Zusammenfassung

The utilisation of bio-based materials has significantly increased in recent years, driven by a growing awareness of environmentally friendly alternatives in the construction industry. This study introduces innovative natural fibre pultruded profiles for load-bearing applications in structural systems. By employing pultrusion technology with flax fibres and customised plant-based matrix, linear and unidirectional biocomposite profiles were developed. These profiles were used in the creation of LightPRO Shell, an active-bending structure combining biocomposite profiles with a membrane outer skin, demonstrating their mechanical properties and suitability for such applications. The paper focuses on the geometrical and structural design development of the structure employing computational design tools for optimisation, ensuring design parameters and performance requirements were met. The final structure, a 10-m span doubly curved gridshell, features a continuous perimeter beam and consists of 44 profiles ranging from 6 to 12.5 m, showcasing the potential of natural fibre biocomposites as sustainable alternatives in construction.

Zusammenfassung

Reevaluating the materials that shape our built environment holds significant importance for sustainable construction. This research introduces newly developed natural fibre pultruded profiles, composed of flax fibres and bio-resin, customised for specific properties and targeted applications. Engineered to withstand both bending and compression loads, these profiles have been subjected to rigorous mechanical testing to demonstrate their compression and flexural strength, as well as flexibility. The emphasis lies on the bottom-up design approach, guiding the creation of applications suitable for this innovative material in various lightweight structures. The paper presents a series of case studies showcasing the use of biocomposite profiles in diverse design and structural contexts. The initial focus was on active-bending structures, highlighting the material’s flexibility, showcased at a ten-metre span structure, the first large-scale demonstrator. However, given the material’s versatile properties, it is suitable for a wide range of other applications. Key case studies discussed include reciprocal, tensegrity and deployable structures, as well as modular planar or space frame systems. These profiles offer a sustainable and versatile alternative to traditional materials and composites, providing innovative and eco-friendly construction solutions while contributing to industry sustainability goals.

Zusammenfassung

Material selection is crucial for advancing sustainability in the building sector. While composites have become popular, biocomposites play a pivotal role in raising awareness of materials deriving from biomass resources. This study presents a new linear biocomposite profile, fabricated using pultrusion technology, a continuous process for producing endless fiber-reinforced composites with consistent cross-sections. The developed profiles are made from flax fibers and a plant-based resin. This paper focuses on the application of these profiles in tensegrity systems, which combine compression and tension elements to achieve equilibrium. In this study, the biocomposite profiles were used as compression elements, leveraging their properties. The methods include geometrical development using physical and digital models to optimize the geometry based on material properties and dimensions. A parametric algorithm including physics simulations was developed for this purpose. Further investigations explore material options for tension members and connections, as well as assembly processes. The results include several prototypes on different scales. Initially, the basic tensegrity principle was built and explored. The lessons learned were applied in a final prototype of 1.5 m on a furniture scale, specifically a chair, integrating a hanging membrane serving as a seat. This structure validates the developed system, proving the feasibility of employing biocomposite profiles in tensegrity configurations. Furthermore, considerations for scaling up the systems to an architectural level are discussed, highlighting the potential to enhance sustainability through the use of renewable and eco-friendly building materials, while promoting tensegrity design applications.

Zusammenfassung

The use of bio-based materials has been increasing in recent years owing to a growing awareness of ecologically friendly alternatives in the building industry. This work demonstrates the application of natural fiber biocomposite profiles within a reciprocal structural framework. Employing the pultrusion technique, linear profiles are fabricated using natural flax fibers and a bio-based resin. This paper focuses on the design and implementation of a parametric model that generates reciprocal systems considering the geometric and mechanical properties of this newly developed material. Reciprocal systems were chosen due to their high density of shorter linear elements, capacity for global geometric diversity, simplicity of joint assemblies, and low structural dependence on the joints. The developed algorithm considers material properties and site requirements to transform a line network into a stable reciprocal system with given cross-sections and generates pre-fabrication and assembly instructions to reduce on�site complexity. The proposed method was initially validated with a small demonstrator, confirming its accuracy from design to fabrication. A larger canopy showcased at the Venice Biennial demonstrated the system's scalability and the applicability of biocomposite profiles for complex applications.

Zusammenfassung

Reconsidering the materials used in construction is crucial within the building industry, particularly in the context of sustainability. Recently, there has been a growing interest in exploring novel materials, with fibre-reinforced composites emerging as a prominent choice with biocomposites standing out as promising for advancing sustainability goals. This paper introduces the development of LeichtPRO-Profiles, continuous linear biocomposite profiles fabricated using the pultrusion technology. A primary focus is the application of these profiles in structural systems as load-bearing elements, emphasising the significance of understanding their mechanical properties. Specifically, an original application involves active-bending structures, necessitating a focus on the material’s bending behaviour. This study discusses the methods employed in developing the pultruded biocomposite profiles which are made from natural flax fibres and an optimised matrix formulation based on a plant-based resin system. This research also outlines the optimisation of the fabrication process of these biocomposite profiles using bio-based ingredients. The results demonstrate the material’s mechanical capabilities through extensive experiments and mechanical tests, revealing a compression strength of 31.2 kN and a flexural strength of 300 MPa, with a bending radius of up to 2.4 m, indicating its suitability for structural applications. Concepts of applications in several systems across different scales and contexts are also presented. The versatility and adaptability of this product make it suitable for a wide range of applications spanning various scales and thematic contexts.

Zusammenfassung

The selection of materials in the construction industry plays a pivotal role in advancing sustainability goals. Traditional materials derived from natural resources face inherent constraints linked to geographic limitation, growth time, and geometric inconsistency and therefore recent attention has shifted towards developing novel bio-based materials. Composites, offering varying properties and geometries, are becoming increasingly popular for customising materials for specific applications. Pultrusion, a technology for manufacturing linear fibre-reinforced composites, is a well-established and reliable method. This study delves into optimising pultrusion technology, which traditionally relies on synthetic fibres, by exploring the potential of natural alternatives, specifically hemp bast fibres. Additionally, it presents a customised formulation based on a plant-based resin and additives. This formulation is tailored for pultrusion to produce high-performance biocomposites for use as load-bearing components in structural applications, with an initial focus on bending structures. The study elaborates on the material composition and performance of these newly developed natural fibre pultruded profiles, showcasing their mechanical capabilities through rigorous experimentation and testing. The results demonstrate the material's mechanical capabilities showcasing a flexural strength of 260 MPa with a bending modulus of 21 GPa and a bending radius reaching 0.5 m. While this study focuses on the material formulation tested on laboratory-scale pultrusion, the findings will be later applied in an upscaled production at an industrial level, aiming to enhance overall sustainability in the construction industry.

Zusammenfassung

In a resource-constrained world, raising awareness about the development of eco-friendly alternative materials is critical for ensuring a more sustainable future. Mycelium-based composites (MBC) and their diverse applications are gaining popularity as regenerative, biodegradable, and lightweight alternatives. This research aims to broaden the design potentials of MBC in order to construct advanced systems towards a novel material culture in architecture. The proposed design method intends to explore the design and fabrication of small-scale components of MBC to be applied in modular systems. Mycelium-based modular components are being developed to fulfill the geometrical requirements that allow for the creation of a lightweight system without additional reinforcement. The modules are linked together using an interlocking system. Through computational design and form-finding methods, various arrangements of the modules are achieved. An initial prototype of five modules is created to demonstrate the ability of the system to form various geometrical configurations as a result of the used workflow. The proposed application aims to expand the scope of the use of mycelium-based composites in modular systems and to promote architectural applications using bio-based composite materials.

Zusammenfassung

There is an essential need for a change in the way we build our physical environment. To prevent our ecosystems from collapsing, raising awareness of already available bio-based materials is vital. Mycelium, a living fungal organism, has the potential to replace conventional materials, having the ability to act as a binding agent of various natural fibers, such as hemp, flax, or other agricultural waste products. This study aims to showcase mycelium’s load-bearing capacities when reinforced with bio-based materials and specifically natural fibers, in an alternative merging design approach. Counteracting the usual fabrication techniques, the proposed design method aims to guide mycelium’s growth on a natural rattan framework that serves as a supportive structure for the mycelium substrate and its fiber reinforcement. The rattan skeleton is integrated into the finished composite product, where both components merge, forming a fully biodegradable unit. Using digital form-finding tools, the geometry of a compressive structure is computed. The occurring multi-layer biobased component can support a load beyond 20 times its own weight. An initial physical prototype in furniture scale is realized. Further applications in architectural scale are studied and proposed.