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Building to Extremes
February 10th, 2004

Narrator: From ancient times to the 21st century, the human race has had a soaring ambition -- to link the earthbound world to the heavens with ever-taller buildings. From the Tower of Babel, to modern-day monuments of concrete and steel, tall buildings have defined cities and civilizations. They are enduring monuments to power and prosperity. Tangible records of ingenuity and towering declarations of our grand reach.

Cesar Pelli: They can become cosmic pillars--that is the incredible appeal that skyscrapers, like the Empire State, or the Chrysler Building, have generated for so many years.

Narrator: Then the unimaginable ... September 11th, 2001. Two jetliners struck the World Trade Center Towers. Two icons of a skyscraper-dominated city were reduced to rubble. Once-immutable skylines suddenly seemed vulnerable. The quest to reach the sky was called into doubt. Would 9-11 put an end to building tall? Or would developers and architects reaffirm their commitment to continue building to extremes?

For years, building developers have been trying to top one another -- steadily climbing upwards, and inching past the reigning champion. During most of the 20thcentury, the race for the sky was an American contest. In the spring of 1930, Walter Chrysler was dueling the Bank of Manhattan Trust Company for the title of world's tallest skyscraper. The two buildings were neck and neck -- until, at the last possible moment, Chrysler unveiled a spire that had been hidden in the elevator shaft of his building. The needle gave the Chrysler building the title of world's tallest by a mere 36 meters.

SOT: This is the tallest one this week ... but we do not know what tomorrow might bring.

Narrator: Chrysler's victory would indeed be short-lived. One year later, the Empire State Building was completed. It had a five and a half meter spire that the building's owners planned to use as a dirigible mooring line. The Empire State Building opened in May 1931 -- the tallest building in the world by 62 meters.

SOT: We're at the 86th floor of the Empire State building -- the top of this structure is the highest thing in the world today.

Narrator: At 368 meters, the Empire State Building would dominate the Manhattan skyline for forty-one years, until it was eclipsed by the 417-meter World Trade Center, in 1972. But the twin towers held the record for only two years before Chicago climbed 26 meters higher with the Sears Tower. Two decades passed ... and the race expanded overseas.

"Headphone voice in Observation Tower, first in French, then ... there's great national pride in the fact that the Petronas twin towers are the tallest buildings in the world ... ."

Narrator: April 13th, 1996. The Malaysian oil company Petronas puts its name and its country on the international map with two eighty-eight floor towers.

Cesar Pelli: It was the desire of the Prime Minister, Dr. Mahathi, that these buildings become a symbol of the city, Kuala Lumpur, a symbol of the country, Malaysia.

A. Eugene Kohn: What they wanted to do was to make a statement, they've arrived, they're part of the twenty-first century, that they're a great economic center.

Narrator: At 452 meters, they are just 10 meters taller than the Sears tower -- but by taking the title of the world's tallest building, they announce Kuala Lumpur's prominence as a commercial and cultural capital. Architect Cesar Pelli's winning design for the building, depicted two towers connected by a sky bridge.

Hashima Hashim: What the client wanted, is for the architect to incorporate Islamic characteristics into the building.

Cesar Pelli: During the competition and through the design, we were not seeking height, we were actually even totally unawares of how we were ranking and I couldn't have cared less.

Narrator: Despite Pelli's claim, he would incorporate a design element to reach higher than anyone before him.

Hashima Hashim: The Petronas Twin Towers has the spire which is about seventy meters so that adds on to the overall height, which makes them the tallest buildings in the world.

Cesar Pelli: In the competition we did not have the spires. The spires were very, very difficult to design, the difficulty, is that they tended to look like church towers. They grew taller and more svelte, until one day we realized, that we were within relatively few feet of overtaking the Sears Towers, and that gave us the impetus for the last push.

Narrator: In 1996, the Petronas Towers claimed the title of "world's tallest building." But Petronas would soon be challenged. The quest for the sky was about to become a full-fledged race.

August 1997 -- China. Japanese businessman Minoru Mori begins planning a super-tower in Shanghai, the country's second largest city, and a rapidly developing economic center. Mr. Mori hires New York architectural firm, Kohn Pedersen Fox for the design.

A. Eugene Kohn: And we are doing, what will be for maybe just a brief time, the world's tallest. And that's the Shanghai World Financial Center.

William Pedersen: Here we are designing, a building which will be inevitably a symbolic icon of Shanghai. And so we looked back to the ancient Chinese period when the symbols of the square prism and the circular disk seemed to take on a great importance for the relationship of the earth to the sky. And we did this by taking, essentially, a square prism, and then shaving off, with great sort of cosmic arcs, portions of that prism, such that the building then could translate from a square at its base to then, a much more delicate form on its upper levels.

Narrator: Like all tall buildings, the Shanghai tower will need to withstand high winds. To allow for the wind pressure, Pedersen comes up with a novel design for the top of the building.

William Pedersen: As we're getting up into those reaches where we have a broad and a narrow face we've introduced a large cylindrical opening in the top of the building, the circular moon gate to relieve those pressures.

Narrator: The "moon gate" addresses the wind problem, but the design causes an unexpected clash of cultures. The architects discover that a building in China, owned by a Japanese businessman, is a symbolic minefield.

William Pedersen: What I had, in my own mind, thought of as representing a moon gate, in fact, had been reversed in their own mind to represent the rising sun.

Leslie E. Robertson: As originally presented to Shanghai, the moon gate, this great hole was not very well appreciated because it was seen as an emblem of Japan. And the mayor of Shanghai was not the tiniest bit interested in, in, that.

William Pedersen: And I suggested the possibility of a bridge through the circular aperture, symbolizing the joining of two sides together, but at the same time to also tended to in a way diminish the power of the circular gesture.

Leslie E. Robertson: And that, that satisfied the mayor very well.

Narrator: Only one hundred miles away, that same year, another rival enters the race for the world's tallest skyscraper -- the Republic of Taiwan challenges mainland China with its own super-tower plans.

Harace Lin: I believe this building will increase Taipei's exposure and bring Taipei to the World.

Narrator: Originally, Taiwanese developer Harace Lin hired Taiwan's top architect, C.Y. Lee, to design a sixty-six floor tower and two smaller office buildings for a site in the capital. But the two men soon modify their plans ... and expand their ambitions.

C.P. Wang: Two key tenants were taking the two smaller buildings but then after they seeing the complex, they all like to be in the main building. We always wanted to build a very tall building, tallest building in the world and so when we had the opportunity to add the two smaller tower on the top and that -- the ideas already start growing.

C.Y. Lee: A Chinese architect, like me, I had the responsibility, you know, to deliver the message of Chinese, of China cultures into this buildings ... Usually, in the western world, you know, expression of the height is really strong pistol continuous to the sky. We will break, you know, the massing in incremental form to express the height, the more unit adding on, you know, the more height.

Narrator: Chinese numerology drives them high into the sky.

Harace Lin: We considered either 99 or 100 or 101 floors. In our Chinese philosophy 99 is a number that means forever, 100 means perfect but 101 means more than perfect. It also symbolizes innovation serves to remind us not to be complacent and to keep on improving.

Narrator: The building will have 101 floors ... and this new monolith, called Taipei 101, will be almost identical in height to the Shanghai World Financial Center. Neither team knows which skyscraper will ultimately take the title. The outcome will be decided by a few small meters, which makes the crown of the building critical to the contest.

C.Y. Lee: And then the question is what is the shape of the top so we spent a lot of effort so many different shapes and this is probably the best.

C. P. Wang: This is our beautiful pinnacle here ... sixty meters.

Narrator: But Taipei 101 has a long way to go before it becomes a reality. The transition from design to skyscraper is a difficult one -- and these architects have a rare problem. They are designing a building sited directly on an earthquake fault line.

Dennis C.K. Poon: For this project we have to deal with the high wind load, the seismic design requirements, and the soil condition, as well as the height of the tower and the unique shape all poses a challenge to us.

Narrator: So before their building can go up -- it must go down. Over 380 foundation pilings are driven into the bedrock, some 60 to 80 meters below ground. The pilings then undergo a dynamic stress test. Weight is added on top -- and an explosive charge is set off to simulate an earthquake tremor. The structure passes the test -- and by the summer of 2000, Harace Lin and his construction team celebrate the installation of the first of many massive steel columns. Taipei 101 begins its drive upwards. Its goal: The title of "world's tallest building." Meanwhile, in Shanghai, the World Financial Center's ascent is delayed even before it begins. The Asian economy has faltered, and Mr. Mori wants to put off construction until it rebounds.

A. Eugene Kohn: We were to start the super-structure coming out of the ground when he stopped it. Mr. Mori felt he ought to hold up on this until the market got better again.

Narrator: But while construction may have stalled, Mori's vision for the building expands. He dismisses his original design engineers and early in 2001, he hires Leslie Robertson Associates, a prominent New York engineering firm. Robertson established his reputation for innovation when he designed the World Trade Center towers in 1960s.

Leslie E. Robertson: For the World Trade Center, I was the-- what you would call the engineer of record that is, I was responsible for directing the design of the project ... it was a whole new kind of building, compared to that which was done in the past.

Narrator: Built of light-weight steel, not masonry, the towers were the first skyscrapers to have open floors between the services core and the perimeter frame. Instead of pillars holding up the floors, hundreds of thin exterior columns created a tube that was strong enough to support the weight of the building. Floors connected the core to the perimeter, and a giant roof truss helped stiffen the towers against wind. Thirty five years later, Les Robertson will engineer a completely different structure for Shanghai. Mori wants to take the existing plans for his mega-tower...and go bigger. Robertson, however, says height is not what attracted him to the project.

Leslie E. Robertson: I just like to design things and the tallness is not all that important to me.

Narrator: He may shy away from an open declaration of competition -- but the design has just enough floors to keep the Financial Center on pace with its rival in Taipei.

Leslie E. Robertson: The 101st floor is here so you're a rather long ways up in the air. This is 492 meters above the ground. There's the central core -- it's the white part on the inside. It's constructed of reinforced concrete. There are outrigger trusses at three levels that link the core to the structure on the outside ... and then a mega-structure which is the bracing and the large columns on the façade. The three work together to resist wind and earthquake loads on the building.

Saw-Teen See: The Shanghai World Financial Center is the most beautiful sexiest building. I mean the building shape is fantastic because it's different from every angle.

Narrator: With the basic plans in place, the integrity of the design now has to be tested.

Leslie E. Robertson: The building codes in Shanghai kind of restricts the amount you are allowed to have the building lean.

Narrator: So before Robertson can finalize engineering drawings, the new building is sent to a wind tunnel, where Shanghai conditions can be simulated. This plexiglass model is wired with six hundred tiny sensors that will relay information about the structure's behavior under varying wind conditions.

Saw-Teen See: In the wind tunnel, the roughness of the up-wind terrain is simulated by little blocks of buildings that come out from the floor of the wind tunnel.

Narrator: Present and future buildings will affect wind patterns, so the World Financial Center takes its place amongst other buildings in Shanghai's Pudong district. It's closest neighbors are the Jin Mao, currently the world's third tallest, and a black box representing Building Z, a tower yet to be built, but whose height is known, so its influence can be included. The model rotates to expose all sides to the fan. The replica is one five hundredth the size of the actual building, so scaled-down winds represent real currents of hundreds of miles per hour.

Isumov: I'd like to speak to Dr. Les Robertson. We've sent some results today,

Saw-Teen See: The results were fantastic. The forces were in line with what we had predicted -- about half of the acceptable limits so people will be very comfortable.

Narrator: The tests prove that Robertson's lofty design can withstand the elements expected in Shanghai.

Saw-Teen See: In real time, the building would move-- and back. In 6 1/2 seconds. That's very good. I mean, it's-- shows that the building is very stiff.

Narrator: Like all superstructures, Shanghai will move in the wind -- but its stiffness will ensure that it never becomes unstable. At another wind tunnel, Taipei 101 doesn't fair as well. Initial test results show too much vibration in the model -- 30 to 40 percent more than recommended. The results send the architects scrambling back to the drawing board. They design more complicated corners, to lessen the impact of the wind.

C. Y. Lee: When you go to the wind tunnel test, this a sharp angle gonna be making a disaster for the wind so we chop off the corners. From the 90 degree here to a zigzag corner here ... .Like a W, yeah.

Narrator: But the building will need more than "W" shaped corners to decrease the effects of the wind. The supertower has to be flexible to withstand earthquakes -- but that very flexibility makes it prone to excess movement in the wind. The engineers alight upon a solution -- a damping device that will act as a pendulum, to counterbalance the movement of building.

Brian Breukelman: The wind will move the building quite a bit, so the occupants will be able to sense it and the purpose of the damper is to reduce how often they will sense the building moving.

Narrator: Such counterweights are common in tall buildings ... but Taipei 101's will be the heaviest of its kind in the world. 660 tons of steel will be slung from massive cables on the 92nd floor.

Dennis C.K. Poon: It will react by gravity. When the building tends to swing in one direction, the, uh, the two mass damper tries to counter, uh, swing in the opposite direction in order to slow down the acceleration.

Narrator: With the damper solution now in place, plans for the building get finalized. But although engineers know that the building's movement is within safety limits, there is still a question about how much movement is comfortable for the occupants of tall buildings. In a joint project with the Hong Kong University of Science and Technology, Dr. Roy Denoon is simulating building movement -- an experiment to measure the disruptive effects of skyscraper motion.

Roy Denoon: We need to design for that motion, and make sure we minimize it, and bring it down to acceptable levels.

Narrator: This is the world's first motion simulator that can accurately mimic the complex movements of real skyscrapers. It is built to slide in two directions at ninety-degree angles -- what is called two degrees of freedom. The experiment tries to simulate a realistic environment. Volunteers are required to "work" on exercises that involve brain functions like reasoning, logic and concentration. Results will be correlated with different amounts of motion to determine how the building's sway interferes with performance.

Roy Denoon: We're working with very, very sketchy data. We don't know enough about the very tall buildings -- they move much more slowly than the short buildings and the speed with which they move has a major effect on how people perceive the motion. In very tall buildings, the theory is that you perceive it less but we don't have the evidence to know how far we can push the design at the moment.

Narrator: Denoon is trying to prove that people in very tall buildings are not as disturbed by motion as once believed. The results could have a major impact on future building design. Expensive additions like the damper in Taipei 101 may prove to be unnecessary.

Roy Denoon: I think it means we're designing the buildings very well in terms of our current knowledge but perhaps there's a chance that perhaps we're designing them too well, we could be designing them more cheaply.

Narrator: Denoon's research could affect the next generation of tall buildings, but as 2000 passes into the new year, work on Taipei 101's damper begins. Eventually, it will take its place atop the slowly-ascending structure. Rising up from its foundation, are the steel columns that will strengthen the building against seismic activity and wind. The main supports are massive steel-plate box columns welded together in segments. There are eight of them, two on each face, and they measure more than seven square meters at each base. The world's largest crane had to be specially-built to handle their length and weight. On site, they will be strengthened with concrete up to the 60th floor. From there to the top, steel alone will be sufficient to support the weight of the structure. The eight mega-columns run from the massive base of the tower and connect to sixteen smaller columns at the core. Together they bear the vertical load of the building. Every eight floors, at the bottom of each trapezoidal pod, outriggers tie the center to the perimeter. Wrapped around the entire building is a massive steel cage called a moment frame, designed to flex and bend, to absorb seismic energy during an earthquake.

Dennis C.K. Poon: A moment frame is like a grid. It consists of horizontal beams and vertical columns. So, when you, a frame can be very flexible if the connection between the beam and the column is soft.

Narrator: The soft connection is made using steel cut into a dog bone shape -- a reduced beam section that can rotate slightly to prevent buckling of the beams during earthquakes. The summer of 2001 holds a sense of optimism in Taipei. The rapidly growing structure appears perfectly suited to weather all the hazards of the natural world. But then, on a clear blue September morning halfway around the globe, an entirely new threat to skyscrapers is unleashed upon the world ...

... and on this day, our ambition to ascend to the sky seems a misguided pursuit. The only things tangible are the smoke, the rubble, the chaos and the dead.

Saw-Teen See: I was on the phone with Les, in my office, when the first tower came down. It must have been-- difficult for him, not knowing what was happening. You know, the first Tower and then the second Tower. And not knowing who was hurt, and what happened to other buildings around.

Leslie E. Robertson: I just knew that a lot of people had died. I had no idea how many. But, actually, in my mind it was, it was ten, twenty, forty, fifty thousand people, I had no idea.

Saw-Teen See: When we were looking at the burning building, we were thinking that somehow the fire fighters could stop the fire. And that we'll be fixing the building afterwards. It didn't cross my mind that the building would collapse.

Leslie E. Robertson: When I saw the television they had already collapsed. I saw only reruns. And I've asked myself that question, knowing what I know now, about the aircraft, their speed and weight ... I would certainly have no idea whether they would fall or not.

Saw-Teen See: The attack on the World Trade Center is not something that an engineer can design for. One has to look forward to designing other buildings. One has to go on, and designing buildings for people.

Narrator: But no one would go on immediately. The events of 9-11 brought into stark relief the risks of building tall. Skyscrapers under construction around the globe suddenly came under great scrutiny. In Hong Kong, Two International Finance Center -- known as 2IFC -- was half way up. It was on its way to becoming Hong Kong's tallest tower, and the world's third tallest building.

David F. Dumigan: There was a little bit of panic. Were we doing the right thing, building a super high rise? Should-- should we-- should we shorten the building? We were about halfway up. So changes could be made, if changes were necessary.

Narrator: Dumigan and his team went back over their design plans with an eye towards the new threat that 9-11 had introduced. 2IFC -- like the Petronas Towers, and the skyscrapers in Shanghai and Taipei -- has a mega-frame structure with a central concrete core connected to huge steel and concrete columns via outriggers. Before the decision gets made to continue building, those features come under simulated attack at Arup Engineering's London headquarters.

Craig Gibbons: ARUP carried out computer simulations of jet engines, the heaviest part of an aircraft. Crashing into the building.

Narrator: Fire engineer Peter Bressington and his extreme events task force apply software originally designed for analyzing car crashes, to examine what happens to structural steel columns when slammed into by the engine of an airplane.

Peter Bressington: So this is a very standard aviation engine. Along the same line's, is actually, the one that impacted the WTC. And we can see the shaft, the piece of metal and machinery that does the damage.

Colleague: Is there a concrete comparison?

Peter Bressington: Yes there's a concrete mega column shows the same thing happening, the same speed but in this particular case the concrete is protecting the steel inside.

Narrator: This computer simulation is reassuring to the Hong Kong engineers -- whose building has steel columns and a core protected with reinforced concrete. They believe that 2IFC would have fared better in the type of attack that felled the Twin Towers.

David F. Dumigan: If a plane actually hit the building, as in a 9/11 type situation, the building would still remain standing because of the structural system.

Narrator: With concerns alleviated, the decision is made to continue construction on 2IFC. But in Taiwan, similar questions are being asked about Taipei 101.

Harace Lin: We started to receive concerned phone calls from shareholders and the public, raising questions about how are we going to handle it if a similar incident happens in Taipei.

C. P. Wang: So we had an emergency meeting with the owner we tried to simulate what if the similar incident would happen to this building? We know the WTC in NY is basically a tube in a tube design with very thin exterior wall. It is a very smart and genius design to me but in Taipei with the earthquake and typhoon we are not able to do that. We need a very strong building and we have very big steel columns.

Narrator: All of the design work that Taipei 101's engineers and architects had already done to protect the building from earthquakes and wind, now has an unexpected benefit. The mega-structure is so robust the designers feel it could also provide some measure of defense against a 9-11-style attack.

C. P. Wang: If a similar thing happens in our building, we think we would have a little more time for the people to escape to safety.

Narrator: Construction on Taipei 101 continues as planned. And the decision to keep building tall -- and strong in the East is soon reaffirmed by new insight into why the World Trade Center Towers collapsed. Early investigations after September 11th had concluded that the collapse was due to a structural weakness -- that the floor trusses failed, causing the towers to pancake to the ground. But in 2002, the engineering firm Weidlinger Associates came to a different conclusion. Using computer models and sophisticated defense department software, they were attempting to analyze whether the collapse of the south tower contributed to the fall of the other. Engineer Najib Abboud co-authored the analysis.

Najib Abboud: The collapse was initiated through column failures rather than through floor system failures unlike what certain press accounts had surmised in the early days after September 11th. The airplane impacting WTC1, the north tower, was approaching it at about 500 mph. The impact of the airplane remained pretty much central, the airplane continued towards the center of the core. On the south tower, the impact of the airplane was eccentric. It sheared the columns in the corner of the core.

Narrator: Columns throughout both towers were knocked out or broken. Debris from the plane ripped off much of the fire protection on the steel.

Najib Abboud: There is no fire proofing in the world that was ever designed to counter the effects of fragments flying at 500 mile an hour.

Narrator: But still -- the towers stood. The load of the building was transferred via the remaining columns, up to the roof truss.

Najib Abboud: Had the roof truss not existed at all, we believe the collapses would have occurred substantially earlier. That balancing act could have gone on forever had towers did not had to deal with the subsequent fires.

Narrator: These fires, fed by the fuel from the planes, created temperatures as high as seven hundred degrees centigrade.

Najib Abboud: When steel reaches a temperature of around five hundred degrees centigrade at that stage it would have lost half of its load carrying capacity.

Narrator: The columns and the roof truss eventually failed. But the floor trusses -- and the building design -- were not the reason for the collapse. Smoke analysis indicates the floors must have remained intact. On the left, the mass of smoke typically observed when floors are missing. On the right, the differentiated pattern of smoke exhaust and air intake actually observed, floor by floor, at the windows of both towers. The south tower collapsed first, fifty six minutes after it was hit, because it was more unbalanced by the off-center impact of the plane.

Najib Abboud: The north tower outlasted the other one by about twice as much in time. We did prove conclusively that the floors did not contribute and were not the initiating cause, if you will, of the collapses.

Narrator: For designers in Asia -- whose buildings are constructed more robustly to contend with earthquakes and typhoons -- the results confirm that no structural changes are necessary to their ever-growing skyscrapers.

David F. Dumigan: We can't go about trying to design buildings for every type of catastrophe. You know, where do we stop? Do we start designing buildings for nuclear attack?

Narrator: The answer in the building community was a resounding no -- but many planners did begin to pay extra attention to evacuation plans. Due to natural hazards, buildings in Asia need both stronger designs -- and rapid escape strategies. Hong Kong 's 2IFC has both.

Peter Bressington: It's a full scale simultaneous evacuation of a building, we're assuming that all the staircases are available and they're using all their staircases.

Narrator: Peter Bressington's group can predict with confidence that their new building can be evacuated in twenty minutes. That involves 15,000 people descending at the same time from 88 floors. The long descent is protected by a smoke and fire-proof concrete core, and includes places to take refuge on the way down.

Peter Bressington: Refuge floors are a method by which people can move down a building, and go into a space to rest, and if need be, rescued by the firefighters.

Craig Gibbons: One thing that is quite significant about the means of escape criteria in Hong Kong is that there is quite generous stair provision, compared to other codes, the stairs typically are wider.

Narrator: In addition, the stairwells are positioned so that if one fails, it won't cut off the only means of escape. At each refuge level, the design of the building allows people to leave one set of stairs and cross over to another.

David F. Dumigan: It means that if the stair case above gets knocked out for some reason or other the staircases below it are still fully operational. We tell our potential tenants that this is one of the safest buildings in the world today.

Narrator: At other skyscrapers, like the current world's tallest -- the Petronas Towers, it is discovered that evacuation plans may not be as effective as originally thought. Prior to nine eleven, the Towers would practice phased evacuations, simulating a fire at a single location and evacuating a few affected floors. But a bomb threat the day after September 11th made it clear just how inadequate their rehearsals were for dealing with a full-scale emergency. All fifteen thousand occupants had to evacuate the towers at the same time. Fire drills for such a crisis had never been organized.

Major Zanudian Abu Bakar: Basically, we were not prepared for the evacuation of both buildings simultaneously. In fact we were caught with out pants down.

Arlida Ariff: Evidently we did not consider a terrorist attack, or a bomb threat, etc, showing how naïve and innocent we were.

Narrator: Occupants had been trained to use the sky bridge in case of a fire, under the assumption that one tower would remain unaffected. But in this full evacuation, fifteen thousand people were trying to cross the sky bridge at the same time -- all going in opposite directions. The result was mayhem. The evacuation went far slower than anyone expected.

Arlida Ariff: It was completely unforeseeable you would not necessarily have to ever have to worry about having both towers go on fire at the same time.

Major Zanudian Abu Baker: But then, we took it as a blessing in disguise. We came up with procedures to overcome this problem.

Narrator: Following the bomb scare, Petronas security factored elevators into a revised scenario for total evacuation.

SOT: Ladies and gentlemen, may we have your attention please. We just had a confirmation that the building alarm is a real alarm. Eric has the instructions about where you have to go to.

Narrator: Occupants are now instructed to use the elevators -- not just the stairs. Kuala Lumpur fire-fighters can access fires in record time too, via specially reinforced fire, or "bomba" lifts that have back-up power supplies. This is common practice under Asian building codes. Evacuation procedures in Hong Kong's 2IFC also include elevators.

David F. Dumigan: We have two firemen's lifts which take the firemen directly and very quickly to the floor the fire is on. They can also be used to evacuate people who can't actually use the staircase, and these are high-speed lifts, 8 meters per second, that's two floors every second so they can get from the ground floor to the top of the building in less than a minute.

Narrator: The effectiveness of the new evacuation plans at Petronas are clearly visible in this emergency drill. The occupants of the buildings are evacuated eleven floors at a time -- using both the service and express elevators.

Peter Bressington: Elevators are extremely reliable if you are looking at the present generation ones. And it's very rare that they break down and if you are looking at elevators from a fire point of view they need to have from fire protection and some smoke resistance, as well. And that's really quite important.

Narrator: The results are excellent. Using the elevators, the building can be evacuated in just twenty minutes. Building codes in Asia allow for the use of elevators in case of fires, but in the US, evacuation procedures do not. However, the new buildings arising from the ashes of 9-11 will have other safety features that exceed the city's building code requirements. World Trade 7 is the first new building under construction at Ground Zero -- and its designers are committed to making the 57-story building as safe as possible.

David Childs: World Trade 7, being the first building to go back up again, it had to be the, the pace-setter for what would happen on the World Trade Center.

Narrator: One design improvement: Stairs that are twenty percent wider than mandated. This insures that two lines of evacuees won't collide with ascending firefighters.

David Childs: Red lines, now show the people coming down. And also, the firemen going up.

Silverstein: In effect, we have four exits at the base of the building instead of two.

Childs: Right.

Narrator: Like the latest buildings in Asia, World Trade 7 will also have a two-foot thick reinforced concrete core

David Childs: New York, for a host of practical and union and financial reasons, built steel buildings with steel cores. In Chicago and Los Angeles and London and Kuala Lumpur we usually build, buildings with concrete cores. So this is not a new technology, but it's new for New York.

Narrator: The steel buildings of New York are certainly strong enough to withstand the region's natural forces -- but 9-11 has brought new concerns. The concrete core will help fireproof the building, and give occupants more time to escape in emergencies.

David Childs: So you fireproof it to a degree that lets people get out of the building. The building falls down in twelve hours that's one problem but you have enough time to get the people out.

Larry A. Silverstein: In the last analysis we're going to have at seven the safest high rise building that's been built in the United States and whatever it is we do here at seven, we're going to incorporate at the Twin Towers site.

Narrator: The "safest high rise" in the United States, however, will still fall far short of Asian safety standards. World Trade 7's goal is to evacuate 8,000 people from fifty seven floors in under an hour. Modest compared to the 15,000 in twenty minutes at Petronas and Hong Kong, but still an improvement over other US buildings. As development plans go forward in New York, the construction race in Asia continues to play out. But on March 31st, 2002, the engineers at Taipei 101 get a jarring reminder of why they must make their building so strong. In Taiwan, earthquakes are a serious concern -- the country straddles a Pacific fault line that sends tremors rumbling through the region several times a year. Now, with the building about two thirds completed and vulnerable, its strength is prematurely put to the test.

Brian Bruekelman: The way the earthquakes hit in Taipei here is you first get some vertical motion, so you sense that structure going up and down and you say, " OK, this is not normal," and then I knew exactly is was an earthquake ... and I quickly ran under one of the column lines in case something from above were to come crashing down.

Narrator: People run for cover as a 6.8 level earthquake rocks the city. Hundreds of feet above the ground, the two huge construction cranes begin to lean ... Five people are killed when the cranes plummet to earth. But Taipei 101 remains standing, and structurally intact.

Dennis C.K. Poon: I was kind of worried about Taiwan how other buildings would behave but no time I worried about the building because we fully know that this building is designed above -this magnitude of earthquake.

Narrator: The building may have survived -- but the cranes caused damage as they fell. Construction has to be stopped for seven months while repairs are made. In Shanghai, the World Financial Center is also affected by earthquakes, but in a less dramatic and damaging way. Chinese building authorities have requested further assurance that their tall building conforms to their new earthquake design standards. In early 2003, Les Robertson and his team in New York make the necessary adjustments to their latest structural model.

Leslie E. Robertson: One of the problems is that the building code is not organized to think about buildings so tall. It's-- it's thinking about buildings that are perhaps a third as high. It's been a difficult task. We have one more meeting with the earthquake experts, And then-- government acceptance of the design will have been completed.

Narrator: February 13th, 2003. Minoru Mori hosts a second ground-breaking ceremony in Shanghai. This unusual event is a signal to the world that the race is back on. It is announced that the tower will be completed by 2007. But in the meantime, Taipei 101's climb to the roof of the world remains uncontested. All eyes are trained on Taiwan ... where history is about to be made.

June 30th, 2003: Morning calisthenics for the engineers at Taipei 101 -- a routine beginning to another day of construction. But today, the pressure is on. In a few hours, the damper, as heavy as 550 automobiles, will be permanently suspended at the top of the building. A month earlier, all its elements were partially assembled on site, and the main supporting cradle was hoisted to the eighty seventh floor. One by one, 40 steel plates, weighing as much as 27,000 kilograms each, were layered to form a massive sphere measuring almost six meters across at its equator. The damper will occupy the center of five entire floors, from the 87th to the 92nd. At the moment, it rests on powerful hydraulic jacks.

Brian Breukelman: Those supports, those will be pulled out and then the jacks will be released slowly and the whole mass will come down and hang on the cables. The process to this lifting and then lowering will probably take an hour to two hours.

C.P. Wang: The damper to us is like the heart of the building it's a very important element part of the building. We want people to see it and to also feel comfortable with it. So we put restaurants and observation decks around that area so people can see this gold ball hanging in the space, so that the gold is shining in that area.

Narrator: Before the day is out, the damper is in position and the steel rigging has reached the hundred and first floor. Taipei 101 is now only four meters shorter than Petronas Towers, the world's tallest building.

July 1st, 2003 -- Topping Out Day. In a tradition observed the world over, the final steel beam is hoisted into place. The event is commemorated with a party and a day off.

C.Y. Lee: It's the biggest day because when the building says this is the final stage, nothing you can change ... .so that's probably the important moment for me.

Narrator: But in fact, something will change on the building -- and an even more important day will arrive just a few months later. On October 17th, 2003, Taipei 101's sixty-meter pinnacle is jacked into place above the hundred and first floor. Once again, history is made. The structure is now 508 meters high -- It beats out Petronas by over 50 meters!

C.Y. Lee: In this 101, we have so many problems, you know. I think it's a miracle already we can get done. In this time, in this place!

Construction Workers: TAIPEI 101!!!

Narrator: This is now the world's tallest skyscraper. ... at least -- for the moment. After false starts and delays, the Shanghai World Financial Center is back on track ... and owner Minoru Mori is still thinking big:

Minoru Mori: I am building the tallest building in the world.

Narrator: Not only that, but plans have also been floated to add the world's highest Ferris wheel to the moongate at the top of the building. It is likely to be much like the London Eye on the banks of the Thames -- but a whole lot higher. People would be riding on gondolas over 400 meters above the ground.

William Pedersen: The Ferris wheel was introduced when we, realized that the dynamics of moving, around this circle, within that space could be an extraordinary thing. Mr. Mori is a very theatrical developer. He primarily wants people to enjoy his buildings.

Leslie E. Robertson: Would I ride in it? Well of course I would ride in it. Actually I'd have no choice because if I wouldn't ride in it, no one else would.

Narrator: Nothing is certain -- but if all goes according to Mori's dream, the Shanghai supertower will take the title of world's tallest in 2007.

Leslie E. Robertson: No building-- currently constructed in Shanghai is to anywhere near the standards that we're using for the Shanghai World Financial Center. So, it will be head and shoulders-- actually much more than that, above other buildings.

Narrator: But soon after Shanghai's completion, the West may once again challenge for the title. The new tower at the World Trade Center site will be five hundred and forty meters, or 1776 feet ... a symbolic height that could eclipse both Taipei and Shanghai.

Larry A. Silverstein: The Freedom Tower will be the tallest building in the world upon its completion, 1776 feet in height, eclipsing by some number Minoru Mori's building in Shanghai, and when he heard that our building was going to be higher still than his, I felt for him because I could see that, a sense of, a sense of dismay. And we're going to have the freedom tower in place, end of '08, beginning of '09, it'll happen.

Narrator: It is too early to tell what final decisions will be made in New York. But whatever the result, the Freedom Tower is not the only grand plan waiting in the wings. A developer in Dubai recently announced plans for an eight hundred meter skyscraper. Called Burj Dubai -- it could smash all previous records by a healthy margin if it becomes a reality. For now though, it exists only as a model ... that fits nicely into this little box.

Bill Baker: In this box I have a model of what's going to be the world's tallest building. It's the Burj Dubai project, and it's a residential tower in Dubai. And we've lost our spire. Here it is. Okay. And there you have it, put the spire on. Burj Dubai. At this point the height is confidential. But, we are very comfortably taller than any other buildings out there. The Shanghai building, which is proposed to be the world's tallest building, doesn't quite measure up to this building. Its height is somewhere is this range here.

Narrator: For builders in New York, Shanghai, and Dubai, the ambition to build taller has not died. And as technology advances and building designs become ever more innovative, humankind is always looking to a point higher in the sky. Picturing, planning, and dreaming of the day when we can touch the heavens with towering monuments of concrete and steel.


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A Carlton Productions LLC production for Thirteen/WNET New York In association with Carlton International.

© 2004 Educational Broadcasting Corporation and Carlton International

INNOVATION was produced by Thirteen/WNET New York, which is solely responsible for its content.

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