Clay Rotunda
© Gramazio Kohler Research

Clay Rotunda

Gramazio & Kohler as Architects

The Clay Rotunda is a free-standing earth-based cylindrical structure constituting the outer, soundproof shell of the SE MusicLab, a high-fidelity music auditorium built inside the newly refurbished Gurten Brewery in Bern. The cylindrical structure combines clay, a sustainable zero-waste building material, with computational design techniques. Featuring a diameter of almost 11 meters the structure reaches a height of 5 meters with just 15 cm of unreinforced clay. It was built in-situ by a mobile robotic system that aggregated over 30’000 soft clay bricks over a period of 50 days.

photo_credit © Gramazio Kohler Research
© Gramazio Kohler Research

The extreme slenderness of the Clay Rotunda is made possible by its undulated design, which allows to increase the footprint and stabilize the structure in order to prevent buckling effects.The computational model that controls the geometry of this thin shell was designed by taking into account the structural models of the engineers, the material properties of the clay as well as the sequencing of the building process.

photo_credit © Gramazio Kohler Research
© Gramazio Kohler Research

The optimisation of the material system is key for the performance of the structure. For the Clay Rotunda different compositions of clay, sand, small stones and water have been tested with the aim of finding the best balance between the malleability needed by the fabrication process, the highest compressive strength, and the minimal material shrinkage. The developed clay mix is extruded into so-called soft bricks, cylinders with a diameter of 9 cm and a height of 15 cm, which are grabbed by the robotic arm from a picking station, precisely oriented, and sequentially pressed into their final position. The compression of about 60% of the original height assures a strong and interlocking aggregation, leading to a soft bond that expresses both the plasticity of the material and the dynamic forces of the fabrication process.

photo_credit © Gramazio Kohler Research
© Gramazio Kohler Research

The custom robot - the in-situ fabricator - had to be moved for every single segment in order to address the full scale of the structure. This relocation of the robot as well as the deformation of the fresh material caused by its shrinkage required a regular acquisition of the as-built geometry through 3D scanning. The unavoidable cracks that resulted from the drying process were actively monitored and regularly filled with the same clay mix.

photo_credit © Gramazio Kohler Research
© Gramazio Kohler Research

The Clay Rotunda addresses the urgent need of reducing the material consumption as well as revert to emission-free materials for the fabrication of our built environment. The robotic clay aggregation process combines the traditional knowledge of clay constructions with contemporary digital design and fabrication processes. The increased degree of control on both material and process allows building complex structures that go beyond what has traditionally been possible. Clay also has excellent properties in regulating the interior climate of buildings, thus reducing the need for mechanical ventilation and creating comfort for all inhabitants. Finally, earthen constructions are entirely waste-free, since the used clay mix can be ground and fully reused. What is taken from nature can be returned entirely to nature.

photo_credit © Gramazio Kohler Research
© Gramazio Kohler Research
Project Spotlight
Product Spotlight
News
C.F. Møller Architects demonstrates importance of evidence-based architecture to providing therapeutic mental health services
28 May 2024 News
C.F. Møller Architects demonstrates importance of evidence-based architecture to providing therapeutic mental health services

Danish architectural firm C.F. Møller Architects has completed the Springfield University Hos... More

Conen Sigl transforms the site of a former Swiss plant nursery into a cooperative housing complex
28 May 2024 News
Conen Sigl transforms the site of a former Swiss plant nursery into a cooperative housing complex

Switzerland-based architecture studio Conen Sigl has transformed a former plant nursery plot near Zu... More

Studio Libeskind completes striking affordable senior housing courtyard building in Brooklyn
27 May 2024 News
Studio Libeskind completes striking affordable senior housing courtyard building in Brooklyn

The renowned international architectural practice Studio Libeskind has completed the Atrium at Sumne... More

25 best interior door manufacturers
27 May 2024 Specification
25 best interior door manufacturers

Beyond their obvious role of creating privacy and acting as transitions between different areas with... More

Sanjay Puri, Dominique Petit-Frere, Emre Arolat and Yenny Zhang join Archello Awards 2024 jury
23 May 2024 Archello Awards
Sanjay Puri, Dominique Petit-Frere, Emre Arolat and Yenny Zhang join Archello Awards 2024 jury

Sanjay Puri, Dominique Petit-Frere, Emre Arolat and Yenny Zhang have been announced as Archello Awar... More

Storefront in Amsterdam by Dok architecten features sculpted facade of hand-molded bricks
23 May 2024 News
Storefront in Amsterdam by Dok architecten features sculpted facade of hand-molded bricks

The Italian fashion brand Dolce & Gabbana has opened a store in Amsterdam's P.C. Hooftstraat ret... More

Prokš Přikryl Architekti converts historic grain silo into multifunctional conference and art space
22 May 2024 News
Prokš Přikryl Architekti converts historic grain silo into multifunctional conference and art space

Prague-based Prokš Přikryl Architekti has converted the grain silo of a historic mill buildin... More

Surman Weston veils self-build Peckham House in hit-and-miss brickwork
21 May 2024 News
Surman Weston veils self-build Peckham House in hit-and-miss brickwork

London-based architectural studio Surman Weston has completed its first self-build project in the vi... More