SimBio-Wall
Symbiotically Living Architectural System for Stronger Circular Built Environment
University of Pennsylvania coursework 2022.9-11
Collaborators: Ji Yoon Bae, Chunze Li, Xinlin Lu, Tinghui Mo

1. INTRODUCTION

Fungi has gained architects’ attention as a sustainable building material. The fungi-based materials are biodegradable at the end of the life cycle. In this regard, mycelium has been implemented in the field of architecture across the scale. Hy-Fi, designed by The Living, is an early example of fungi-based architectural installation that illustrates circular material life cycle (Benjamin, 2014). Another research, Mycotree, done by Block Group at ETH Zurich tackled the structural performance of the mycelium built pavilion by developing the load-bearing spatial branching structure (Heisel et al., 2017). While both precedents opened up the possibility of mycelium as a construction material, the material opportunities were only limited to the biodegradable characteristic and structural investigation.

Mycelium is a living matter. Environmental advantages of this living material are eliminated once it’s baked to stop growing and to be used for construction. In this matter, the research starts with the question about how we might utilize the mycelium as a living construction material that creates a stronger circular built environment. To tackle this hypothesis, the research team looked at the symbiotic behavior of fungi with plants. Mycorrhizae, the symbiotic association between fungi and plants, is a renowned sustainable planting strategy for providing vegetation with nutrients and maintaining good soil health (Bianciotto et al., 1996). These mutualistic dynamics have been deeply studied in plant biology while focusing on their interactions between a fungus and a plant, which exchanges water and mineral nutrients with carbohydrates. While living architecture has become one of the popular approaches for sustainable design, this symbiotic behavior has not been explored in the architectural research. Therefore, this research aims to develop a mycorrhizae informed living architectural system that performs as a fully biodegradable building component. Moreover, these symbiotic architectural components are expected to mutually interact not only within a building component itself but also with the surrounding environment.

2. METHODOLOGY

The research builds upon the previous investigation that explores a growing behavior of mycelium within the 3d-printed unfired clay shell to make a fully biodegradable and recyclable circular life cycle. This preliminary research phase revealed the stable growing process of mycelium onto the unfired clay surface. The current progress mainly focuses on developing the research pipeline of symbiotically living architectural components that interact with the surrounding environment. Fungi and plants exchange benefits with each other. Fungi provide plants with minerals and water while absorbing carbohydrates created by plants’ photosynthesis. This circular nutrient flow allows plants to grow stronger without use of chemical fertilizer. The research intends to implement this biological process into the field of architecture by developing the symbiotically living wall systems coupling with robotic clay deposition. The 3d-printed clay shell provides a system with better structural benefits and geometric freedom compared to the current state of the arts. The system allows mycelium to keep growing onto the clay shell surface and to perform as a bio-adhesive. The plants react to the surrounding environment by absorbing carbon dioxide and releasing oxygen back to the atmosphere.

To elaborate this biology-informed architectural system, the research team plans to investigate the following:
1) The customized substrate recipes, coco coir, vermiculite and gypsum (CVG), are tested to find an optimized condition for mycorrhizal growth;
2) Non standard geometries of clay shell are designed and fabricated by leveraging generative design process and robotic clay deposition. The geometries and its surfaces are mainly informed by the both computational and physical tests, which aims to validate its structural stability from geometry itself and mycelium bonding process;
3) SimBio-Wall, the full scale wall prototype, will be constructed to prove its architectural applicability;
4) The proposed system will be evaluated by the metrics such as structural stability, life cycle assessment, and environmental performances under the certain geographical and climatic constraints.

3. RESULTS

Recently, mycelium has been utilized as a biodegradable construction material. Mycelium-based products disintegrate spontaneously once they have completed their intended product life cycle. Mycelium composites, which are manufactured by growing mycelium on agricultural waste, might produce low-cost and greener building materials, potentially reducing the construction industry's reliance on fossil fuel-based products. In terms of its properties and development potential, the process of Mycelium composites being a kind of greener building material is refining. By taking these potentials of mycelium as a construction material, the research intends to fortify benefits and overcome the limited material opportunity. Most mycorrhizae are mutualistic, which means that the fungus gives the plant soil resources in return for photosynthates. This new understanding is now used in agricultural practices. We focus on arbuscular (AM) and ectomycorrhizae (EM), the most common types. Based on the above-mentioned theoretical support, transitioning back to thinking about applications in the architecture field. Some of the constructed successful cases are mainly centered around mycelium brick. The research team considered figuring out a biodegradable symbiotic living wall and forming a stronger circular built environment.

4. IMPACT

SimBio-Wall is a living architectural system that couples symbiotically living bio-materials with digital fabrication technologies. Built upon the current utilization of mycelium as a biodegradable building material, the mycorrhizal based living wall system further allows mycelium and vegetation to environmentally perform as a part of the built environment. By creating a closed loop of symbiotic ecosystem within the architectural component, the system responds to the outdoor environment in the appropriate climatic context.

References

Heisel, Felix, Karsten Schlesier, Juney Lee, Matthias Rippmann, Nazanin Saeidi, Alireza Javadian, Dirk Hebel, Philippe Block. 2017. “Design of a load-bearing mycelium structure through informed structural engineering: The MycoTree at the 2017 Seoul Biennale of Architecture and Urbanism.”, in Proceedings of the World Congress on Sustainable Technologies (WCST).
Bianchitto, Valeria, Claudio Bandi, Daniela Minerdi, Massimo Sironi, Hans Volker Tichy, Paola Bonfante. 1996. “An Obligately Endosymbiotic Mycorrhizal Fungus Itself Harbors Obligately Intracellular Bacteria.”, Applied and Environmental Microbiology: 3005-3010.
Egerton-Warburton, L M, J I Querejeta, M F Allen, S L Finkelman. 2005. “Mycorrhizal Fungi”, Encyclopedia of Soils in the Environment: 533-542
The Living. 2014. “Hy-Fi”, an installation project at MoMA P.S.1.