Extrusion Asia Edition 3-2016

37 Extrusion Asia Edition 3/2016 （按照DIN 4102）标准，不仅是在美 国，对世界各地来说这都是一个重要的 标准。建筑师和屋顶策划人员对于大雪 负载时巨蛋型屋顶的承载能力给予了特 别的关注，因为原先这一建筑物只有一 半大小，在2010年12月由于受到超过 半米厚的积雪重压而坍塌。ETFC薄膜 的抗撕裂强度特性值抗，以及继发撕裂 和抗穿刺特性都非常好，空气填充的衬 垫很容易应对高度集中的冲击载荷比如 冰雹。这种材料在北欧和阿尔卑斯山区 的使用已经证明：哪怕是在有暴雪的地 区，其性能对冬季是适合的。 非对称的屋顶更多地朝向北方倾斜 以应对积雪。薄膜是非常平滑的，由于 其表面抗粘附，所以积雪根本很难附 着，并会按照几乎是可控制的方式滑 落。一场大雨的冲淋足够将屋顶打扫清 洁。 O utside temperatures of minus 30 de- grees are usual during the American Football season from September to the beginning of February. Therefore, only closed stadiums are the only choice in the north of the USA. In order to create a genuine open-air atmosphere at least in summer, architects have often made use of movable, but expensive roofs in the past. The ETFE film cushion technology, which is already widespread in Europe and Asia, was used for the first time in the US by the HKS Architects for the construction of the new multi-purpose stadium in Minneapolis, thus lowering the construction costs by around USD 100 million as compared to a retractable roof. Round about 75 three-layer ETFE film cushions cover the total roof and facade area of 22,000 square metres. The U.S. Bank Stadium is thus the largest ETFE film project in the US. Some of the indivi- dually air filled cushions are more than 110 m long and around 3 m wide. The top film is printed with a geometric pat- tern, which scatters the sunlight and pre- vents a greenhouse effect in summer. In winter, the film roof protects the interior from the cold outside temperatures. The film cushions manufactured from 3M Dyneon ETFE allow 95 percent of the daylight to pass through, but their weight is only about five percent that of glass. As a result, the supporting steel structure can be particularly light and slender and offers all spectators an opti- mum view of the playing field. The entrance consists of five giant glass doors, which are over 30 m in height and remain open in summer. Vector Foiltec built the film construction that joins onto them. With 14 offices worldwide, Vector Foiltec covers the entire spectrum from the conception to the support structure planning and from the manufacturing of the cushions to their installation. The films are extruded from 3M Dyneon ETFE by Nowofol Kunststoffprodukte GmbH & Co. KG, NOWOFLON ® ET 6235Z films are available in thicknesses from 80 to 400 microns. Nowofol produces the films in a wide range of RAL colours as well as in transparent and, completely new, in an infrared absorbing variant. The films conform to fire protection class B1 (according to DIN 4102), which is an important criterion – not just in the USA. The architects and the roof planners paid particular attention to the load bearing capability under high snow loads, be- cause the roof of the Metrodome, the predecessor building that was only half as large, collapsed in December 2010 under the heavy load of more than half a meter of snow. ETFE films feature very good values for tear strength, resistance to tear propagation and puncture resis- tance which let the air filed cushions ea- sily cope with highly concentrated im- pact loads like hail. Their use in northern Europe and the Alps proves their winter compatibility, even in areas with heavy snowfall. The asymmetric roof is inclined more to- wards the north in order to fend the snow off. Due to their anti-adhesive sur- face, the films are so smooth that snow can hardly get a grip at all and slides off – in an almost controlled manner. A heavy rain shower is enough to clean it. 美国银行体育场有着透明的屋顶结构，采用3M Dyneon氟塑料ETFE高性能挤出薄膜 The US Bank stadium is featuring a transparent roof construction with high- performance films extruded from 3M Dyneon Fluoroplastic ETFE (Copyright Minnesota Vikings) 3M Company www.3M.com