不过这么多摩天大楼，欣赏壮观城景之余，我们不免想问，要是刮个超级台风什么的，这些以500米高楼为首的一群“标准模特”就不怕么？ 别怕，设计师们早已经为这些大楼安装了千吨级风阻尼，即使在台风肆虐的情况下依旧能保持楼房的稳定，甚至就连楼房的晃动都能被控制在较小范围内。 1956 年，建筑师弗兰克·劳埃德·赖特 (Frank Lloyd Wright) 提出了一座一英里高的摩天大楼，这座建筑是埃菲尔铁塔的五倍。虽然这座巨大的塔从未建造过，但今天，越来越大的建筑物正在世界各地拔地而起。这些不可能的想法是如何变成建筑机会的？Stefan Al 解释了这些巨型建筑如何成为我们城市天际线的固定装置。 演讲者：Stefan Al演讲题目: Will there ever be a mile-high skyscraper?
In 1956, architect Frank Lloyd Wright proposed a mile-high skyscraper. It was going to be the world’s tallest building, by a lot — five times as high as the Eiffel Tower. But many critics laughed at the architect, arguing that people would have to wait hours for an elevator, or worse, that the tower would collapse under its own weight. Most engineers agreed, and despite the publicity around the proposal, the titanic tower was never built.1956年，建筑师弗兰克 · 劳埃德 · 怀特提议建造一座1英里高的摩天大楼。它将比世界上其他任何建筑高都要出许多——它会是埃菲尔铁塔高度的五倍。但是许多评论家嘲笑这位建筑师，因为人们将会花好几个小时等电梯。更甚，这座大厦将会因无法承受自重而倒塌。大多数工程师赞同这一说法，尽管这个提议广为人知，但这项工程从未启动。But today, bigger and bigger buildings are going up around the world. Firms are even planning skyscrapers more than a kilometer tall, like the Jeddah Tower in Saudi Arabia, three times the size of the Eiffel Tower. Very soon, Wright’s mile-high miracle may be a reality.但如今，世界各地的建筑越建越高。很多公司甚至在计划建造超过1千米高的摩天大楼，比如，沙特阿拉伯的吉达大厦是埃菲尔铁塔的3倍高。在不久的将来，怀特那1英里高的建筑设想也许就成真了。So what exactly was stopping us from building these megastructures 70 years ago, and how do we build something a mile high today?所以70年前到底是什么绊住了人们建造这些巨型建筑的脚步，而我们如今又是如何建成一英里高的建筑的呢？In any construction project, each story of the structure needs to be able to support the stories on top of it. The higher we build, the higher the gravitational pressure from the upper stories on the lower ones. This principle has long dictated the shape of our buildings, leading ancient architects to favor pyramids with wide foundations that support lighter upper levels. But this solution doesn’t quite translate to a city skyline– a pyramid that tall would be roughly one-and-a-half miles wide, tough to squeeze into a city center.在每项建筑工程中，每一层建筑都需支撑它上层的部分。建筑越高，底层结构所承受的来自上层的压力就越大。这个原理一直以来限制了建筑的形状，因此古时候的建筑师们偏爱地基宽阔的金字塔结构，它可以承受住 更轻的上层部分。但是这个方案并不能很好地适应城市布局——一个近1.5英里宽的金字塔底座很难在城市中心安身。Fortunately, strong materials like concrete can avoid this impractical shape. And modern concrete blends are reinforced with steel-fibers for strength and water-reducing polymers to prevent cracking. The concrete in the world’s tallest tower, Dubai’s Burj Khalifa, can withstand about 8,000 tons of pressure per square meter– the weight of over 1,200 African elephants!幸运的是，诸如混凝土这样坚实的材料可以避免这种不切实际的形状。在新型混凝土中混入钢纤维能加大强度，减水剂能避免建筑出现裂痕。世界上最高的塔，迪拜的哈利法塔的混凝土可以承受每平米约8000吨的压力——这相当于1200头非洲象的重量！Of course, even if a building supports itself, it still needs support from the ground. Without a foundation, buildings this heavy would sink, fall, or lean over. To prevent the roughly half a million ton tower from sinking, 192 concrete and steel supports called piles were buried over 50 meters deep. The friction between the piles and the ground keeps this sizable structure standing.当然，即便一座建筑可以自我支撑，它还需要地基的支持。没有地基，如此重的建筑就会下陷、坍塌或者倾倒。为了防止这个约有五十万吨重的塔下陷，192个被称为桩的混凝土和钢筋支架被埋进50米深的地下。地与桩之间的摩擦力可以使这座庞大的建筑屹立不倒。Besides defeating gravity, which pushes the building down, a skyscraper also needs to overcome the blowing wind, which pushes from the side. On average days, wind can exert up to 17 pounds of force per square meter on a high-rise building– as heavy as a gust of bowling balls. Designing structures to be aerodynamic, like China’s sleek Shanghai Tower, can reduce that force by up to a quarter. And wind-bearing frames inside or outside the building can absorb the remaining wind force, such as in Seoul’s Lotte Tower.除了可以将整栋楼推倒的重力的威胁，一栋摩天大楼也需要客服从大楼侧面吹来的风力。一般情况下，风能在高层建筑上施加17磅（约 7.7 千克）每平方米的力——相当于一堆保龄球的重力。设计的建筑结构要符合空气动力学，例如中国的地标建筑，上海中心大厦，可以减少四分之一的风力。而建筑内或外的承风框架可以同化剩余的风力，例如首尔的乐天大厦。But even after all these measures, you could still find yourself swaying back and forth more than a meter on top floors during a hurricane. To prevent the wind from rocking tower tops, many skyscrapers employ a counterweight weighing hundreds of tons called a “tuned mass damper.” The Taipei 101, for instance, has suspended a giant metal orb above the 87th floor.但即使采取了这些措施，在飓风来袭时，你仍然会发现自己在顶楼左一米、右一米的摇晃。为了防止风摇动塔顶，许多摩天大楼采用了一种重达数百吨的“调谐质量阻尼器”。例如台北101大楼在87层以上悬挂着一个巨大的金属球体。When wind moves the building, this orb sways into action, absorbing the building’s kinetic energy. As its movements trail the tower’s, hydraulic cylinders between the ball and the building convert that kinetic energy into heat, and stabilize the swaying structure.当风吹过大楼时，这个球体开始摇摆，吸收大楼的动能。当它拖着上层楼摇摆时，球和建筑物之间的液压缸会将吸收的动能转化为热能，以此稳定摇摆的结构。With all these technologies in place, our mega-structures can stay standing and stable. But quickly traveling through buildings this large is a challenge in itself. In Wright’s age, the fastest elevators moved a mere 22 kilometers per hour. Thankfully, today’s elevators are much faster, traveling over 70 km per hour with future cabins potentially using frictionless magnetic rails for even higher speeds. And traffic management algorithms group riders by destination to get passengers and empty cabins where they need to be.当所有这些技术被加以应用时，我们的巨型建筑才能够稳定站立。但是快速穿过如此庞大的建筑物本身就是一项挑战。在怀特的那个年代里，最快的电梯仅以每小时22公里的速度运行。值得庆幸的是，如今的电梯速度快得多，时速可超过70公里，未来的轿厢可能会使用无摩擦的磁轨以实现更快的速度。交通管理算法根据目的地将乘客分组，以确保乘客和空轿厢被送到他们需要去的地方。Skyscrapers have come a long way since Wright proposed his mile-high tower. What were once considered impossible ideas have become architectural opportunities. Today it may just be a matter of time until one building goes the extra mile.自从怀特的“一英里摩天大楼”被提出以来，摩天大楼经历了许多变迁。曾经被认为是不可能的想法已成为建筑界的契机。让一栋楼多增高一英里，现在看来，很可能只是时间问题。 Remark：一切权益归TED所有，更多TED相关信息可至官网www.ted.com查询！
