字幕表 動画を再生する 英語字幕をプリント from the waters in the Yangtze River in China rises the biggest concrete structure a plan the Three Gorges Dam is over two kilometers long and 60 stories tool it has taken forty thousand workers over 70 years to build when it fully comes online this one down will produce over 20,000 megawatts how twice as much as cool the nuclear power stations in Britain put together it is the pinnacle damn engineering home the Three Gorges Dam owes its success to 5 landmark times in the heart it leaves lies a major technological innovation allowed engineers to build and big data one by one traveling up the scale will reveal the incredible stories behind the structure on and the inventions that allowed them to produce evermore power 6 ingeniously forward from being to bigger into the world things I'm here I'm them I'm China is one fastest-growing economies on to fuel the need to mix ever accelerating industry nation needs more much in this would be provided by an enormous down spanning the mighty Yangtze River in central China called the Three Gorges our cameras have been granted privileged access to capture this amazing feat of engineering in its full glory the before they could start building 3 largest the Chinese first had to divert the Yangtze River which is almost two kilometers wide and move over a million people from the area about to be flood Three Gorges Dam is the biggest hydro-electric project in the world this damn news 28 million cubic meters a cock maybe one way to look who's to say saw solid hyper concrete a meter diameter right around the world lot a concrete the chinese authorities think it's worth the effort as the Three Gorges Dam will provide clean and cheap electric power to millions to understand how the Three Gorges Dam can produce so much we need to travel back in time to nineteenth-century Britain and a modest stream in Northumberland the power behind the world's first hydroelectric dam in the eighteen hundreds while Britain is at the heart of the Industrial Revolution this house is the last word in modern lived it belongs to Lord Armstrong an entrepreneur and obsessive invent he has fitted his house with state-of-the-art technology including central heating and mechanical devices that drive elevators laundry machines and roasting space but there is one place in the house where modern technology is sadly lacking as historian and Tony Burke explains this was Armstrong's real pride and joy the picture gallery for wonderful Victorian paintings bit gloomy even in daylight what he really wanted to do was to bring his guests here in the evening by the flicker candle light nothing really worked what Armstrong needs our electric lights and away to power them how do you generate electricity that something was known for fifty years was Michael Faraday a given the secret you move a magnet in relation to call on work bundle set appear so how it might work now here we are here we've got to magnets on the end this disc and right here is a call love one now if I make this spin mission to that we should make electricity on yet getting reading on a meter we are definitely taking elect every time the magnet some this moved past oil generated tiny electric handsome copper wire make a lot of electricity you need much bigger Kate and this is what Armstrong board Thomson vortex turbine agran peace equipment the thompson turbine needs a huge volume of fast-flowing water to drive the road Lord Armstrong has available is a tiny stream trickling through his estate what he needed was this a lotta water hud's again this on a small stream a built a dam mom Armstrong builds and Perth wall nearly ten meters high which turns history into a deeply this massive water pushing down increases the pressure at the moment Armstrong channels this high pressure water down through a pipe to the bottom now he injected into a Thomson to her by with Tara spins the world this in turn road takes a shot lead to a generator the produces four thousand wats electricity for Armstrong this is only the first step to enlightenment now he needs to get the electricity from the turbine house at the bottom it is Dom all the way to his picture gallery over a kilometer away Armstrong connect two strands of the copper wire to the generator to carry the electricity up to as much all in all uses five tons of copper to power a single like gold but he has created a world-first house let's by the power above water ok on the other side of the planet in central China the Three Gorges Dam takes Lord Armstrong's concept to the extreme British engineer Robin Charlwood has been working on the time since 2003 and is still impressed by its scale wherein wanna 3 very large powerhouse Three Gorges Project in this seven hundred meter long from here you can see 40 large turbine generators then me on this one kilometer away second house then be on that one yet another powerhouse to be underground at the Rock the Bogside their each one of these generators cost about $50 million dollars good idea at this scale this project damn damn damn have one generator Three Gorges has 32 together they produced by million times more power than them to drive them the chinese have harnessed the power the mighty Yangtze River in the reservoir behind the dam the river now rises up to 60 stories about river water is channeled down gigantic concrete choose to walk the generators here the torrent water hits the turbines and makes spent this motion is in turn transferred to the rotary general this is fitted with a massive magnets which moved past copper coils in the casing to generate electricity just wanna these machines makes as much electricity as a small nuclear power plant 132 generators together produced enough power for $60 million Chinese this project is setting a new benchmark in the international hydro-electric industry it's almost twice the size of the next largest project it out Brazil cause is only the first a whole series that make it at are under construction here in China back in 1878 dead and I'm showed that even the smallest dream can be harnessed to produce electricity but to generate power on a larger scale engineers had to wrestle with bigger returns to build a dam that could produce a 128 make once French engineers had to persuade the raging Dordogne river to run courts France in 1940 the outbreak of the First World War plunged the country into a deep energy crisis with that cold feels occupied by the germans the French are forced to import coal from abroad to feed their power plants and keep the country going so after the war they decide to boost the nation's power supply with electricity from a hydro-electric dam but building a concrete dam in the fast-flowing Dordogne river presents quite a challenge and this is all a mighty river Dordogne here on the beach now you call just Paul concrete in the Middle River they wanted their damn here but not to get one damn they had to build three for civil a temperate damn goes in here what's called a copper damn that stops the river flowing be cut to stop it is gonna go over the top unless you do something different bill a diversion channel right round at and then to stop it backing back up again you put in a second cofferdam he annual spacing between which you can drain and its there you can build your main damn at the door died engineers blasts two tunnels through the rock to carry the diverted river they drop steel cages containing rocks into the river to make that temporary coffered up then they strengthen it with concrete now is the river behind the dam begins to rise it drains through the tunnel to stop this water from backing up the engine is built a second cofferdam once the water drains from the river bed between the dams it leaves a perfect Dreisbach to build remains was completely engineers discovered when the into the central part that actually the riverbed was solid will good bills straighten top layer by layer giant concrete structure rises 30 stories up from the river the engineers then close the diversion tunnels and allow the reservoir to fill up and submerge the coffer dams their job done finally they can open the gates to the turbines and stop producing Tricity when the Marais aged I'm is finished it produces a 128 megawatts enough to help power train line to only all and supply the city of Paris 400 kilometers away with electricity the Yangtze River is over 6,000 kilometers long and in places several kilometers wide the biggest River in China it presents enormous logistical challenges to the dam engineers as the Yangtze rises behind the Three Gorges Dam it will flood over a hundred and fifty thousand acres of land along its banks so the chinese have to relocate over a million people from the land behind the time thousands of new houses have to be built for the displaced citizens to live it then the engineers can begin damn River wrist and here among some in the rocks and these precast concrete blocks that were used to tree the coffer dams to control a river during the construction the Three Gorges Project controlling the river to allow the construction of this huge project was clearly a major undertaking and with the Yangtze rivers 1 largest rivers in the world very fast very deep so building is confidant's and to allow safe construction was a major operation the Chinese claim that this was the largest most difficult diversion ever undertaken for hydro-electric project I'm you look at the scale of it they were absolutely right this was huge you the engine is begin work on a series of stone cofferdam to block off part of the axe was leaving a channel open for the rest in the river to flow through they build the first two sections of the main down on the drive reverb then they dump tons of earth into the river and on top of it build another cofferdam this time from concrete with the river held in check behind its they can finally bill the last section at the bath then they must remove the cofferdam so that water can flow through the turbines and the main to having built such substantial cover them structures it's a major challenge how to remove these things so in the in the earliest stages where they were built to very large rocks like this then that could be handled with big X greater equipment relatively conventional but in the final stage where they had a solid concrete wall to remove this required some serious innovation up unlike the cofferdam in my rage the Chinese version is Jim told to simply leave it in place so the Chinese engineers build it leaving holes for explosive charges on the 6th June 2006 they fill them with 290 tons dynamite and hold their breath up what has taken months to build takes only seconds to destroy as the cofferdam crumbles and unleashes the water stored behind you it's the final test for the Three Gorges Dam and it holds back in 1935 them are aged I'm proved that engineers could divert rivers to build powerful downs but to break through the 1000 megawatt American engineers building the Hoover Dam had to take that building material to the limit in the 1930s USA decide to tackle one of their big economic problems the cities in the western United States can't grow because they lack both water and so to break the deadlock engineers begin work on the world's biggest dan the from people who worked on real adventurous these guys high sky I would say on a plaque hung from a row of the top of the cliff and I would go along with hydraulic hammers basically smashing out cliff place so that when you pour the concrete up to it would fit together well they poured more concrete on this damn then on any other construction projects before but managing so much concrete can be a big headache for a damage near when you doing really big concrete poles is a very particular problem that problem is hate the first thing you have to understand is that concrete is made up to three basic ingredients first ball you have this stuff which is cement now that's the active ingredient that's what reaction changes you have water which reacts with the cement and have this stuff down here which is aggregate which is basically style this case at hand which gives the whole mixes strange now when we put this cement in here what we're gonna have is a chemical reaction hydration reaction in fact and its except for Nick which means that the temperature this lot should rise Solis and the test and see if we write we can see it rising there and it's already gone up to 15 degrees C and if we wait around little while longer I'll go up some more what we've seen a is that we do get temperature rises not much but actually when you're in the middle of a great big concrete pole hate has got nowhere to go and so the inside lump of concrete gets hotter and hotter and hotter and expands when expands it cracked the concrete is on the outside a bit and if you're doing a big concrete porn and dad cracks or a bad thing up if the concrete at the Hoover Dam is poured in one go the concrete on the outside world cool and harden first while in the core of the dow the concrete stays hot and tries to expand this could stress the concrete and make crime all so the engineers cast the concrete for the Hoover Dam in small individual blocks as the concrete in each block schools it shrinks but it doesn't crap the contraction leave small gaps between the blocks which engineers must filled with cement up but this clever design doesn't solve all the problems when who the time is enormous mean there's six million tonnes concrete who the debt and if we were able to concentrate all over the haiti is generated by that curing concrete into a single oven we could cook half a million loans have bred every day three years this structure if that was left on its own I think it's gonna take a hundred and twenty-five years for it to finish shrinking cooling down basically that's not nearly quick enough a guy in charge if a local Frank Crowe they callin hurry up kroger is a man in a Colorado River to call my dad on grow embeds over 950 kilometers steel water pipes into the concrete the damage well he builds a huge water chilling factory here he Kuils River watered down to four degrees and then shoot it through the pipes into the hard concrete on I'm this shortens the cooling time from a hundred and twenty-five years to only 22 months now this works a tree all have to do is finish the dan cement grout up the pipes and they're out there fantastic effort actually took five thousand men only twenty-one months to build the structure not only that they finish two years ahead of time and they finish had a budget the Hoover Dam stores $35 billion cubic meters of water and that the time generate more power than any other dam in the world with this magnificent damn behind them the cities in the American West can finally begin to thrive ok the Three Gorges Dam takes concrete construction to new heights look at it you can just picture that fitness is a concrete base in the damn the hydrant 180 meters minutes two kilometers long so it's a colossal amount cock Three Gorges uses ten times more concrete the Hoover Dam so the engineers have to pull out all the stops to keep their damn cool made rescue use everything in the book be cool D I its materials the sands before they put into the mix they added ice they did everything they could to get the temperature down as low as they could for it starts to warm up for myself and here because the issue some other summer weather being specially hardened July holders they actually went so far as to user fog spray system to blow affectively a fog blankets over-the-top damn with the objective blocking this on a radiation from hi down into the concrete and heading to the it was being generated on the inside back in 1936 that move a damp proof that engineers could build impossibly big concrete dams as long as they can cool but as dams grew they held back ever more water and with it tremendous destructive power to build the grand coup leader American engineers to protect from a catastrophic effects about flow johnstown pennsylvania 30 have made 1889 as the town gets it by the heaviest rainfall its history the tranquility the dam reservoir is about to be shot on it drains for 24 hours and the water reaches the top done soon it has nowhere to go but over the top the dam fails and 20 million tons of water empties in 45 lemme a water water 80 meters high crashes down the valley and it's John's utter destruction and shoes the new over 2,200 lives are lost in the flood I'll it is the worst disaster the US as ever seen why do dams burst when they overflow engineer Ed McCann explains now a particular problem is when water flows over the top and weakens all with the grass the ground in front here very vulnerable to single time scale and we're gonna have a go modeling to see if we can see what happens with toes curl this is our flood coming along in our river and fills up behind the dam right up at the top here now and the wall soon start pushing over the top in coming down and it will fall down this place and scour Wayland MA in you can see the damn starting to move already as the ground in front of his lost the damn loses its foundation begins to rotate over they won't be too long before it goes all together and back which is a reasonably satisfactory dam failure when it goes we get a tremendous wall water come down the valley and if you happen to be down there you're probably dead where you can see that time Skyrim this old dam is a huge potential problem it's something that absolutely has to be fixed ok in 1933 American engineers start work on the ground coup leader across the Columbia River in the northwest America a damn that dwarfs even the Hoover Dam it needs three times more concrete and spans three times the distance as the engineers complete the grand cooley they have to make sure that what happened in Johnstown won't happen here ok water rushing over the damn could quickly erode the riverbed and cause disaster so the engineers form the box move the damn into a concrete run ok this sense the water shooting down the spillway into a tumbling cortex which dissipates an edge as the water cascades of the ramp it loses much of its destructive power with the ramp in place engineers can safely run the largest hydro-electric dam in the US a title that the grand cooley dam retains to this day just ok the builders have the Three Gorges Dam face a similar problem they too must make sure that their dad is not damaged by flood water rushing through basically the damn hold back large volume with the water during the flood period here can hold back about 22 billion cubic meters of water and then its release in a controlled way through this system forty-six spillway gates and these shoes you can see below me here the design them a spillway like this has the deal with the force of the water as the drops over a hundred meters in this case here then achieve shoes velocity at the bottom with the damn to deflect the force of the water crashing down the Chinese use technology similar to the ground coolly one as the water levels rise engineers open a series in gates to drain the flood water from the reservoir but if the water fell straight down could undermine the foundations so the engine is fit the spillway with concrete shoes unlike the grand cooley RAM which is underwater the Three Gorges shoots pearl the water into the air once airborne the water breaks up into small droplets and loses much of its destructive energy it lands over a hundred meters downstream where it can't do any damage so now when they open a spillway gates the Chinese have nothing to worry about back in nineteen forty to the grand cooley showed how dams could deal with the abrasive power flood but to build a dam across the mighty Genesee River Russia engineers had to find a way to stop the water while keeping the ship's movie in the 1960s the Soviet Union wanted to upscale its industrial power so they plan a series of gigantic dams I'm one of the first the Crocs not ask Dan will stretch a whole Colomb into across the river Yannis E and generate 6,000 megawatts of power but this river is also the main shipping to siberia and would get blocked by to to keep the ships moving engineers hatch an ingenious plan they will build a steel trough big enough to carry shit then they will push trough and ship up to the top of the time here they will spend the whole contraption round and lower it back down to the river on the upside to move the seven thousand load they will use hydraulic pumps engineer Ed McCann employs a hot water bottle to demonstrate the principle behind hydraulic power right connected to my hot water bowl is a is a pipe which goes into this garden hose disconnected up to this wat care let's see what happens on lifted up by about about that meter some left it up to me to and the pressure in this system has gone up but it's not gonna enough to lift this year so there's no movement hot wall but we still squashed flat on the stand back a satellite blocks on the head some lifting up it's about three meters now you can see the concrete blocks moving very quickly now take it right to talk shit about 4 meters ago but you can see there is the amazing power force you can get out water under pressure that will be used to lift big heavy stuff the russian engineers use liquid under pressure to lift shins in the walls of the chamber a powerful pumps which squeeze hydraulic fluid under immense pressure into a set of motors mounted below up these drive huge deal clogs the propel the trough along guide the motors generates so much traction that they left the chamber from river to reservoir in only 19 minutes when the ship left is open the citizens have crews now ask turn out in droves this mechanical marvel is the crowning glory the biggest diamond work car China's Three Gorges Dam the engineers also face a major traffic problems their damn said some one of the busiest rivers in Asia the Yangtze is a really important waterway or navigation traffic in china the alway from Shanghai the coast the chain or eat it wrong it's been carrying about 18 million pounds and freight per year getting about a hundred and seventy ships day over a damn that's more than a hundred meters high is a tool order for the engineers befitting the biggest down on earth the Chinese solve it by building the biggest ship block on ships enter the lock at the bottom of the pan gates close water floods in and lifts the ship's of the next ships must go through 5t is a blocks to get to the top which can take up to four hours this is fine for cargo ships but for the many passenger boats operating on the Yangtze it's just too slow to provide a more efficient transit opportunity for passenger traffic they've built this shiftless system here which allow boats to go through in about 36 minutes unlike the ship left it cause may ask the one at the Three Gorges will lift ship straight up like an elevator and the secretive its success life hit in its concrete wall ok the engineers will fit a series of massive counterweights that will do most lifting 16 1,000 tonne concrete blocks will be connected by cables to the steel trough that will carry the ship and the water and floats as the counterweights drawn they will placed the trough upwards and left the ship to the top home this ship left here is 130 meters hi and can handle vessels up to three thousand tonnes you make it largest in the world twice the size the one across 10 certainly when you look at the structure now it's got a ways to go terms and construction won't be finished till 2050 but its it's clearly huge some another very impressive achievement on the way here after a hundred and thirty years innovation dams have produced ever more power today there is hardly a former energy that is as clean as hydroelectric power but as dams grow bigger so does their impact on the environment in their design the Three Gorges Dam Chinese engineers have to make sure that their structure doesn't completely blow nature's way of feeding line the Three Gorges Dam produces more power than any other but that's not the main reason with bill the Yangtze River is notorious for its really severe flooding over the last two thousand years as being about one major flood every 10 years in 1931 there was a really bad one killed about 235,000 people destroyed almost two million homes and so that this is the main reason why the built three gorges dam is to control this terrible flooding problem the dam blocks the path the destructive flood water the water is stored in its reservoir and is then released in a controlled way the managing floodwater can also have serious environmental side effects as recent history show in nineteen seventy Egyptian engineers build the as one Hyde damn across the River Nile to control flooding but soon farmers downstream notice that their harvests are beginning to fail this soil becomes so barren the farmers need millions of tons of fertilizer every year to nourish their crops their land has suffered because it has been deprived of floodwater which carries with it the vital building blocks life chemist doctor Andrew should look demonstrates so we have here are clean rainwater which has been falling we adding to its in good quality topsoil we then some animal extra months we have some snail shells essentially made of calcium carbonate then we have some drive leaves clock widget Asian here and of course fish as the store proceeds as the water starts to flow rapidly all these ingredients get mash top in the hugely violent storm waters which occur so here we have it a veritable cocktail mother nature's most important plant nutrients nitrogen force for us counts %um magnesium and potassium but if floodwaters stops flowing these nutritious particles of silt will begin to settle this is a big problem especially in the biggest damn 1 the flow of pressures yangtze silt is blocked by the dow and trapped in the slow-moving rest it rapidly sinks to the bottom word built up sorting problem the Yanks is a huge problem total amount coming down it's about 500 million tons per year which equates to about one kilometer cue absent after Phil big sports stadiums hundreds of times it's a huge boobs if this silt remains trapped behind the day it would mean the farmers fishermen and wildlife would be deprived nutrients in the water the hundreds of miles downstream home and the tons have settled silt sentiment could build up in the reservoir and threatened the damage cell base sediment falling into the reservoir here with reduce the the capacity the reservoir capacity in but eventually perhaps interfere with the ability to run the turbine suppliers came up cleverly the Chinese engineers exploit the power Lord flush the sediment out to the reservoir and send it downstream they installed sluice gates deep inside the bat each gateways as much as a bus and needs a powerful hydraulic piston to lift it up when the operators open the games floodwater rushes over the trap sediment and sweep through the dam gold this way the chinese authorities hope that it will be at least another 100 years before the buildup of sentiment affect power production the time good even the clever purging system cannot carry all the sentiment across the damn scientific estimates on how much sentiment remains behind vary from as little as 30 percent to as much as 60 percent the chinese authorities believe that this is a price worth paying they are convinced that the benefits and the damn such as clean energy flood control far outweigh significant drawbacks as the Three Gorges Project draws to completion its scale is breathtaking even with some with its turbines still to be switched on it produces more power than any other time in the world standing on the shoulders of historic engineering Giants the Three Gorges really is ultimate hydro-electric dam until someone builds an even bigger
B2 中上級 ナショナルジオグラフィックビッグ、ビッグ、ビッグ、ビッグ:ダムS02E08 (National Geographic: Big,Bigger,Biggest:Dam S02E08) 1434 63 Jason に公開 2021 年 01 月 14 日 シェア シェア 保存 報告 動画の中の単語