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Old Posted Apr 7, 2022, 11:51 PM
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‘Supertall’ Review: Kissing the Clouds

By Anthony Paletta
April 6, 2022 6:10 pm ET

. . . Mr. Al, a Dutch architect based in New York, writes that “we are living in an urban age where the most tangible architectural expression . . . is the supertall.” In 1996, he notes, the Council on Tall Buildings and Urban Habitat only classed four buildings as “supertall”: 984 feet or taller. “Today, there are more than one hundred seventy, with about a dozen completed every year—each taller than the Empire State Building.”

. . . Mr. Al’s account spans the behemoths of Asia and the Middle East, the pencil-thin towers of Manhattan, the eccentric geometries of high-rise London, the vertical gardens of Singapore, and more.

The sheer volume of calculation required to build and keep these structures aloft and functioning is astounding. Mr. Al, who has written an excellent book on the architecture of the Las Vegas Strip, explains these esoteric technical challenges in lucid fashion. If steel was the literal foundation for the first century of skyscrapers, reinforced concrete is that of the second. The latest “ultra-high-performance” concrete, Mr. Al explains, supports “about 26,000 pounds of pressure per square inch—the weight of three African elephants on an area the size of a postage stamp.”

As Mr. Al informs us, the precise ingredients of concrete, and the ways in which you combine them, are vitally important. Local sand was too round and small for the Burj Khalifa in Dubai, so Australian sand was shipped in. One key innovation in recent decades is the use of “superplasticizers,” synthetic polymers that render concrete stronger and workable for longer.

Supertalls don’t merely have to support their own weight; they have to resist wind pressure. The darkest prospect is vortex shedding, in which a strong wind causes air to separate from the building’s surface, “creating two symmetrical and adjacent low-pressure eddies on the downwind side,” as Mr. Al writes. As wind speed increases, the vortexes begin to alternate from side to side, which could lead to disaster if the movement coincides with the building’s natural vibration. “In this case,” Mr. Al writes, “even small amounts of wind can lead to major oscillations, and could lead to collapse.” He likens the phenomenon to an opera singer shattering a wine glass.

Wind pressure has spurred developers to devise irregular shapes, relieving the monotony of the rectangle. The Canton Tower in Guangzhou, China, for example, is something of a cylinder cinched in the middle, while the Turning Torso in Malmö, Sweden, twists upward. Tuned mass dampers, large devices that move in the reverse of the tower’s motion, are standard in these sorts of buildings.

Getting to the top is a challenge; walking 3,000 stairs is not an option. Contemporary supertalls rely on innovations like high-speed “express” elevators and double-decker cars. The Empire State Building’s elevator initially traveled 14 miles per hour; current elevator speed is up to 47. Elevators today are safer than ever: The Shanghai Tower features safety gears that “can withstand friction heat as high as 1,000 degrees Celsius” and a telescopic buffer at the base of the shaft that serves as a life net.

Another problem (and massive environmental hazard) is the tremendous amount of climate control required in supertalls, where operable windows are generally unthinkable. The Burj Khalifa, for instance, has seven double-level mechanical floors to move water and supply air-conditioning. Desert supertalls may seem the diametric foe of energy efficiency, but Mr. Al surveys some recent experiments to find ways of mitigating this waste.

According to Mr. Al, New York is the city of the “super slenders,” which are largely residential, as opposed to the commercial skyscrapers of the previous century. Some of these “Billionaires’ Row” sylphs are ugly, but he puts in a welcome good word for the concept. “Super slenders balance the skyline,” he writes. “Aesthetically speaking, their thin peaks add big crescendos, allowing for diminuendos elsewhere, avoiding the otherwise monotonous solid wall of equally high-pitched buildings.”

Hong Kong features a far denser skyline but has done a better job of integrating the buildings into the city, with plentiful direct connections to transit and frequent links between buildings above the first floor. In Singapore there have been welcome efforts to achieve more sustainable buildings and to bedeck them with greenery. The architect Moshe Safdie topped his Marina Bay Sands with a “SkyPark.” The city’s Tree House, at 24 stories, may not be supertall, but one of its sides is covered by a vertical garden.

Mr. Al’s account isn’t simple boosterism, but it does dodge the tone of miserablism that characterizes so much attention to our skylines. Supertalls are fascinating and immensely complicated undertakings that demand admiration—and lots of work. Even if tweaks are necessary, the story of what’s come about in the age of the supertall is gripping. “If we can harness our ingenuity to build structures up in the clouds,” Mr. Al wisely counsels, “then we can also create structures that are good for the planet down on earth.”
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https://www.wsj.com/articles/superta...ts_pos3&page=1
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Old Posted Apr 12, 2022, 10:24 PM
muertecaza muertecaza is offline
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Thanks for posting. I read the NYT review today and added it to my "to read" list.

https://www.nytimes.com/2022/04/12/b...supertall.html

Quote:
...It is no accident that the skyscraper came into being in the United States as this country was becoming a major presence on the world stage. Putting up tall towers was a way of flexing American muscle, of showing the world that this country was capable not only of amazing engineering feats but of building entire cities around them. The brilliant engineer Gustave Eiffel could create his tower as a symbol, but he did not reshape modern Paris. It would be on the relatively cleaner slates of New York and Chicago that the 20th century would assert itself in the making of a new kind of skyline. And the skyscraper would become one of the most significant contributions America would make to international culture.

Much of the world was quick to embrace jazz, another U.S. export of roughly the same vintage. Skyscrapers would take a good bit longer to catch on. They would remain mostly an American phenomenon until toward the end of the 20th century. And that is about where Stefan Al takes up the story in “Supertall: How the World’s Tallest Buildings Are Reshaping Our Cities and Our Lives,” which is a thoughtful inquiry into the current generation of skyscrapers, buildings that are generally taller than their predecessors, more numerous and more widely spread around the world. Many of them are even more daring as works of engineering than their forerunners: staggeringly thin, thanks to advances in structural design, and reaching great heights. Some of this new wave of skyscrapers inspire awe, but more of them surely inspire resentment. There is, after all, less and less novelty to the notion of a tower that rises to more than 1,000 feet; they seem now to be everywhere, and they have changed the scale of major cities around the world.

That is the premise behind this book: This is not your grandfather’s skyscraper that you are seeing out your window; the new generation of skyscrapers is bigger and more ubiquitous than the one that came before. What has happened to the skyline in recent years has made the expectation that 9/11 would lead to the skyscraper’s demise seem like a quaint memory. We may not like all of what this age of supertall buildings has given us, and Al is not insisting that we should. Al, a Dutch architect based in New York who did a stint on the staff of Kohn Pedersen Fox, a prolific international designer of tall buildings, writes clearly. He understands that skyscrapers are a product of technology, finance, zoning, marketing, social preferences and aesthetics, and that to ignore any one of these categories is to misunderstand the subject.

Al divides his book into two main sections, Technology and Society: the first a set of chapters about things like concrete, wind and elevators; the second a series of essays about cities — London, New York, Hong Kong and Singapore — each of which he presents as a case study of different political, social and economic attitudes toward the skyscraper. There is a lot of rich history here, well and concisely told (and illustrated with superb line drawings, a refreshing change from the big, splashy photographs of coffee-table books).

London is the example of an old and mostly low urban fabric now being infiltrated by skyscrapers, with questionable results; Hong Kong is seen as a vast machine, where towers cluster tightly together and an efficient mass transit system makes it all work as almost an integrated unit. Singapore, a place in which landscape has been woven not only into the urban design, but also into the structures of the new towers themselves, may be Al’s ideal: a dense, high-rise garden city. New York is, well, New York, where the new supertall and superthin residential towers stand as a troubling symbol. “As ingenious as these structures may be, they are also markers of increased inequity and societal risk,” Al writes. He calls them “a high-end world, a capitalist who’s who of the most expensive and luxurious real estate available.”

Still, Al is a mostly enthusiastic booster of the supertalls, sometimes to the point of excess or cliché, like when he calls them “the cathedrals of our time,” or writes that “truth is stranger than fiction: That’s the story of architecture today.” But then the social challenges that supertall buildings present bring him back down to earth, as it were, and he recovers his clear and critical eye. He believes that in an age of explosive urban growth we will need to continue to build tall, but he argues that building tall by itself is not enough: We need to find ways to do it that are greener, healthier and more sustainable without sacrificing beauty. He doesn’t pretend to know exactly how, but he knows that we will have to make the skyscraper something more than just, as the architect Cass Gilbert called it long ago, “the machine that makes the land pay.”
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