In the quest for sustainable construction materials, a groundbreaking study led by Arthur Lam from the ESTP-IRC Laboratory in Cachan, France, has shed new light on the potential of stabilized earth concretes. Published in the journal Buildings, the research delves into the mechanical, thermal, hygrothermal, and environmental properties of 12 different stabilized earth concrete formulations, offering insights that could revolutionize the energy sector and construction industry.
The study, which involved four types of excavated earths and three different binders, including low-carbon GGBS-based binders, reveals that stabilized earth concretes can achieve impressive thermal and hygrothermal properties while maintaining a low carbon footprint. “The results show that gravel-rich earths demonstrate higher densities and compressive strengths compared to fine-rich earths,” Lam explains. “This is a significant finding for the construction industry, as it highlights the potential for using locally sourced materials to create structurally sound and energy-efficient buildings.”
One of the most compelling aspects of the research is the comparison of different binders. The study found that GGBS-based binders, particularly those with sulfo-calcic activation, can significantly enhance the mechanical performance of earth concretes while keeping carbon emissions low. “Concretes made with LW binders showed superior mechanical performance and a lower normalized indicator for carbon emissions,” Lam notes. “This makes them an excellent choice for applications requiring higher strength and a low carbon footprint.”
The implications for the energy sector are profound. Buildings account for a significant portion of global energy consumption, and the use of stabilized earth concretes could help reduce this burden. By providing thermal inertia and humidity regulation, these materials can enhance indoor thermal comfort and reduce the need for heating and cooling. “The thermal conductivity and Moisture Buffer Value of these materials are consistent with raw earth values, supporting their potential use for energy-efficient and climate-adaptive construction,” Lam states.
Moreover, the study underscores the importance of considering the composition of earth materials in future formulations. The granular distribution and clay content play crucial roles in determining the mechanical and thermal properties of stabilized earth concretes. This knowledge could guide the development of new, more sustainable construction practices.
As the construction industry continues to seek ways to reduce its environmental impact, the findings of this study offer a promising path forward. By leveraging the natural properties of earth materials and optimizing the use of low-carbon binders, it is possible to create buildings that are not only structurally sound but also energy-efficient and environmentally friendly. The research published in Buildings provides a comprehensive framework for achieving these goals, paving the way for a more sustainable future in construction.