2023年5月19日至11月26日，gmp展览《UMBAU·改建，不间断转变》在威尼斯举办。此次展览以建筑改建为主题，这是gmp对全球气候变化的回应，也是就此话题寻求公共对话的表现。自1977年第一个改建项目开始至今，gmp已完成或正在进行的建筑改建项目共有64个。在这个系列中，我们将详细介绍有代表性的五个。

From May 19 to November 26, 2023, the gmp exhibition titled "UMBAU. Nonstop Transformation" will take place in Venice. The exhibition focuses on architectural transformations and serves as gmp’s response to global climate change while seeking public dialogue on this theme. Since the first transformation project began in 1977, gmp has completed or is currently working on 64 such projects. In this series, we provide a detailed introduction to five representative projects among them.

两项翻新措施让乌尔里希·穆特在马格德堡的双曲面壳体屋顶建筑遗址免遭拆除，并再次焕发出未来的活力。最新的碳纤维混凝土技术恢复并提升了这个充满想象力的屋顶壳体的荷载能力。巨大的室内空间被划分为更灵活的小空间，同时保留了令人印象深刻的大跨度屋顶所带来的壮观效果。

It took two interventions to save the ruins of Ulrich Müther’s Hyparschale in Magdeburg from demolition and restore it to a future-ready state. The load-bearing capacity of the visionary roof shell is being reestablished and even improved thanks to state-of-the-art carbon concrete technology. The large interior is being subdivided into smaller rooms for more flexible programming, without diminishing the imposing impression made by the broad roof above.

马格德堡的双曲面壳体屋顶建筑鸟瞰 © Marcus Bredt

1969年–2017年

马格德堡双曲面壳体屋顶建筑是民 主德国最富创造力的建筑工程师乌尔里希·穆特（Ulrich Müther，1934年-2007年）保存至今的规模最大的作品。他的标志性设计是双曲屋面，即双曲抛物面，通过曲面自行承重，以极少的建筑材料跨越宽阔的无柱空间。穆特将其称为“Hyparschale”。

The Hyparschale in Magdeburg is the largest remaining hall roof by a man who was arguably East Germany’s most inventive structural engineer, Ulrich Müther (1934 – 2007). His trademark was the double-curved roof surfaces, or “hyperbolic paraboloids” supported by their own curvature, which allowed the roof to span extremely wide spaces without columns and using very little material — for which Müther coined the term “hyparschale.”

双曲抛物面壳体 © Marcus Bredt

穆特在马格德堡双曲面壳体屋顶建筑中挑战了当时的技术极限。他不仅想用一个双曲抛物面壳体覆盖48米见方的屋顶面积，还要将屋顶分成大小相同的四块，每块屋顶都是正方形平面的双曲抛物面。屋顶单元之间的空隙由玻璃砖补充，在大厅中心汇成一个星形的天窗。

For his Magdeburg Hyparschale, Müther pushed the technological possibilities of his day to their limits. He not only wanted to span a 48-square-meter area with a double-curved roof slab without supports, but he also wanted to subdivide the roof surface into four equal subparts, each suspended over a square floor plan and each of which was double-curved into itself. Between these roofs, he installed fenestration bands that came together at the center of the hall to form a star-shaped skylight.

星形天窗 © Marcus Bredt

就当时的建筑技术来说，屋顶上星形天窗的构想过于大胆。尽管屋顶承重不是问题，但玻璃砖带来了大厅内的渗水问题。开放不久后，天窗用沥青纸材料全部封闭。穆特在设计中追求的那种通透、轻盈及纤薄的大厅屋顶效果消失殆尽。

The idea of a star-shaped skylight was considered too daring for the structural possibilities of the time. Although the roof held up, water seeped between the bands of glass components and dripped into the hall. Shortly after it was opened, the skylights were completely sealed with tar paper, putting an end to Müther’s intended effect of a transparent, lightweight, and elegant hall roof.

被分成四块的屋面 © Marcus Bredt

随着时间的推移，薄壳混凝土屋顶出现了多处裂痕，加固钢筋也开始生锈。1997年，由于严重的坍塌隐患，建筑被封起并计划拆除。但市民和国际专家们的抗议让人们意识到了这一独特结构的建筑文化价值，并最终拯救了这座壳体结构。在未能找到私人投资者的情况下，马格德堡市于2017年决定自行对建筑进行修复工作。

Over the years, the thin concrete roof also broke off in a number of places and the reinforcing steel rusted. Faced with an imminent threat of collapse, the Hyparschale was closed in 1997 and slated for demolition. Protests were held by citizens and international experts who cited the architectural value of this unique structure and ultimately succeeded in saving the shell. After failing to find a private investor, the City of Magdeburg itself decided to refurbish the Hyparschale in 2017.

翻新中的壳体建筑 © Marcus Bredt

2017年–2024年

我们与Prof. Rühle, Jentzsch und Partner事务所的工程师、德累斯顿Carbocon公司的碳纤维混凝土专家以及德累斯顿工业大学重型结构研究所合作，提出了用碳纤维混凝土来修复屋顶的新型改造修缮方案。

Together with the engineering firm of Rühle, Jentzsch und Partner, carbon concrete specialists Carbocon Dresden, and the Institute of Concrete Structures at Technical University Dresden, a proposal was developed for using a new refurbishment process to save the Hyparschale that involved repairing the roof with carbon concrete.

屋面翻新 © Marcus Bredt

首先将现有屋顶内、外表面都打磨粗糙，以便覆上一层薄的特制混凝土层，然后再涂上一层薄薄的细质混凝土层。这一层铺设了由碳纤材料编制成的网格，然后再用特制混凝土覆盖。这样，壳体内、外各加建了最厚为10毫米的具有抗腐蚀性的加固层。这种方法在不改变屋顶规模的情况下，甚至增加了结构的承重能力。天窗也终于重见天日。

The existing roof is roughened inside and out so that a thin layer of special concrete can be applied. This is followed by a thin layer of shotcrete. Carbon fiber textiles are placed on this layer and sealed with special concrete. The result is a maximum 10-mm-thick, corrosion-resistant layer on both sides of the roof slabs that also serves to increase the structure’s load-bearing capacity without changing the dimensions of the extremely thin skin of the roof. The fenestration bands can finally be uncovered.

天窗重建天日 © Marcus Bredt

在建筑内部，大型空间按照城市的要求被灵活分割成较小的单元。我们采用了穆特正方形平面的基本体系，在大厅的角落布置了四个正方平面的空间单元。这些空间单元可以通过滑动、旋转和折叠元素互相组合，也可以与它们之间的通道区域组合在一起。

The city wanted a flexible division of the large interior space into smaller units. We replicated Müther’s basic square-based system and developed four square rooms positioned in each of the four corners of the hall. Using sliding, rotating, and folding elements, these rooms can be combined with one another and with the circulation areas between them.

四个正方形的空间单元 © gmp architects

中间区域在顶部保持开放，就像上面的天窗一样，在大厅中部聚成宽敞的中央空间。从这里到大厅天花板一览无遗。此外，四个空间单元的屋顶是可通行的，并通过通道连接在一起，形成一个夹层回廊。站在回廊上，乌尔里希·穆特的大弧度屋顶的宏伟姿态依然可见，人们甚至可以无限接近屋顶。

The intermediate zones remain open to the roof and, like the fenestration bands, come together in the center of the hall to form a large, central room with an unobstructed view of the hall ceiling. The roofs of the four room boxes can also be traversed and are interconnected via bridges. This creates a gallery level from which the massive gesture of Ulrich Müther’s curved roof not only remains visible, but visitors can now get a closer look than ever before.

夹层回廊 © gmp architects

最终，我们借助最新的建筑技术方法，能够忠于穆特在1969年完成的设计进行建造，使其延续下去，并对城市产生实际价值，同时使建筑比以前更加明亮通透。我们的改建并不是原建筑的复原，而是优化，是根据创作者乌尔里希·穆特的理念进行的升级。

Ultimately, use of the latest architectural processes was what makes it possible to take Müther’s design from 1969 and construct it in a way that is true to the original and durable, allows the city to put it to good use, and makes the building more transparent. Our conversion isn’t just a reconstruction of the original hall. It’s an improved version — an update consistent with its inventor, Ulrich Müther.

翻新后的建筑将更加明亮通透 © Marcus Bredt