"Today, on "Impossible engineering,"" "the Shard, a record-breaking super tower..." "Construction never been attempted before on a building this tall in central London." "Taking structural design to new heights." "It's amazing to think the first 21 stories of this concrete structure went up before they'd even finished the foundations below." "It took revolutionary engineering..." "Look at the crazy amounts of glass that this building uses:" "11,000 separate pieces." "What a stunning sight." "To make the impossible possible. captions paid for by discovery communications" "Some of the world's most iconic buildings dominate its skyline." "And, in 2012, a modern marvel was constructed, altering the city's look forever." "Meet the Shard." "At 1,016 feet tall, this futuristic skyscraper is the tallest in London." "Wow." "Look at that." "It looks like a piece of crystal, a splinter coming up through the earth." "It's so tall." "And it's such a prominent part of the skyline that you can't help but notice it." "That's an incredibly audacious piece of architecture and some very impressive engineering." "The Shard rises up from the heart of downtown London." "This jaw-dropping tower is over three times the height of the statue of Liberty." "Its facade is made out of a staggering 11,000 glass panels." "That's enough glass to cover 130 basketball courts." "Beneath the 196-foot spire lies the spine of the building." "The colossal concrete core supports 72 levels, totaling over a million square feet of floor space." "Building these buildings is always exciting." "You're building up taller than anybody's gone in Europe." "But this one was particularly difficult." "The population in London is surging." "It's estimated that the city could reach 10 million inhabitants by 2030." "With limited room to grow, designers of any new buildings are looking to the skies." "Looking across the London skyline as we approach from the south, you can really see, it's just crowded." "There's buildings everywhere." "Building in that tight space is a very, very difficult task." "Finding enough open space to build a mega tower in this bustling city is a seemingly impossible challenge." "It's in this congested site just in the corner of a railway station, things going on all the way around it." "We had no spare site in which to build it." "It's smack in the center of London with London bridge station on one side, guy's hospital tower on the other, the jubilee line of the two passing very close underneath." "And to add to all of that complexity, there was a building already on this site that needed to be removed before construction could begin." "The 25,000-ton weight of the old tower is problematic for the engineering team." "When you put a building on the ground, the very heavy weight compresses the soil." "It's like a sponge." "It creates a divot where the building is." "And when you take that weight off, the ground wants to heave, wants to respond and go back to where it was originally." "And time is of the essence." "You want to put the weight back onto that ground as quickly as you can." "Building the Shard on this site would be impossible without help from a great innovator from the past." "When it comes to building up..." " There we go." "Man has always defied the odds." "Well done." "Well done." "The builders of ancient Petra carved vast structures out of sandstone cliffs in the Jordan desert..." " Very good." "Safely perched on a series of giant stone steps." "Oops." "Sorry!" "In 12th-century Italy, warring noble families in bologna erected over 100 towers." "Bigger was definitely better." "Mama Mia, what a whopper!" "Perhaps the first skyscraper city was 16th-century Shibam in Yemen." "Adopting ancient techniques, its engineers used mud bricks to build high-rises that were so impressive, it's known as the Manhattan of the desert." "In the 1950s, the bustling Italian city of Milan wanted to build a subway." "But tearing up the city streets simply wasn't an option." "Engineers needed to figure out a way to build without disrupting city life." "We've come here to a site where the Metro network is being expanded." "Being here and seeing the scale of this site, you can imagine the tremendous disruption it would be causing if you tried to do this in the center of the city..." "Really an enormous challenge." "Poor soil conditions made tunneling beneath the city streets nearly impossible." "This is actually a really good illustration of one of the key problems here in Milan." "We're down here at the bottom of the excavation." "And you can see this is an area where they're just getting ready to start to dig a tunnel." "And the engineers have gone to really heroic efforts there." "Around that wall, you can see they've put some rubber gasket." "And they've really tried to keep the water out of the site." "But, in spite of that, you can see how much water is still flowing in." "So these are about the worst conditions you could hope to be digging tunnels in." "Engineer Dr. Christian Veder came up with a brilliant solution." "Before Veder, a technique called cut-and-cover was the go-to option for tunnelers." "Let's imagine that I want to dig a trench down between these buildings." "And you can see what happens when I do that in this Sandy soil." "Initially, there's no problem." "But if I push just a little bit too far, you can see that, eventually, I destabilize the soil and my structures will fall into the trench." "And, obviously, that's completely unacceptable on a site in a congested urban center." "Veder turned the cut-and-cover concept on its head." "Instead of building one big trench initially, he built two little trenches down the sides of the buildings." "And into those trenches, he inserted reinforced concrete walls." "And these then became known as diaphragm walls." "After dropping in diaphragm walls," "Veder built a roof over the tunnel, allowing city traffic to resume above." "Digging, tunneling and construction could take place without disrupting life in Milan." "Instead of cut-and-cover," "Veder's technique covered, then cut." "It's now known as top-down." "This method was adapted around the world as a way of completing major subterranean projects with little to no interruption to the world above." "So what Veder achieved here in Milan was to pioneer a really innovative construction method." "And it's fair to say that, standing down here in one of the new tunnels of the Milan Metro, it simply wouldn't exist without that construction technique." "In 2009, engineers at the Shard take Veder's top-down method and turn it on its head." "Normally, a building like this would be built by building a basement first and digging a big hole down to the bottom level of the basement." "And then starting the..." "The core from that lowest level and building upwards." "Now, we built the core on stilts effectively but held up the core while we were building it upwards." "And then we were, at the same time, digging underneath it and going downwards." "That had never been done before." "It was an innovation for the Shard." "Just 23 piles support the Shard's concrete core as it rises from a void in basement level two." "As excavations of the underground floors continue around the pre-sunk columns, the core rises as if balanced on a tabletop above." "This allowed the engineers to shave, literally, months off this project." "And the Shard was built much more quickly and much more cheaply than it could otherwise have been." "This really is an engineering marvel." "Pouring the Shard's 800-foot concrete core requires an epic engineering solution." "It's amazing to think the first 21 stories of this concrete structure went up before they'd even finished the foundations below." "At 1,016 feet, the Shard in London is taller than the Eiffel Tower." "It has 72 habitable floors, 44 elevators and 306 flights of stairs." "Building this mega tower required almost 2 million cubic feet of concrete." "The Shard is an incredible building." "It just stands high, proud above the London skyline." "And this incredible bit of architecture really does put London on the map." "This is a really radical building." "It imposes on the London skyline like nothing else." "It ascends into the air." "And the whole thing shines and glistens in the sun." "What a stunning sight." "The Shard's luxury apartments, hotel, and nearly 600,000 square feet of office space have set a new benchmark in skyscraper design." "But huge ambition comes at a price." "The $618 million project required more than 1,400 workers on-site." "As soon as a project like this starts, you're against the clock every second of the day." "Time is money." "You need to keep going and keep going quickly." "The slow bit of construction is building a concrete core that is the real basis of stability for the structure." "It holds the building up, holds the building solid against wind loads and is a very, very important part of the building." "And getting that in... in place quickly is a real challenge." "The Shard's concrete floor consists of over 350,000 cubic feet of concrete." "Constructing it would've been impossible had it not been for a groundbreaking method developed over 100 years ago." "Architectural historian Jen Masengarb is in Minneapolis, seeing for herself how an innovation in the baking industry is influencing building construction around the world." "In the 1880s, Minneapolis was known as the flour capital of the world." "Raw grain was brought here from across the northern prairie, processed here and then shipped across the country and around the world." "Flour production in the 19th century was dangerous business." "Dry millstones could ignite flour dust, causing catastrophic explosions inside wooden silos." "In 1878, the Washburn a, one of the largest mills in the city, exploded, killing 18." "Grain merchants were facing a storage problem, so, clearly, a new solution was needed." "Their answer came from engineer Charles Haglin and grain trader frank Peavey." "Together, they designed a safer, stronger silo." "So, this is what they constructed:" "The world's first reinforced concrete grain silo." "The technique that Haglin developed for the cylindrical shape was absolutely revolutionary for its time." "Haglin built a wooden cylindrical mold and filled it with concrete." "Once the concrete set, the mold was removed and placed on top of the first section." "Haglin repeated this process until he reached his desired height." "Many of Haglin's peers didn't think that concrete could hold grain, so Haglin's experimental tower was filled and tested." "So, Peavey and Haglin's experiment worked." "They had solved the grain storage problem, and they could take what they learned here and use it all over the state." "Inspired by his experimental silo, in 1908, Haglin built the Washburn-Crosby elevator one, part of the Washburn a mill." "At its peak, it could produce almost 2 million pounds of flour a day." "The most innovative thing about this design are these 15 cylindrical silos, each measuring about 100 feet tall." "Constructed by Charles Haglin, they were the first large-scale, concrete grain silos in the U.S." "To build the silos, Haglin developed an ingenuous new method called slip forming." "His new technique allowed him to continually move the concrete-filled mold." "So, what we've got here is a simple demonstration of how slip forming works." "I've got this bucket of slightly wet sand here." "This is gonna represent our concrete." "And I've got this other bucket here with a hole cut in the top." "This is gonna represent our slip form." "And here's how the process works." "A little of the concrete goes in." "And, slowly, about a few inches every hour, the slip form gets raised up and up." "And then I add a little more." "And raised up a little bit higher." "The rig is continually forced up by hydraulic Jacks while concrete is poured nonstop." "The concrete at the top remains wet and fluid." "By the time the concrete emerges from the bottom of the moving mold, it's dry enough to support the growing structure." "The combination of the speed of the rig, how fast the slip forming moves up the structure and the fact that the concrete has to be poured continuously into the top so that the top layer never fully cures," "this is the key to making this whole process work." "Haglin's rig was so efficient, it could scale 8 feet in just 24 hours." "Each cylinder was poured in just 12 days." "Haglin's use of slip form construction revolutionized the way that tall buildings are constructed." "And, today, concrete has become one of the most widely used materials in construction, allowing us to build higher and faster than ever." "At over 800 feet, the Shard's concrete core is nearly eight times taller than the Washburn-Crosby elevator silos." "Engineers used a super-sized version of Haglin's pioneering rig." "The giant slip form rig measured 85-by-72 feet." "It was moving upwards at 3 meters a day, almost a floor a day." "You have steel shutters, which form the shape of the concrete." "And then they are moved up almost continuously, 6 days a week, 24 hours a day." "Thanks to a high-capacity concrete pump, the system was so efficient, it reached the 21st floor in just 10 weeks." "It's amazing to think the first 21 stories of this concrete structure went up before they'd even finished the foundations below." "The concrete core is still sitting on just 23 piles in the center of the basement." "Engineers need to pour the rest of the foundation before they can continue building up the core." "This includes basement level three's raft foundation..." "A massive concrete pour." "It took 32 hours." "We poured the whole thing in one go." "It's as much as 3 meters thick in the middle, underneath the core." "And it was 5,500 cubic meters of concrete." "They had trucks coming in from three different concrete plants." "It was tremendously exciting to see all that concrete arriving on-site." "To finish the Shard, engineers are bringing in some of the tallest, most powerful tower cranes in the world." "They started with four cranes at ground level." "Those went up to about 160 meters." "But, above that, we've still got 140 meters of the building to go." "How do we get the structure, the construction equipment up to that height?" "A daring engineering solution is needed." "In 2012, London's skyline was transformed." "Three times taller than the statue of Liberty, the Shard dwarfs everything around it." "Two of its biggest fans, physicist Andrew Steele and engineer" "David knight are taking in this architectural masterpiece from every angle." "This is London's Burj Khalifa." "This is London's Shanghai tower." "It was built in very trying circumstances and at speed." "And London engineers are really proud of that achievement." "Built from a central concrete core, the tower's unique, hybrid superstructure is pulled up around it." "40 floors, constructed of steel, 29 stories of concrete, topped off by a monumental, 23-story spire at the pinnacle of the building." "Building a tower this tall in the middle of London presents some unique logistical challenges." "When you're building a tower that's over 300 meters high, one of the real challenges is getting the people and the materials up to these incredible heights when you're doing the construction." "And the higher the tower gets, the harder that challenge becomes." "Construction had never been attempted before on a building this tall in central London." "And it was a real challenge to get men and materials up to the top floor." "So how do you get enormous amounts of building material to the top of a mega tower like the Shard?" "It would be impossible without help from the innovators of the past." "To construct the great pyramids, the ancient Egyptians had to rely on elbow grease and a lot of determination to scale their network of ramps." "As cranes were introduced, the treadwheel allowed engineers to use leg power with impressive results." "Faster, faster!" "Only walking pace was recommended." "Erecting a giant obelisk in 16th-century Rome required even more muscle." "It took 800 men to raise a vast lifting tower." "Ah-choo!" "Plenty of power to get it up as long as no one let you down." "A more reliable solution to heavy weight-lifting came 3 centuries later." "Dr. Rhys Morgan is exploring the waterways of Venice, soaking in a centuries-old seafaring tradition, which ultimately led to an engineering innovation." "Throughout history, this city has had an unshakable affiliation with all things waterborne." "And the mid to late 19th-century was no different." "It was a time of great change in the maritime industry." "And old, wooden galleys propelled by oar and wind were being replaced by steel-hull ships and great, big engines." "This new wave of heavyweight ships posed a huge problem for engineers at Venice's historic naval shipyard, the arsenal." "Traditional, manually operated cranes couldn't handle heavy loads." "This seriously compromised the Italian Navy's boat-building program." "They turned to British engineer sir William Armstrong." "He came up with the perfect solution to Venice's maritime construction conundrum." "Because of the growing trend of metal-hull construction, the Navy decided to commission just the thing for the arsenale." "And here it is." "A stunning Armstrong crane." "Completed in 1885, this colossal structure is an imposing addition to the venetian skyline." "And today, Rhys has special access to its inner workings." "And the way it works is like this." "This huge boiler would generate enormous amounts of steam." "And that steam would flow up through the pipework, down into these chambers below." "The steam drove these enormous pistons back and forth, back and forth." "And they, in turn, helped pressurize the hydraulic circuit." "The water was taken from the lagoon outside." "And the pressure from the pistons generated huge amounts of pressure on the hydraulic system itself." "The Armstrong crane can lift what was, at the time, an unimaginable 160-ton load." "It transformed the fortunes of arsenal." "It was the power that meant that previously unimaginable weights could be lifted." "And it opened up a whole new frontier in crane technology." "Over a 30-year period, nine more of Armstrong's cranes were installed around the world, ushering in a new era in crane development." "By pushing the boundaries of what cranes were capable of," "Armstrong created a landmark in engineering history and paved the way for incredible projects that we see all around the world today." "Engineers at the Shard took Armstrong's historic crane design to the next level." "Building this superstructure meant building some of the tallest, most powerful tower cranes in the world." "They started with four cranes at ground level." "Those went up to about 160 meters." "But, above that, we've still got 140 meters of the building to go." "How do we get the structure, the construction equipment up to that height?" "Engineer John Parker and his team came up with a radical idea." "Mounting a tower crane to the Shard's concrete core." "What was unique about the Shard was that the tower crane was supported on that slip form." "Usually, you have to fix the crane to the concrete." "We avoided all that so they could both go up together." "As hydraulic Jacks pushed the core and crane higher, the machinery is kept stable against wind speeds in excess of 100 miles per hour by extending the lower section of the crane into one of the already cast lift shafts." "Installing the Shard's spire required an even more radical approach." "They then had to use the crane that was attached to the slip form to build another crane which cantilevered off the main building and allowed them to build this final spire on top of the structure." "Engineers elevate the tower crane to a staggering 1,040 feet, enabling them to install the custom-built steel sections that form the 23-story spire." "The section could arrive on a truck." "They could attach it to the crane, lift it up to the top, bolt it in place and then get the hook back down to lift up the next section in 20 minutes." "Over 500 tons of steel is installed in nearly 100 separate lifts." "The Shard was really gonna hit the absolute limit of how high you could build in London." "With the building at its full height, designers can finally begin to visualize the monumental shard." "40 floors of steel house almost 600,000 square feet of office space." "For the hotel and residential accommodations, concrete is used to enhance acoustics and limit the building's sway." "¶¶" "Safety is a top priority for the builders and engineers of the Shard." "We know from previous fires in tall buildings that it's a real challenge to get people out of the building safely." "And that's an absolute focus to engineers working on tall buildings like this." "To ensure the Shard's inhabitants are safe if there is a fire, its designers need to draw on an innovation that's over 100 years old." "Professor Luke Bisby is in Edinburgh, Scotland, recreating an engineering marvel that changed the face of building safety around the world." "Now, it might be difficult for many of us today to recognize that fire was once a very serious and everyday threat to our homes and businesses." "Heating and lighting were both largely reliant on open flame." "And, in combination with the fact that many of our buildings were made largely from wood, this is obviously not the best combination." "In 1874, Connecticut businessman Henry Parmelee developed a system that helped combat the threat of fire." "With inefficient fire extinguishers, factories in many U.S. cities were burning to the ground." "Insurance costs were skyrocketing." "Parmelee was determined to control the premiums on his piano factory, so he came up with an ingenuous form of fire prevention." "So what we're gonna do here is try to recreate a simplified version of Parmelee's invention." "So what I'm gonna do is I'm gonna start a small fire here." "Any fire in a building is a bad situation." "And fires are particularly a problem in industrial buildings of the type that Parmelee was using because, if you have a localized fire such as this one, that fire can then spread to other flammable contents of the building." "During evening and even some daytime shifts, many areas of Parmelee's factory were unattended, so human detection wasn't a reliable solution." "So the problem that Parmelee faced was, how do you detect a fire and then put that fire out if there's nobody around?" "So the solution that Parmelee came up with is actually here next to me." "And the really critical piece is this little cap right here." "And what I have here is a little, metal valve." "And, on the underside of the valve," "I have a secondary piece of metal." "And we've attached that in this demonstration just with some wax." "Now, Parmelee actually used a low-temperature-melting alloy." "What I now have is essentially a valve on the bottom of this pipe that is temperature sensitive." "And so the system that Parmelee had invented basically consisted of a reservoir of water." "That reservoir is connected through a hole in its base to this copper pipe." "That copper pipe runs across and down to the valve that Parmelee had created." "Now, let's see what happens when we introduce fire into our system." "And, as I do that, the valve gets warm, and the wax that is holding the plate in place should release the copper plate." "And the valve almost instantaneously, sensitive to the temperature, releases water down onto my fire." "And so what Parmelee had invented was really the world's first automatic fire suppression system that both detects and reacts to a fire very quickly." "Parmelee called his invention the automatic fire extinguisher." "It was rapidly adopted in the U.S. and Europe." "His game-changing piece of engineering paved the way for modern sprinkler systems around the world." "Engineers at the Shard are taking Parmelee's automatic fire extinguisher to the next level." "They're incorporating one of the world's most advanced fire suppression systems into their mega structure." "The sprinkler system is all centrally controlled by a building management system." "Total fire engineering control here, getting the water around the building to where the fire is likely to be." "Driven by 200 kilowatt motors, two mega pumps feed water to seven sprinkler zones." "Three pumping stations are located at different levels, insuring even pressure for the building's hydrants." "Access for firefighters is via three shafts." "Each includes stairs and a fire elevator, allowing occupants to leave by the same means." "This is one of the first buildings where people can use the lifts rather than just the stairs when being evacuated in fires." "¶¶" "The designers of the Shard are pushing the limits of architecture." "To build this audacious structure required, literally, acres of glass, 56,000 square meters, which is equivalent to nearly eight football fields." "Their goal is to make the Shard the most beautiful structure on the London skyline." "The Shard in central London is rewriting the engineering rule book." "Its 73 stories are a mind-blowing sight." "This jaw-dropping tower is over three times the height of the statue of Liberty." "Its facade is made out of a staggering 11,000 glass panels." "That's enough glass to cover 130 basketball courts." "Beneath the 196-foot spire lies the spine of the building." "The colossal concrete core supports 72 levels, totaling over a million square feet of floor space." "It's just incredible." "It's this audacious piece of architecture, a splinter of crystal bursting out of the earth." "And, amongst this grand center of London, all these different buildings, the Shard just towers above all of them." "For structural engineer David knight, its stunning looks come down to one material that appears to rise straight out of the river Thames." "Look at the crazy amounts of glass that this building uses, 11,000 separate pieces." "It's extraordinary." "It just extends above me in a great, big ribbon of glass up to the sky." "To build this audacious structure, required literally acres of glass," "56,000 square meters, which is equivalent to nearly eight football fields." "But glass is weak." "So how do you create London's tallest building out of it?" "It would be impossible without some inspiration from an architectural risk taken 150 years ago." "Engineer Dr. Rhys Morgan is in the city of Liverpool in the U.K." "To see the building that holds the secret to modern skyscraper design." "In the 19th century, as cities like Liverpool grew ever more dense and space for buildings became smaller, architects were faced with a real problem." "They had to build upwards, but, in doing so, they had to build thicker and thicker walls to support the increasing weight of their structures." "So they needed a new engineering solution." "Local architect Peter Ellis provided the answer." "He came up with a revolutionary design for his high-rise building." "This is the oriel chambers building, tucked away in Liverpool's financial district." "And, although a relatively unassuming building, it contains one of the world's most important engineering and architectural blueprints." "In 1864, U.K. Architect Peter Ellis designed a structure which holds the key to modern skyscraper design." "This is the oriel chambers building, tucked away in Liverpool's financial district." "And, although a relatively unassuming building, it contains one of the world's most important engineering and architectural blueprints." "The oriel chambers building doesn't need exterior supporting walls." "An iron framework carries the load of the structure on the inside." "This allowed Ellis to create a facade on the outside that doesn't have to support the building." "Ellis' iron frame structure not only carried the weight and provided structural stability, but it also opened up a whole new world of architectural possibilities." "Walls could be thinner and lighter." "Previously unimaginable amounts of glass could cover the building's exterior." "Ellis created the glass curtain wall." "In 1864, it was a really radical idea." "And Ellis was criticized by his contemporaries for creating an architectural aberration." "Architects may have been skeptical, but developers saw the potential." "The building has 56 road-facing bay windows over five floors." "The windows flood the interior with light, creating premium office space." "150 years later, the benefits are still clear." "It would've been a real luxury to work in here with the abundance of light coming in through these bay windows or oriel windows, as they're properly called." "And, to compare it with the building across the street where the stone construction means the windows are very small, this would've been an amazing place to work in because of the light coming in from all directions." "And you also didn't have to use electricity to use lighting in the wintertime, a real advanced idea for the 19th century." "The fact that these chambers were built in 1864, over 150 years ago, makes it one of the world's first examples of a glass curtain wall installed on a multi-story office building." "And to think that he was derided for it and was so far ahead of his time is quite extraordinary." "Ellis' groundbreaking work on the chambers building has inspired American architects for centuries..." "And is still shaping the skylines of the world's greatest cities." "It's incredible to think that, without Ellis' pioneering use of the curtain wall concept, the glass-clad super towers of today, which dominate cities across the world, might not ever have been invented." "It's a real masterpiece of engineering." "Engineers at the Shard are building on Ellis' glass curtain wall to create their own one-of-a-kind structure." "13 acres of glass cover the Shard." "What's incredible is that, from outside the Shard, it looks like it's a structure made entirely of glass." "But, actually, this glass takes none of the weight." "That's all borne by the steel and the concrete structure inside." "An incredible piece of engineering." "The steel and the concrete makes the building stand up." "That's provides the strength and the stiffness, stops it swaying about, supports all the loads." "And one of the loads it supports is the weight of the cladding, the weight of the glass." "Unlike the rectangular oriel chambers building, the Shard's extraordinary super structure allows its designers to hang eight sloping facades, defined by the tower's iconic vertical fractures." "It's often called the Shard of glass." "And the idea was to have a beacon here that would shine out." "And this sloping shape is very good at reflecting the sunlight and making it shine." "Creating a vision of glass on this scale calls for extraordinary measures never before attempted in London." "The steel super structure of the building is enveloped by 11,000 panels of glass, each of them weighing 300 kilograms." "And the only way to install them was for each of them to be installed individually by a specialist engineer." "And looking at it from up here, you can see that's not a job for the faint-hearted." "The final glass section is fitted, signifying a milestone for the Shard." "It is good to be at the cutting edge and driving things forward and doing stuff that's never been done before." "This seemingly impossible architectural achievement took less than 4 years from breaking ground to grand opening." "It's the result of brilliant planning, design and testing by hundreds of engineers." "I'm personally excited because I see symbols of London that now include the Shard." "It's very exciting to be involved with something like this." "This is, uh, it's a one-off." "It's a once-in-a-lifetime achievement." "By learning from the great pioneers of the past, adapting, upscaling, and making innovations of their own, engineers have changed the face of skyscraper design forever." "The Shard isn't just an amazing piece of engineering, but it's captured the public imagination too, become a tourist attraction in its own right." "And that surely is amongst its greatest achievements." "The creators of the Shard have succeeded in making the impossible possible."