With roof in place and its set of nine facades closing, the bustling work on what will be the latest commercial jewel in Amsterdam’s developing southern business sector is turning inward: just the 650 guest rooms, restaurant, landscape and a television studio left to kit out.
While project manager Adri Last ofPleijsier Bouwsays that should be on schedule for later this year or beginning next, over recent months the builders engaged the most challenging of the project’s engineering works.
When guests finally do enter the new nhow Amsterdam RAI hotel, developed and operated by the NH Hotel Group and designed by Rem Koolhaas’sOffice of Metropolitan Architecture，他们将走进该地区最大的酒店，高90米（近300英尺），超过25层，其中有三个楔形。每个体积围绕中央主轴旋转60°，地板悬臂高达15 m（50英尺）。
“If you build with two rotations, it is going to be more difficult,” Last says. The trickiest part will never be seen: the basement and parking garage are sunk in a small plot underground, pilings at an incline. The piling incline had to match the tunnel wall of an adjoining and newly-built metro subway line, with the outer wall of the basement dug in as close to a meter away from the sleek new tube.
然后how Amsterdam RAIhotel will mark the new edge of a sprawling convention center, Amsterdam RAI, which has a 125-year history going back to late-19th century bicycle trade shows (Rijwiel en Automobiel工业, or bicycle and auto industry, gave the place its name).Benthem Crouwel Architects最近除了复杂的设计,its Elicium addition, opening in 2009 with Arup as structural engineer. It is the sort of exhibition space better navigated by bicycle: the halls are set over a vast square, Europaplein, with 90,000 sq m (22 acres) of meeting space.
邻里和环境正在快速剪辑。这是Zuidas, or south axis, the shiny financial and business district easily spotted on approach to Schiphol airport or on the rail into the city. This area over the last three years added lanes and tunnel to the big ring highway running through it, also opening the north-south metro subway (with a new RAI stop) and expanded its south rail station, following a城市发展计划。The nhow Amsterdam RAI is flush against the metro line and its intersecting commuter line. It will hold hundreds of guests and conventioneers but it also marks the corner of the “green border,” a large triangular park and public space, Beatrixpark, stretching behind the RAI.
The designers and builders had to contend with a small and tightly-constrained building footprint, a seven-sided polygonal plot, and while the cantilevering and volume rotation is aesthetic—there’s a nod there to the RAI’s well-recognized, wedges-on-a-column entrance marketing pylon—OMA and project architect Michel van de Kar says lifting the building as a whole, using a relatively small part of the space for the ground floor, means at that level the hotel only covers 800 sq m out of the entire 4000 sq m of the plot.
That’s 20% of the footprint, and leaves most of the rest for public space and landscaping. This helps connect the space to the adjoining areas, with pedestrian flow a vital aspect. Every morning the metro and commuter rail stations bring large numbers of people up to the street, and bicycles—this is Amsterdam, after all—whiz constantly through. It also, van de Kar says, set up the design and engineering work that followed. Setting the large volumes over a relatively small plinth liberated the ground floor and landscape around it, but also brought in the cantilevering.
It flows from the one central concrete core through the building and is a feature of most of the floors of the building, says project structural engineer Steven Schoenmakers of Van Rossum. The building volumes are triangles, each one with six to eight floors, with the overall structure resembling a kind of dessert display. The edges of each triangle are 60 m long. The designers first considered cantilevering from the core, doubling the distance of the overhang, but that did not work. The solution, Schoenmakers says, was to find central, overlapping lines within the three volumes where builders could position columns. From the concrete core, a floor is cantilevered to a main wall running midway through the volume, and from the big concrete wall, the floor continues out 15 m, the extended portion constructed with lightweight steel decking.
Schoemakers说：“我们必须重新计算每个楼层，因为每层都是悬臂系统的一部分。”每卷的顶部带来了额外的紧张，项目设计人员还需要考虑风。“建筑物的形状意味着地板上有扭转。”工程师绘制计算以根据风洞测试来解决此问题。并非每个楼层都以相同的方式结构。顶部的三角形体积高7层，但在顶部两层，没有墙壁结构可以制造悬臂。中间体积包含六个悬臂地板，底部，八个。该团队在立面上使用垂直钢制胸罩。在每个体积的九点处，有一个结构通过混凝土柱加固的点。
Going up, each volume is rotated 60° from the one beneath it. This also made for some Tetris-style thinking, van de Kar says. “By turning and mirroring across the main axis we could use the same floor plates. It makes sense in developing the structure,” he says. It was a complex operation, he notes, since each floor is different. For van de Kar, the triangles compute: “In the end it’s a very rational building.”
