Tallest Buildings and Constructions in the World | Masters of Engineering | Free Documentary

[Music] today the world has three mega skyscrapers reaching over 600 meters physical representations of man's eternal desire to conquer the sky from the tower of babel to the burj khalifa in dubai the creation of high-rise constructions has been unceasing [Music] richard taye is a physicist he went around the world to research the subject asking the expertise of engineers and scientists driven by their desire to reach for the sky [Music] how were the egyptians able to build pyramids that dominated the world for nearly four millennia what were the methods of cathedral builders how did engineers make use of scientific models to design emblematic monuments richard taye takes us on a vertical journey in the footsteps of those who set out to conquer the sky to understand how over the centuries men have been able to defy and then master the laws of physics as they build higher and higher [Music] his investigation of man's race for elevation took richard taye to egypt [Music] at the edge of cairo on the giza plateau stand the pyramids [Music] the pyramid of khufu the largest remain the tallest structure in the world for nearly four millennia what expertise was available to the egyptians when they built these monuments it's a mystery that continues to fascinate scientists and egyptologists such as pia tales with him richard taye visited the pyramids the last remaining monument of the seven wonders of the world hello mr telly hello so thank you for meeting me here to help me understand the pyramids it's my first time seeing them in real life can you tell me a little bit more about what we see here these are the three pyramids of giza the most famous pyramids they're in chronological order the pyramid of kufu which is the farthest then cafe and finally the last one which is much smaller mencor they were built around 2500 bc and how tall is the tallest the tallest kufu is over 146 meters high a height never reached by any subsequent pyramid what's really amazing is its steep slope it must be a 45 degree angle the khufu has a 51 degree slope with a base of 230 meters so it's very steep and we're a little bit far away but even from here i can see that the blocks are huge how did they move them do we know the question of the physical construction of these pyramids remains open for debate archaeologists believe there were different models of ramps that would have allowed the blocks to be transported these ramps were used with sleds so an inclined plane was used to raise the blocks they're heavy two and a half tons on average really and it is estimated that for the largest of these pyramids kufu it would have taken about 2.3 million blocks to build the whole monument should we take a closer look of course when observing the pyramids all in a row a striking detail appears their slopes are parallel this is obviously not an accident but a mathematical concept proportion a case study examined by the historian of science evelyn baba on certain sites it's very easy to see that all the pyramids have the same slope you can see this just by noticing that the edges are parallel so it means that it was planned and we know how based on the idea of proportionality thanks to the rind papyrus we understand how the egyptians were able to build the pyramids so that their slopes were identical we know that the egyptians had the idea of proportion and used a small triangle using that small triangle told them where to place the next stone the small triangle and the pyramid with similar triangles as we say today and this similarity is found in all of the pyramid slopes [Music] how can we not wonder what methods were used to build these colossal stone constructions from the foot of the pyramid we can really see the blocks i mean they're huge [Music] people have an image in their head of armies of slaves working on the pyramids is this impression correct not really certain films have popularized the idea of slave people working on pyramids nothing is further from reality the more documents we find the more we realize that the work was remarkably well organized by the egyptian monarchy and that the workers were craftsmen chosen by the king they were well fed well-paid and employed on a yearly basis for their skills and according to the american archaeologist mark leonard since it took 2.3 million blocks to build the pyramid of khufu we can estimate that they made an average of 350 blocks a day over the 27 years of khufu's reign a team of 800 men is capable over such a long period 27 years of carving all the blocks that made up the pyramid by making these extrapolations we've concluded that a team of about five thousand at the most would have been perfectly sufficient to construct the entire building okay that's still quite a large team the pyramids dominated the world until the middle ages but it was on another continent in europe that the symbolic 150 meter bar would be crossed when church bell towers began reaching for the sky around the year 1000 christianity's development led to an architectural movement with romanesque art the desire for height was as much the expression of faith as a show of power but the race toward the skies advanced with the appearance of the gothic style with its broken arches in less than two centuries more than 80 cathedrals were built in france [Music] what challenges did the cathedral builders face what were their methods to find out richard taye went to notre dame damian a remarkable structure in many respects with the greatest interior volume of any french cathedral hello richard arnold nice to meet you so you're a medievalist historian engineer that's right i don't know if after all these years you're still as awestruck as i am but i find it amazing uh never fails to impress each time you look you always discover a detail you've never noticed [Music] so they started construction around 12 20. they began erecting a huge foundation of over seven meters high it covers the whole surface under our feet and then the nave was built very quickly all right advanced techniques we use to achieve this especially the advances brought about by medieval industry with serialization a sort of assembly line approach and you don't necessarily realize when you're inside but it's tall how high is it about 42.3 meters so 15 floors yes was a wildly ambitious project unrivaled at the time one that holds great fascination for [Music] richard [Music] as a physicist when i see the columns the mass that is above us i try to reason in terms of force and mechanics but i imagine that in the 13th century these notions were not very well known exactly what kind of theoretical tools did they have at the time for constructing these cathedrals in terms of theoretical tools they didn't have much mastery of the compass the set square the ruler very good drafting methods and the right materials they used the right stone in the right place empirically very empirically just by weighing the stone they knew its density and they put the heavier stones on the bottom the lighter ones on the top when we make sophisticated calculations today we realize that these structures are oversized from today's viewpoint because they didn't calculate the size at all but pillars like this could bear maybe 20 or 30 times the load they currently carry [Music] few or no theoretical tools as for the construction tools like the plumb line or the arithmetic rope they remain astonishingly simple in light of the scale and the complexity of these stone [Music] let's constructions one of these so-called rudimentary tools we're going to make a right angle with this rope that has 13 knots 13 knots we're going to make a triangle with one side that's three units one two three four units here one two three four era so if we calculate this on paper using geometry a triangle with these proportions should have a right angle here it's the pythagorean theorem but the medieval constructors didn't know this theorem however they knew that when a triangle has one side that's three units another four and another five it's a straight line so that gives us a right angle and it can also help to make horizontal lines [Music] if the vertical line here is aligned with this side it means at the bottom is horizontal yes let's try i'm a little intimidated it's my first time using this medieval tool here we go i'm putting it on the surface and yes it's horizontal it's remarkable so i tested the horizontality of this part of the cathedral the builders did a good job we can see that they managed to build something massive and durable using a relatively simple tool and then 800 years later with maintenance it has remained sound but not all cathedrals have been so lucky a few kilometers away san pia de bouvei has had a turbulent history it should have been the highest cathedral in the world but the builder's plans were foiled by the laws of physics leaving it unfinished officer who watches over it today [Music] so we're entering the cathedral at what should have been the main entrance if the nave had been built and we can see the size of the isle and the choir with its gothic architecture in front of us the bishop of bove who decided to rebuild the cathedral in 1225 wanted it to be the most magnificent tallest and largest cathedral in christendom so the vault is 48 meters 50 high the tallest vault ever built at the time sampia de bouve benefited from advanced technology it was reinforced with iron its arches were supported and bound together with metal tie rods but this precaution would prove insufficient the choir suffered some unforeseen events it was completed in 1270 50 years of construction and in 1284 some external flying buttresses broke causing certain arches to fall it didn't completely collapse but nevertheless as a precaution the reconstruction included a new column in each span and that's why it's a very small space so three new columns were added in between the 13th century columns all right each arch is therefore divided in two and supported by an additional column [Music] we're going to see the upper parts of the church now and look at the tie rods more closely the stairs are very steep here we are [Music] okay [Music] we have a good view here of the cathedral's 13th century architecture and the differences between the original structure and the reconstruction that took place in the 14th century so we can see this buttress column that is very streamlined but has a large surface area for the wind and then a column here in a cruciform shape that's a little less wide but offers protection in this direction it's really reinforced in all directions so more solid less wind vulnerability more stable yes more stable and if we move forward we see the structure of the tie rods the iron bars that criss-cross they're iron bars that connect everything so that the structure is held together if there's movement okay it keeps everything in place the continuity of the chain is the important thing one wouldn't be enough the evolution of gothic architecture with its unprecedented successes and spectacular catastrophes is studied in many universities including the united states richard taye headed to new york he went to meet with researchers from columbia university who are studying french cathedrals using modern scientific tools and have created an index of all of them [Music] stephen murray and rory o'neal have developed digital tools to better understand gothic architecture first off with a huge database called mapping gothic [Music] what's particularly interesting is here it's arranged by nave height but we can also arrange by approximate construction start here okay this shows the height so here we are in the year 1000 one can look at the heights of building changing and you don't see a huge amount of difference in them the great great breakthrough of all the cathedrals is notre dame de paris and it was the first building in northern europe that goes beyond 100 feet in height a and 1220 and here comes bove 12 25. why did it happen at that particular moment i would suggest the answer is not simple and what you're dealing with um is a period when the clergy the bishop are receiving huge amounts of money from agrarian production and industrial production in the cities and mercantile exchange so to make a building very tall like amia or broadway so in other words the technology was possible only because they had the resources to do it to experience in real time the challenges of the cathedral builders rory o'neal developed a digital simulation a sort of scientific construction game yeah the relevance here is to build an appreciation an intuitive sense of what the builders were uh challenged with uh they wouldn't be sure of how the blocks would behave until they put them up there and so we can put them up there more quickly in the simulation because each block is behaving as it would uh so we have the ability to vary the sizes of the blocks and their configuration in real time as we try to make this structure taller we've got the same outward force with this trying to fall and pushing these out but because these are taller it's got more leverage to push these things apart okay and so height the quest for height here is limited to some extent by the ability to vault the space so what we can do is certainly add more support on the sides more buttressing these holes and this hole okay but this is expensive here we've got a lot more stone has to be quarried it has to be brought to you well somewhere in islamic builders came upon the idea of breaking the arch a broken eye and whether or not this was done for aesthetic reasons or structural reasons we don't know however it does help it works because it's bringing the load more directly to the ground and certainly because of the structural benefits we can start going a little higher and try to make this taller and taller at some point this will also fail so everybody stand back so here we've got a failure of the structure in static loading but as we get larger to hold more congregants a growing city we need to come up with some other solution here what we know as flying buttresses so i think maybe even you could give it a try okay let's go it's richard's turn to try his hand at cathedral building and to experience the humbling challenges of the quest for height even seismic engineers today are still learning from these masonry structures because their simulations are not as accurate as the buildings themselves so for the most part seismic engineers are looking at these medieval masonry buildings to learn how to build better today [Music] for several centuries the race for height remained the domain of the sacred the highest cathedrals in the world om at 161 meters and cologne at 157 meters both in germany would only be completed in the 19th century [Music] at the beginning of the industrial revolution the concept of technical prowess surpassed that of religious will giving new momentum to the conquest for the sky the engineers performed what were miracles for that time exploiting new materials the steel industry was rapidly developing first iron and cast iron then steel would become the primary metals used in construction soon the first skyscrapers were born thanks to a tragic incident in 1871 chicago was a prosperous city of nearly a million inhabitants when what was later called the great fire broke out from october 8th to 10th flames ravaged the wooden buildings of nearly the entire city 300 people were killed and 100 000 left homeless as terrible as it was the episode paved the way for chicago's technological revolution since wooden buildings were now forbidden architects turned to new materials such as metal and so the first skyscraper was born the home insurance building designed by the architect william lebaron jenny he said that his goal was a height to rival the tower of babel but apart from the height it was the construction technique that was truly innovative in traditional masonry the load of the structure is supported by the walls the more height the greater the forces that are exerted hence the need to build thick walls for example a 16-story building in chicago has walls that are 1.8 meters thick at its base but thanks to the invention of the metallic structure buildings were able to become lighter and therefore higher [Music] traditional masonry was replaced by a skeleton of metal girders with the framework connected by rivets this supports the weight of the building and allows the entire structure to be lightened considerably [Music] thanks to this new technique man would be able to set new records in its conquest of height [Music] there was much new terrain to conquer and soon a rivalry began in the united states none of this would have been possible without a crucial invention the elevator alicia otis an engineer made the discovery around 1850. here it is the test tower to find out just how revolutionary his methods were richard taye went to the otis research center in connecticut 28th floor where he had a historical experience welcome ian venue bonjour merci richard i am wreck okay um you'll need to wear a hard hat okay safety glasses how do i look you're wonderful well i didn't expect to see a wooden device like this here so that's actually an elevator this is an actual lift in 1853 elevators were used for freight goods okay and if the rope broke the platform with the goods would fall damaging the materials being manufactured elijah otis who is the building engineer said there has to be a better way how can we prevent the platform from falling [Music] so if you look here you can see the spring that came from a wagon okay so he took something that already existed the mechanism that has been used in trains yes and what he developed was an ability to stop immediately the platform falling down if the rope broke would you like to try yeah let's go here there you go okay so let's raise the platform all right so that's pulled these two in [Music] okay here we are we say cut the rope the tension will be released it'll push the pawls into the ratchets and we're going to come to an immediate stop three two one cut the rope whoa yeah absolutely so in 1853 when elijah otis had his assistant cut the rope he docked his hat and said all safe gentlemen all safe four years after this impressive demonstration the first passengers would confidently ride in the elevator that alicia otis installed in new york elevators remain the subject of intense research today but they have allowed since their invention the true conquest of the sky to begin a bitter competition where science clashes with pride [Music] five years before the world's fair which was to mark the centenary of the french revolution gustave fell and his engineers had the idea for a 300-meter tower that would represent the country's rediscovered power and demonstrate its technical prowess [Music] hello museum one hello richard it's nice to meet you likewise so you're a specialist of the iron lady here's this beautiful tower shining under a blue sky on this clear and sunny day which brings out its graphic lines its lightness the structure is 300 meters high making it the tallest building in the world when it was built in 1889. it was really a visible marker of the technical and scientific accomplishment of the 19th century [Music] and how is the eiffel tower designed was it an idea that came from eiffel or was it a commission made for the exhibition the tower was conceived by two engineers emil negier and maurice kuclin who brought the idea for a 300 meter tower to eiffel in 1884 based on the bridge columns that the company already knew how to build this would of course be both the highlight of the universal exhibition of 1889 and also the great achievement of his career so now we're at the square under the columns we can see that they're leaning inwards how did it stand up before the first floor was built the challenge was to start the tower they began by building foundations and then the slanted columns to hold them up they just used wooden scaffolds the same that were used when building cathedrals the critical point was reaching the platform area on the first floor [Music] we shouldn't forget that they were assembling sheets of metal pierced with holes which had to be adjusted precisely before putting in the nails down to the millimeter from there it was a kind of giant mechanism that could be gradually assembled in less than two years the tower was built to everyone's surprise let's go and take a look from above let's go up we're in between the second and third floor about 250 meters high and we see that there's not much holding the top of the tower they're open work girders in total the tower weighs 7 500 tons it's very lightweight for a structure of 300 meters but it has been strategically designed to withstand the wind the wind creates pressure several hundred kilos per square meter which could topple the tower so they gave it a slightly curved form which causes the horizontal force of the wind to combine with the vertical force of the tower's weight giving a resulting force exactly in the axis of the columns so the shape doesn't come from the architect's imagination but from a mathematical calculation the shape comes from mathematics but that's what gives the tower its visual identity precisely because it's inspired by scientific studies and not by the classic rules of architectural composition okay from june 1889 visitors to the tower could safely reach the top thanks to elevators a real technical feat at the time [Music] here we go we're going all the way to the top from the second to the third floor we have an incredible panoramic view from here to 40 kilometers away it is stunning so in 1889 parisians could come here and see the very same view for the first time they had the chance to go up 300 meters in the sky and it was a real novelty and it wasn't just a small group of people who came but 2 million it was a very unusual opportunity they weren't familiar with mountains or altitude a lot of people must have had vertigo but it was also perhaps a way of warding off their fear saying to themselves i'm 300 meters high and i'm safe on this small platform it showed that one believed in the idea of progress which was strongly valued at the time by all of the citizens in any case i feel safe on this platform no problem i'm not afraid of falling [Music] on the other side of the atlantic with a dream of becoming the capital of the western world new york began its own race for height it started in 1894 with the manhattan life insurance building at 100 meters high the first real new york skyscraper in a long series that continues to this day [Music] what trials did the engineers overcome to erect these buildings what new techniques did they use richard taye explored new york along with historian mosette broderick and stopped at one of the city's iconic landmarks the flatiron building it's a very unusual shape it's a triangle it's where the bedrock of broadway meets the fashion of fifth and avenue of its funny location it got to be known as the flatiron building so it's a building that comes to a point like a ladies iron iron although we might call it a piece of cake yeah a very tall piece of cake but i guess it's not a piece of cake to build no no that was a nightmare for engineers to work on the problem they had was the site trying to get the flanges to work on this narrow corner but this is a skeleton steel construction with terra cotta fireproof design and cladding so this is a full skyscraper it has all the characteristics that are needed to make what we come to call after the 1880s a full skyscraper from the early 20th century every bank newspaper and insurance company wanted its own skyscraper it was a way of gaining exposure for their brand and asserting their reputation with a powerful symbol buildings of greater and greater heights sprung from the ground until one of them came to dominate the world for quite some time we're on fifth avenue 34th street is here and right up there is the empire state building the projected world tallest building for many decades [Music] wow what a beautiful lobby and what about this picture here oh this is wonderful a big image of the building itself there it is a building that sets back under the zoning law of 1916 in a very dramatic fashion in 1916 after 20 years of people arguing about how big these buildings are new york city passed a zoni law which basically says that the building starts with a base sets back at a certain mathematical formula goes up and allows people to still be bathed in light and not feel that they're down in an elevator shaft the empire state building with its distinctive silhouette is the ultimate model of the 1916 law and it was built at the frantic pace of four and a half floors per week it was a construction nightmare and you know it involved riveting huge girders in the middle of the sky looking out on nothing now i don't know whether you've ever seen them oh pictures of the construction workers the thought of it terrifies me but the special people who do it are mohawk indians from canada and they were able to get out on those girders and do it and this building was finished in 18 months it was finished may 1st the traditional moving day in new york city the building was ready on may day 1931 the building flopped that initial commercial failure did not however prevent the 381 meter high empire state building from remaining the tallest skyscraper in the world for four decades one of the defining features of the empire state building is that it is mainly constructed from concrete a 19th century innovation that gradually came to replace brick and terracotta this material made it possible to reach heights that were unimaginable even a few years prior along with steel concrete remains the primary material used in the construction of high-rise buildings today the higher a tower rises the more it is subject to external forces compression traction bending twisting and shearing exerted mostly by the weight of the structure on itself or by winds exceeding 200 kilometers per hour when subject to pressures that are too great towers can bend to one side swinging back and forth twist in on themselves and end up collapsing so they have to be constructed with materials that can absorb these movements when used alone concrete has considerable compression strength but its tensile strength is low steel is very resistant to traction and compression its physical and mechanical characteristics are the same in all directions it twists elastically until it breaks predictably always under the same conditions manufacturers had the idea of adding reinforcements to concrete in order to give it flexion strength so the tensile forces will be carried by the framework thus reinforced concrete was born to make it concrete is poured directly into molds containing steel bars the ladders support the concrete and allow it to effectively withstand the forces that act upon it [Music] thanks to the advances made in the strength of concrete and also lighter materials and increasingly efficient engineering the race for height gained new momentum in the 60s [Music] the united states popularized the skyscraper but the records they set were soon surpassed by asia and the middle east in asia shanghai singapore taiwan and kuala lumpur new high-rises were erected each day with hong kong holding the record with over 1 250 skyscrapers new records were constantly being set the number of skyscrapers grew exponentially it took 135 years to develop 50 super tall buildings and super tall we define as 300 meters or above and then the next 50 super told buildings happened in less than a decade so the pace of development is absolutely rapid and and massive however we were seeing such extremes of height that super tall no longer caught the essence of the extreme heights that we were seeing being proposed so that's why we introduced the term megatol which is 600 meters and above and right now there are three mega tall buildings complete around the world the final step of his investigation led richard taye to dubai here he visited the tallest building ever made by man the burj khalifa 828 meters of concrete steel and glass built in just six years what scientific model did the engineers use to design this emblematic monument this showcase of modern science richard taye received special permission to witness the internal workings of the skyscraper to discover its secrets obviously in such a large structure i'd imagine that the elevators must play a very important role definitely richer we have elevator which is the highest travel in the world 504 meters traveling so let's have this great unique experience traveling at 10 meter per second please be my guest [Music] this is a double deck so double deck elevator is like two cabin on top of each other this is the lower deck and we have the upper deck this one here this one here the lower one here correct so we're gonna take it up to the hundred and twenty third floor okay someone twerk please there are two buttons so slow closing button 123rd floor correct so we've been traveling around 442 meters i can feel the acceleration yes and the total travel takes around a minute until you reach for 442 meters [Music] i've never gone as high as 123 floors in my life [Music] please i'm starting thank you it took less than one minute to reach an altitude of 460 meters [Music] the highest skyscraper in the world is truly at the forefront of technology it is permanently under surveillance from an underground control room that richard taye visited this is the brain of our building the brain okay from here we get to manage and control and overlook all the operation of our equipment within burj khalifa all the systems that we have in burj khalifa are linked to these screens power supply air conditioning the structures movements a close eye is kept on every element to ensure the safety of this vertical city i'm especially interested in this one with the small oscillations is the world's tallest building and it is acting like a big sail and we need to always monitor its movement so what you see here is the actual building movement as we speak now as a physicist i'm interested because i see acceleration marked here so these are sensors that measure the acceleration of the tower i imagine you can convert this acceleration into motion into distance that is travelled beyond the equilibrium position yes the system has the capability to convert this into millimeters currently although it's a bit windy outside you can see there is a spikes here and that is in micron so it is hardly moving abortion of a millimeter it is that stay the building is that stable due to when the building can tolerate a building movement to approximately two meters to any direction building a skyscraper over 800 meters high that can guarantee the comfort and safety of its occupants is a technological achievement its designers had to find solutions to problems at up to that point had only been theoretical when you're designing these very tall towers the main load you have to contend with is wind it's not no dead load which is the weight of the building it's not live load which is the load of the people in the building and the furniture they put in [Applause] people don't realize when wind goes past an object and if that pulsing matches the natural harmonics of the building you get quite large forces one of our goals of shaping the building was to get the shape which confuses the wind and the shape of the building at the bottom you'll be going into two wings and by the time you get to the top it morphs into a nose like the front of a boat and through the shaping um the wind forces went way way down the unique layout of the burj khalifa allows it to divert wind but in structures with more classical shapes there is another way to resist movement even from earthquakes to limit oscillation these skyscrapers have dampers whose principle is simple it's a mass that moves mechanically to the frequency of the tower with a certain time delay thus helping to stabilize the building there are different kinds of dampers some are made from an enormous concrete block which must weigh at least 100 the mass of the building placed at the top of the tower on a layer of oil and connected to the walls by springs the mass follows the movement of the building but with a delay due to the oil in the case of the comcast center in philadelphia there is a hydraulic damper containing 1 100 tons of water that moves from one reservoir to another thanks to a motion sensor but one of the most surprising dampers is found at taipei 101 in taiwan a 508 meter high tower located in a seismic zone it's a gigantic steel pendulum measuring 5.5 meters in diameter weighing 660 tons which can sway up to 1.5 meters reducing the building's oscillation by 40 percent the wind was not the only difficulty the burj khalifa had to overcome with construction projects of this scope even when they're extremely well thought out there are always surprises in store and the most unexpected sprung from an unlikely source the building's own backers the initial design was only 10 meters taller than the world's tallest building at the time so it was only 518 meters tall but during the design process it grew by 310 meters the structure was already up at 35 floors the emar management heard that some other developers in the area were going to build another tower that was going to be higher than samurai meters so everything was kept very quiet but they instructed us to raise the tower height to 820 meters so we all came to the conclusion yes we can increase at 220 meters so the design was changed and um from that period we went on and finished the tower 120 minutes [Music] on january 4th 2010 dubai revealed a secret that had been fiercely guarded until then that the burj khalifa's final height would be 828 meters they celebrated the achievement with a spectacular inauguration everybody involved it was very proud and i can say you know a large measure of relief here it's like you know there's a big burden taking off your shoulders you can say wow i can relax now and now it's finished [Music] the burj khalifa is a skyscraper that has beaten all the records but if it holds the title of highest building in the world for the moment this will no doubt one day be stolen by another building already the kingdom tower which is expected to reach one kilometer is under construction in jeddah saudi arabia and if man strives to reach even greater heights will there be physical constraints insurmountable limits the only limit on height until we get to almost unimaginable heights like several miles stratosphere is financial there is no technological limit to height the quest for height means ego and attention mankind has this desire to go to the next level to push the limit and the quest for the world's tallest building has always been a part of that when you go hiking you want to go to the top of the hill to see what's in the other side you know you're walking down the street you want to see what's around the corner yeah uh and so this desire to go high is just it's somehow it's in our mythology it's just in our culture and why go climb a mountain well we do it's just part of part of being human at the end of his journey through space and time tracing the footsteps of those who set out to conquer height richard taye wonders since over the centuries science and engineering have allowed us to constantly push the boundaries of what's physically possible will nothing be able to limit man's eternal longing to reach for the sky [Music] [Music] you

Channel: Free Documentary

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Keywords: Free Documentary, Documentaries, Full documentary, HD documentary, documentary - topic, documentary (tv genre), engineering, engineering documentary, technology documentary, construction, tallest contructions, highest buildings, World's tallest Buildings, Tallest Buildings, burj khalifa, empire state building, pyramides, eifel tower, one world trade center, building comparison

Id: MCt6_eAiui0

Length: 52min 55sec (3175 seconds)

Published: Fri Feb 05 2021