Gramazio Kohler Research
Open Positions
Compas FAB
Compas Timber
AIXD: AI-eXtended Design
AI-Augmented Architectural Design
Impact Printing
Human-Machine Collaboration
AR Timber Assemblies
Architectural Design with Conditional Autoencoders
Integrated 3D Printed Facade
Think Earth SP7
Robotic Plaster Spraying
Additive Manufactured Facade
Timber Assembly with Distributed Architectural Robotics
Eggshell Benches
Autonomous Dry Stone
Data Driven Acoustic Design
Mesh Mould Prefabrication
Data Science Enabled Acoustic Design
Thin Folded Concrete Structures
Adaptive Detailing
Deep Timber
Robotic Fabrication Simulation for Spatial Structures
Jammed Architectural Structures
Digital Ceramics
On-site Robotic Construction
Mesh Mould Metal
Smart Dynamic Casting and Prefabrication
Spatial Timber Assemblies
Robotic Lightweight Structures
Mesh Mould and In situ Fabricator
Complex Timber Structures
Spatial Wire Cutting
Robotic Integral Attachment
Mobile Robotic Tiling
YOUR Software Environment
Aerial Construction
Smart Dynamic Casting
Topology Optimization
Mesh Mould
Acoustic Bricks
Additive processes
Room acoustics
View of the finished pavilion.
Left: Printed formwork. Middle: Prefabricated reinforcement cage. Right: Final concrete column.
Close-up of the column crown at the interface with the wooden structure.

Close-up of the fused deposition modelling 3D printing process.
Future Tree spanning over the courtyard of Basler & Hofmann office building - vizalization

Removal of the thin formwork using a heatgun.
Full-threaded screws connecting the timber elements.

3D Printing the thin formwork with a six-axis robotic arm and vertical linear axis.
Every timber element is cut to size and placed by a robot.

FutureTree, Esslingen, 2017-2019
Demonstrating our research in complex timber structures and digital concrete, the Future Tree is an eye-catching canopy, spanning over the courtyard of the office building extension of Basler & Hofmann in Esslingen, Switzerland.

The crown of the Future Tree is a timber structure made of 380 timber elements forming a reciprocal frame, supported by the concrete column, anchored to the building on two sides and cantilevering on the opposite corner. The frame’s geometry is informed by its structural behaviour, differentiating its flexural rigidity by playing with the opening of the reciprocal knots to achieve a higher stiffness in the cantilevering part. To integrate geometric, structural and fabrication concerns we developed a custom computational model of the design. The structure is made of acetylated pine wood, full threaded screws and tension cables. The timber elements have been fabricated and assembled using an industrial robot.

The Future Tree’s stem is a reinforced concrete column, made using an ultra-thin robotically 3D printed formwork which is combined with a fast-hardening concrete. This novel fabrication process, known as “Eggshell”, allows for the fabrication of non-standard, structurally optimized concrete structures, whilst being able to integrate standard reinforcement and minimize formwork waste. In the Eggshell process a formwork with a thickness of 1.5mm is 3D printed using a robotic arm. The reinforcement is then placed and the formwork is filled with a fast-hardening concrete in a layer-by-layer casting process. This assures that hydrostatic pressure exerted onto the formwork is kept to a minimum. After hydration of the concrete, the thin formwork is removed and can be recycled. As a first built example using this fabrication method, it shows that non-standard concrete structures can be fabricated efficiently, economically and sustainably.

Apolinarska, Aleksandra Anna, Mathias Kuhn, Fabio Gramazio, Matthias Kohler. Performance-Driven Design of a Reciprocal Frame Canopy - Timber structure of the FutureTree. (eCAADe 2021) PDF

Burger, Joris, Ena Lloret-Fritschi, Nizar Taha, Fabio Scotto, Thibault Demoulin, Jaime Mata-Falcón, Fabio Gramazio, Matthias Kohler, Robert J. Flatt. Design and Fabrication of a Non-standard, Structural Concrete Column using Eggshell: Ultra-thin, 3D Printed Formwork. (Second RILEM International Conference on Concrete and Digital Fabrication. Digital Concrete 2020) PDF

Gramazio Kohler Research, ETH Zurich

In cooperation with: Physical Chemistry of Building Materials group (ETH Zurich, Prof. Dr. Robert J. Flatt, Dr. Thibault Demoulin, Bruno Pinto Aranda)
Client: Basler & Hofmann AG
Collaborators: Dr. Aleksandra Anna Apolinarska, Dr. Ena Lloret-Fritschi, Joris Burger, Nizar Taha, Fabio Scotto
Selected experts: Basler & Hofmann AG, ERNE AG Holzbau, SJB Kempter Fitze AG, Concrete Structures & Bridge Design (ETH Zurich, Prof. Walter Kaufmann, Dr. Jaimé Mata-Falcon)
Selected contractors: ERNE AG Holzbau (Fabrication timber structure)

Copyright 2024, Gramazio Kohler Research, ETH Zurich, Switzerland
Gramazio Kohler Research
Chair of Architecture and Digital Fabrication
ETH Zürich HIB E 43
Stefano-Franscini Platz 1 / CH-8093 Zurich

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