [Music]
29:08
on the rugged east coast of Scotland a ship building Powerhouse had fallen quiet but all of that was about to change thanks to one extraordinary structure the brainchild of one of the world's most radical architects the Victoria and Albert Museum in Dundee rises from the river Tay forming a man-made Cliff this revolutionary design forced Engineers to construct a huge dam in the middle of a raging river build a gravity defying 8,000 squ M shell in one piece of concrete without a
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column in sight and hang three ton slabs of impossible walls it looks like the forces of this building should just completely rip it [Music] apart so how did they build it in dunde Scotland the city's industrial heart needed a kickart the radical plan was to build Scotland's first design Museum in the historic shipyards where Scott and shackleton's legendary Antarctic ship had been built
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it's been very important in this project to have a remarkable building this is a new design Museum so it seemed right to look for an ambitious design it would inspire people to come and see the building a building by an architect who was so brilliant at responding to a particular place about the relationship between the river and the city Visionary Japanese architect Kango Kuma designed this brutalist masterpiece
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he used Scotland's stunning landscape for inspiration the oaking island we found a beautiful C reminds me the spirit of scotand because is very tough and the nature is very tough but still the cliff is fighting with the tough Natures reminds me the history of scotand and the culture of Scotland
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the plan to lay the foundations in the middle of the Tay River whilst battling the Scottish weather and protecting local Wildlife to Cast a Giant concrete shell that uses nothing but its own strangely shaped walls for support and hang the signature cladding with pieces weighing up to 3 tons from the gravity defying walls
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their first task was to lay the foundations but this wasn't going to be easy the design called for a huge portion of the building to stick out into the Tay there are serious issues with building in water building in water is incredibly difficult you've got to hold back an entire River While You're Building how do you lay foundations in the middle of a river
32:28
structural engineer Dan kpsom had to tackle this Monumental task building the water isn't fundamentally different from building on the ground the foundations of the building still need to go down to bedrock so whether it's in the river or on the land behind the river wall we're still piling down 20 M into the Rock to get a good foundation for the building dund is a a very nice sunny City most of the time it's also cold and wet in winter like many places so the weather
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plays quite a key part in construction we're working by a tidal River working in a climate that has extreme cold during the winter and rain and winds they all need to be considered during construction they had to lay the foundations on a seriously difficult site to make it possible they decided to build a dam out of 12,500 tons of stone and Earth called a coffer Dam Coffer dam is an enclosure built within a body of water to to allow the enclosed area to be pumped out
33:30
that means that you can get on with your work in a nice dry environment the coffa dam would let the engineers extend the existing doc side pushing the site into the Tay building the dam was a rate against time there are protected species in the river particularly uh a species of seal and so we had a very short time scale that would allow us to build our foundation out in the river we went on site in March in 2015 and we had to make sure that all of that work that was done
34:04
out in the river was done by the beginning of June the beginning of the seal popping season the local grey seal population lives close to the site their breeding season was just around the corner and the second it started all work in the river would have to stop they'd have to work quickly the construction team hammered massive steel slats into the riverbed filling in the center with rubble to hold back the force of the Tay River what was done in this case
34:37
was a temporary bit of land was created so the contractor installed a piled wall out into the river and filled it in with ground to create a new bit of land that we could then build the building on we were constructing the building on top of Solid Ground even though it was above the river the engineers drilled down 20 M anchoring the buildings foundations to the Bedrock on concrete piles at the same time they had to make sure the corrosive salt of the Tay wouldn't eat away the
35:06
foundations they decided to use a concrete with a special formula specifically designed to resist salt salt and chlorides are the enemy of our structure so they cause corrosion and damage to the building over time that we have to prevent the concrete mixes we've used in this building had to be different we had to change them from what we' normally do in order to make them more resistant to the elements to the salts to all of the things that are trying to attack the building
35:35
the foundations were secure and a new piece of land had been built into the Tay River ready for the next step of the build the engineers now had to tackle the building's radical shape they wanted the walls to support the entire structure removing any interior columns from the galleries spaces but the Leaning and twisting design threatened to tear the museum [Music] apart normally you would never build walls that are sloping outwards and that's because as well as
36:11
the usual gravitational forces that are pushing down on the building you're adding an extra layer of strain as the walls are being pulled apart the shape of this building is it's really incredible and something that you don't see in architecture very often for a reason and that's because it just takes a lot of expertise science and maths to achieve what they've achieved here to get the calculations right they used the very latest 3D computer modeling and sculptural techniques this
36:42
is a building that is a very modern design we needed to use a lot of computational power to create the design of this building we looked at the shape at at the concept stage and we could have put a frame in here and hung the facade off the outside of it it could have been a traditional building the problem problem with that is we'd fill the building with a lot of stuff and this is a museum this is an art space this is a gallery this is a place for people to
37:03
come and enjoy that we didn't want to fill with bits of Steel and concrete historically we'd build buildings with the walls carrying the weights Stone Huts back in the Dark Ages the walls carried the roof and that was how he protected you from the wind and the rain so we took the option of using the Shell of the building as it structure kind of going back to the old way of doing things make the outside of the building hold the building up
37:25
and then you don't need to put anything inside because of the way the building is pulling on all the different bits of itself the roof pulls on the walls the walls pull on the roof we had to design it as one big object to make the most of the exhibition spaces the architect didn't want any interior columns to achieve this the shell of the building the exterior walls had to support the roof and themselves No Easy Task given their extreme shapes the solution was to design the
37:58
shell to work as one piece using its own weight and steel reinforcements to hold the building together but there was a problem the shell would only be structurally sound when the last piece was in place until then the whole building was unstable so the Leaning walls and the whole building is really held together by these tension forces pulling everything back towards that Central Cor the skin of the building itself is doing all the work it's carrying
38:31
the weight of the building it's pushing and pulling with different forces it's resisting the wind and the rain it's keeping the building watertight holding the facade up and the cladding on the outside but it's primarily supporting the building they used their Advanced Computer model to make the walls super efficient making them as thin as possible and more importantly light uh that resulted in some of the walls being half as thick they went from 600 mm down to 300 mm uh
38:59
which is a significant saving in materials and reduces the weight of the building the size of the foundations you know there's a lot of positive outcomes from that now they faced the challenge of building the 2,300 cubic meter shell this would only be stable when the last pore of concrete had hardened it wouldn't be able to support its own weight until the very end cuz the shell we had to make it was like casting a giant mold we had to finish the casting
39:31
before we could take the mold away because in a partially completed State the building isn't stable as the shells started to go up the builders had to add more and more formwork the molds that hold the concrete to support the precarious structure if they removed a piece too early the whole structure would collapse after a year and a half of of constant work the last concrete por was completed it was time to take off the formwork and see if all the calculations
40:04
were correct and this one-of-a-kind design would support itself finally after nearly 2 years of it coming into place it came down and it was a very very exciting moment to see that formwork removed and the shell or VNA dunde uh finally born Finally Revealed
40:28
when the molds were removed the black concrete underneath was revealed colorized with PFA paint or pulverized fuel Ash made from the waste of coal fired power stations at last the v's groundbreaking shell was complete but architect Kango Kuma wasn't going to leave it there he had big plans for the Finish instead of vertical wall we tried to bring that kind of pure natural formation to the building he wanted to use giant concrete blocks to mimic the craggy appearance of Scottish
41:09
Coastal Cliffs but it turns out creating a random natural pattern is harder than you think if you look at the facade of the building at the external panels from outside you'll see that they all look slightly different um there's a random pattern to them they step in and out they step up and down they kind of weave around and create this sort of vision of this Cliff face of this random assortment in reality they're not that random if we did an
41:40
entirely random pattern for the facade if every plank was just generated by some mathematical formula the risk is that two or three planks next to each other would look similar enough that your brain would see them as the same so we had to create this algorithm that allowed us to fine-tune things to make sure the Architects could look at the building from every angle and they could tweak and adjust until it looked just just so with the shell working as one piece
42:04
it was ready to take the massive weight of all the cladding all in all there are 2,500 preast rough Stone panels weighing up to 3,000 kg each and spanning up to 4 M hanging them was going to be a challenge the facade panels are made from a concrete and constituted Stone material they weigh an awful lot the facade the panels weigh about the same as the wall that's holding them up panels on a more vertical wall are smaller panels on a more sloping walls are bigger that
42:37
presents another challenge because the the walls that are sloping and twisting are working harder and the cladding hung off them is heavier so it's a sort of double whammy of challenge that we had to overcome in the design the anchoring points of the giant Stone cladding had to be seriously heavy duty the engineers decided to set them in the the shell when it was first being poured letting the outer shell Harden around them this though left no room for error get it wrong and
43:07
the cladding wouldn't fit on the shell in the end every Anchor Bar three was in the perfect position the exterior of the building was complete a testament to the Scottish landscape the VNA dunde is proof that radical engineering can breathe new life into a long neglected area using the natural environment to redefine the urban landscape the end result is a beautiful building that is truly built to last as as tough and rugged and and as beautiful as
43:51
the Scottish landscape that inspired it dund is falling in love with its waterfront again and uh people that come to experience VNA dunde now have a new relationship with the river which has been such an important part of this city extraordinary engineering challenges have been overcome to create the designer's vision I consider this to be a landmark project I find it fascinating that people look at it as a piece of engineering as well as a piece
44:21
of art and architecture it's a a visible piece of Structural Engineering [Music] e
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