Wood-Veneer-Reinforced Mycelium Composites for Sustainable Building Components

Abstract

The demand for building materials has been constantly increasing, which leads to excessive energy consumption for their provision. The looming environmental consequences have triggered the search for sustainable alternatives. Mycelium, as a rapidly renewable, low-carbon natural material that can withstand compressive forces and has inherent acoustic and fire-resistance properties, could be a potential solution to this problem. However, due to its low tensile, flexural and shear strength, mycelium is not currently widely used commercially in the construction industry. Therefore, this research focuses on improving the structural performance of mycelium composites for interior use through custom robotic additive manufacturing processes that integrate continuous wood fibers into the mycelial matrix as reinforcement. This creates a novel, 100% bio-based, wood-veneer-reinforced mycelium composite. As base materials, Ganoderma lucidum and hemp hurds for mycelium growth and maple veneer for reinforcement were pre-selected for this study. Compression, pull-out, and three-point bending tests comparing the unreinforced samples to the veneer-reinforced samples were performed, revealing improvements on the bending resistance of the reinforced samples. Additionally, the tensile strength of the reinforcement joints was examined and proved to be stronger than the material itself. The paper presents preliminary experiment results showing the effect of veneer reinforcements on increasing bending resistance, discusses the potential benefits of combining wood veneer and mycelium’s distinct material properties, and highlights methods for the design and production of architectural components.

HOME: Wood-Mycelium Composites for CO2-Neutral, Circular Interior Construction and Fittings

“…where Fp is the pull-out force, t and w are the veneer thickness and width respectively, and l is the embedded veneer length in the mycelium matrix [28]. The embedded length was fixed to 75% of the cube height.…”

“…All tests resulted in a pull-out failure rather than a tensile failure, which indicates that the IFSS of veneers in the mycelium matrix is much lower than the tensile strength of the veneer itself. Further research is currently being carried out to determine factors affecting the IFSS and to improve the bonding mechanism between the veneer and the mycelium matrix [28].…”

“…Furthermore, it was observed that the use of veneer reinforcement improved the failure mechanism where no sudden rupture of the panels was observed. Further research on investigating the impact of veneer species, their layouts and locations on the load bearing capacity, rigidity, ductility, and stability of the newly developed wood-mycelium composite panels are currently under way, and initial results have been recently published in [28].…”

Mycostructures—growth-driven fabrication processes for architectural elements from mycelium composites

“…The reinforcing potential of this weaved surface is assumed due to over growing of the surface with mycelial skin and merging of two entities [19]. Also the fundamental research work of Özdemir [22] bears the inclination to this form giving methodology by investigating the influence of maple veneer stripes in forms of 2d and 3d lattices as the reinforcement of MCBs.…”

Sustainable Mycelium-Bound Biocomposites: Design Strategies, Materials Properties, and Emerging Applications

“…Although mycelium-bound biocomposites suffer from a lack of specification standards and challenges of comparisons of resultant properties due to the different biofabrication approaches, it is worth noting that the protocol for mycomaterial production is not complex. It utilizes low-cost materials, demands less energy (biological growth), and produces highly circular and sustainable materials. − Because of the many parameters and variables in the production of mycelium-bound biocomposites, it is worth noting that the full potential of the mycelium-bound biocomposites has not been unlocked . However, there has been incredible progress in this field because of the increased environmental awareness and the sustained push for governments, industry, and academia to provide solutions toward achieving net zero carbon emissions by 2050 …”