Regenerative Approach in Sustainable Composite Structure Design for Building

Abstract

By integrating living organisms and their intelligent capabilities at the heart of the design process, design evolves towards a creation in harmony with the surrounding nature. Therefore, the designer is led to reconsider the way they design sustainable solutions, capable not only of integrating but also of acting as living entities within their ecosystem. This approach promotes continuous interaction with the environment, fostering mutual enrichment where design and nature mutually enhance each other. Designers have the ability to reintegrate nature into the creation of materials and collaborate with natural resources. This reintegration fosters mutual positive impacts between natural and human systems. Such interactions lead designers to envision proactive scenarios for future habitats, merging scientific knowledge to co-evolve with nature. The design thus becomes a catalyst for transforming the design paradigm towards interconnectedness harmonious with the environment. In this context, it involves co-creation with living organisms from a perspective of bio-integrity rather than anthropocentrism, contributing to the regeneration of natural systems, restoration of human health, and preservation of biodiversity. While this approach presents a forward-thinking perspective, our empirical study seeks to demonstrate its potential implications in our daily lives and the real world. We have attempted to explore various methods and tests to incorporate the microorganism Ulva algae into the process of developing a living construction material, with the aim of promoting a locally regenerative approach.

1 Introduction

Currently, design is more than ever at the heart of the biological era where life emerges as a productive alternative. By integrating living organisms and their intelligent capabilities into the core of the design process, design has sought to surpass nature and envision “new life”, exploring novel symbioses between living beings and their environment, and consequently between the design object and its surrounding milieu. This is presented in the form of a “Living design” approach. This approach aims to transform the design paradigm towards a harmonious interconnection with the environment. Such interactions lead designers to consider proactive scenarios for future habitats, merging scientific knowledge to co-evolve with nature. This raises the question: how can design act as a catalytic agent to promote the sustainability and regeneration of healthy natural ecosystems?

Based on a research-creation approach, we have endeavored to present our empirical study that combines scientific knowledge with design perspectives to work with living organisms for a regenerative and sustainable approach. We were particularly interested in the specificity of the “ulva” algae, abundant in our locality, and its significant impact on the health of local biodiversity due to overproduction. Through various tests and experiments, we sought to explore the possibilities of incorporating these algae into the design of a “living” biomaterial to promote a regenerative approach. Our experimental study focuses on how to work with and mimic living organisms, aiming to regenerate natural systems rather than exploit and destroy them.

2 Living Design Contribute to Creating a More Sustainable Future

2.1 Synergy of Design and Synthetic Biology: Create «Alive»

Designers have embraced advancements in biology and technology, exploring innovative approaches to living organisms and their processes. By integrating the living and its vital intelligences into design, we have pushed beyond the traditional boundaries of design, not only drawing inspiration from nature but also working directly with the living itself to shape our future and “cultivate” life The biological revolution has given rise to a new generation of biologist-designers who are attempting to adopt a new line of research that guides their work in scientific reflection, enriching their ability to think within the full complexity of biology, whose principal actor is the living organism. Thierry Marcou, in his article “Towards a Design of Synthetic Life”, introduces the concept of living design, where biology becomes a crucial tool in the designer's toolkit [1]. This synergy between design and biology has given rise to “scientific design”, which “embraces scientific knowledge and works with new materials [2]. Scientific design involves a scientific approach based on research-creation. It represents a shift from object design to scientific creation, from agency to laboratory [2]. The objective extends beyond direct engagement with living organisms, it aspires to position a novel form of life at the core of design, fostering a new symbiosis with the surrounding environment and nature. These approaches involve treating the living as models, collaborators, and hackable systems for redesign, envisioning new life forms crafted by designers [3]. The designer-biologist, leveraging an interdisciplinary approach, possesses the capacity to create Hybrid Nature, Synthetic Nature, and Natural Nature. This growing synergy plays a pivotal role in the ecological transition towards “naturalizing” design [4]. The naturalization process aims to design new life forms by probing emerging systems of relationships around living entities, embodying the essence of this approach and establishing profound connections between the design object and its environment.

2.2 Inventing «Material Ecology»: Creating in Harmony with Natural Systems

The scientific designer aspires to explore a system of relationships that guides “living” matter to generate a material intricately interwoven with its environment. This perspective fortifies and reimagines the connection between design and nature, fostering the evolution of alternative, living, and intelligent materials. This interaction seeks to facilitate the seamless integration of these materials into the environment through the emergence of a new vital synergy, termed by Neri Oxman as Material Ecology [5]. Oxman defines it as a design philosophy, a research domain, and a scientific approach that delves into, elucidates, and expresses the relationships between the building, its environment, and its enhancement [6]. The underlying objective is to cultivate deeper connections between the design object and its environment while promoting an interrelation between buildings and the natural environment.

2.3 Living Design at the Center of a Regenerative and Sustainable Approach

Indeed, by integrating the living organism at the center of design processes, bio-design is moving more and more to create symbiosis with the nature. In this context, the biologist designer Carole Collet has defined living design as an approach to design based on a living system that integrates the learning from natural sciences and humanity in the service of regenerating biodiversity, climate, and communities [7]. Designers explore new strategies and aim to co-create with nature, actively participating in the preservation of local biodiversity while positioning humans as biological entities. This moves our frame of discourse from doing things TO nature’ to one of participation as partners WITH and AS nature, promoting a regenerative approach [8]. Living design encourages a multi-species approach contributing to the regeneration of natural, social, and economic systems. It plays a key role in the ecological transition by creating strategies and materials that value nature rather than exploit it. Through the illustration (Fig. 1), we aimed to demonstrate how living design can offer new perspectives and solutions for a more sustainable future, in harmony with nature.

Fig. 1.

Synthetic diagram: Living Design for a Regenerative and Sustainable Approach (made by the author).

3 When Eutrophication Inspires Bio-Design: Towards a Regenerative Approach in Tunis: Sfax

The exploitation of marine microorganisms, particularly algae, as a raw material is not a recent development. It has been utilized in various fields such as agriculture, food, cosmetology, and the creation of innovative design objects. Many bio-designers have now integrated algae as a central and fundamental element of their creations, using this resource as an architectural medium and building material. Aiming to valorize nature rather than consume it, in this experiment, we focused on co-fabrication with Ulva algae, classified as green macroalgae, which can become a marine hazard due to their proliferations but have the potential to be exploited as an organic resource in design conception (see Fig. 2).

Fig. 2.

Eutrophication: Proliferation of green algae on the surface of the sea at Sidi Mansour, May 10, 2023. (taken by the author)

Building on an interdisciplinary approach, our reflection aims not only to develop a biomaterial but also to create a proactive scenario for future habitats, fostering continuous interaction with the environment. Our objective is to encourage a multi-species approach with a salutogenic intention.

3.1 Idea Projection

While green algae do not exhibit intrinsic toxicity and are even edible, their environmental impact is indirect and associated with their growth rate [9]. Given their abundance in our natural ecosystem, we aimed to transform this naturally occurring phenomenon that can be harmful to the local environment into a resource for creating sustainable construction materials.

We attempted to convey our reflections and the proposed regenerative perspectives through the following diagram (see Fig. 3). We have developed a construction material using local algae and silica-rich sand, with the goal of creating a material that has positive systemic impacts on natural, economic, and social aspects.

Fig. 3.

Mental Map (made by the author)

3.2 Preparation and Experimental Testing

In our pursuit to determine how these algae could be applied in creating a lively and regenerative material, we conducted a variety of tests and experiments.

Step 1: Examining the optimal condition for integrating ulva algae into construction material design. This step involved conducting experiments with various forms of algae to assess their response to a new environment. Our observations suggest that the dry powder form of Ulva algae is more suitable for material design, exhibiting reduced vulnerability to degradation and mold formation compared to other forms.

Step 2: Exploring the optimal percentage of ulva powder to add to sand.

To determine the optimal composition of the mixture and the ideal concentration of Ulva algae in relation to silica sand, compression tests were conducted on specimens with varying algae concentrations (see Table 1).

Table 1. The different percentages of test specimens for the compression test. (Percentages are based on volume, not mass).

The specimens measured 70 mm in diameter and 140 mm in height [10] (refer to Fig. 4).

Fig. 4.

Specimens with a diameter of 70 mm and a height of 140 mm, featuring various percentages of Ulva for the compression test (taken by the author).

The purpose of this test was to generate stress/strain curves to assess the influence of adding algae powder, with the T0 specimen (containing 100% sand and 0% algae) serving as a reference (see Fig. 5).

Fig. 5.

Stress-strain curves of various specimens with different percentages of Ulva algae.

Upon analyzing these curves, depicted in Fig. 5, it was evident that the linear region was more pronounced for the T1 specimen containing 50% Ulva algae, displaying an elastic limit of 0.2 MPa. This indicates that the T1 sample had a higher capacity to withstand applied loads, demonstrating enhanced elasticity with an elastic modulus of approximately 3 MPa. However, the T2 and T3 specimens, with concentrations of 70% and 90% Ulva algae, resulted in a decrease in both maximum strength and elastic modulus compared to other specimens. These findings highlight that the 50% concentration significantly influences strength properties compared to our T0 reference, and the excessive increase of Ulva algae in the T3 specimen adversely affects the mechanical properties of the sample. In this context, the optimal formulation for our mixture involves considering Ulva algae powder as a reinforcing binder that enhances the stiffness of the specimen.

Step 3: Evaluating the impact of end-of-life ulva blocks on the natural ecosystem and local biodiversity.

To accomplish this, we conducted experiments with two aquarium fish, providing 2g of our material every other day. The fish flourished for over a month and a half, displaying sustained activity (see Fig. 6). This emphasizes the material's ability to supply nutrients (due to its high protein and mineral content) and establish a favorable environment for marine life.

Fig. 6.

Health and well-being of aquarium fish fed ulva-based material (taken by the author).

4 Advancing Toward a Circular Economy

These results reveal promising prospects for the potential implementation of our methodology in human creation. Bearing this in mind, a close collaboration has been initiated with the local company “SOIB” for the design of compacted blocks incorporating Ulva. These blocks are intended for use in the sustainable construction sector as part of a regenerative approach. Derived from the composition of SOIB's blocks and following numerous experiments, we created a block with the composition outlined in Table 2.

Table 2. The Composition of Ulva Seaweed Blocks Manufactured by the SOIB Company

As depicted in Fig. 7, our blocks are manufactured using the specific mold from the company SOIB, with dimensions of 22 cm width, 23 cm length, and 11.5 cm height. This morphology ensures precise interlocking of the blocks [11].

Fig. 7.

Example of our Ulva building blocks (taken by author).

Our emphasis is on creating positive impacts on both natural and socio-economic systems, fostering a circular economy. Our approach strives to improve the entire socio-ecosystem by encouraging the generation of local employment, revitalizing local communities, and regenerating life-support systems and their underlying resources, rather than depleting or altering them (Fig. 8).

Fig. 8.

Production of blocks using Ulva at a local company ‘SOIB’.

5 Conclusion

Through direct engagement with living organisms, our experimental approach is designed to co-create with nature, emphasizing the valorization of natural resources over their exploitation. Our methodology prioritizes a multi-species approach, focusing on bio-integrity rather than anthropocentrism. Positioned between cultivation and fabrication, our framework is rooted in genuine material ecology, reintegrating our buildings and their components into their environment. It envisions a future where life seamlessly integrates with the built environment, and the built environment enhances life. We also aim to showcase the feasibility of utilizing living organisms, specifically Ulva algae, in the creation of alternative construction materials while highlighting challenges related to its physicochemical properties. This leads us to explore intrasectoral approaches to develop holistic solutions aimed at enhancing its insulation, strength, and rigidity. Although the materialization of nature-aligned construction blocks is still in the conceptual phase in terms of materiality, its functional process suggests a future where nature can reclaim its place, thanks to the potential of Living Design.