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The Smart Takes from the Strong: 3D Printing Stay-in-Place Formwork for Concrete Slab Construction

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Abstract

The wider aim of this research is to explore the architectural potential of additive manufacturing (AM) for prefabricating large-scale building components. It investigates the use of AM for producing building components with highly detailed and complex geometry, reducing material use and facilitating the integration of technical infrastructure. In order to achieve this, the concept of stay-in-place 3D printed formwork is introduced. AM is employed to produce sandstone formworks for casting concrete in any shape, regardless of geometric complexity. This approach explores the synergy between the geometric flexibility of 3D printing sand formworks and the structural capacity of concrete. It allows the production of composite components with properties superior to either individual material. This new fabrication method is demonstrated and evaluated with two large-scale 1:1 ceiling slab prototypes, which are described in this paper.
Aghaei-Meibodi, Mania, Mathias Bernhard, Andrei Jipa,
and Benjamin Dillenburger. 2017.
The Smart Takes from the Strong
In Fabricate, edited by Bob Sheil, Achim Menges, Ruairi
Glynn, and Skavara Marilena, 210–17. London: UCL
Press. https://doi.org/https://doi.org/10.14324/111.
9781787350014.
https://www.jstor.org/stable/j.ctt1n7qkg7.33
ACHIM MENGES / BOB SHEIL / R UAIRI GLYNN / MARILE NA SKAVARA
... The Smart Takes from the Strong project (Figure 6a) showcased binder jetting for stay-in-place, non-structural formwork [40]. Two 1.8 m 2 slab prototypes with a network of topology optimised ribs were produced with ultra-highperformance fibre-reinforced concrete cast in a 9 mm thick binder jetted shell. ...
... Ribbed slabs with binder jet 3D-printed formwork: (a) stay-in-place formwork for the Smart Takes from the Strong[40]; (b) reusable formwork for Fast Complexity[41]; and (c-f) disposable formwork for the DFAB HOUSE Smart Slab[31], illustrating (c) the spraying of the concrete cover, (d) the casting of the ribs, (e) the installation on-site, and (f) the soffit of the finished slab. ...
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... The advantage of AM in general, but especially in the building industry, is the faster and cheaper production by a higher degree of automation, thus enhancing economic aspects. In addition, the sustainability can be increased through new methods, such as the manufacturing with supplementary cementitious materials, for example calcined clay instead of pure Portland cement clinker, or optimized structures, which focus on material savings while maintaining the same load-bearing capacity [2]. ...
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... Compared to comparable structures, the resulting slab uses up to 70% less material. Another study explores the use of stay-in-place formwork for producing a TO slab [13]; [14]. Two different prototypes are designed in different programs and fabricated using the same technique. ...
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Chapter
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