As industries worldwide continue to seek more sustainable and innovative solutions, the field of geotechnical engineering is undergoing a transformative shift. Dr. Reena Hora is a Senior Geotechnical Engineer at Tetra Tech Coffey, is helping to drive sustainability in geotechnical engineering through her research into alternative microbial technologies.
Recently presenting her PhD research on the effects of soil grading on the unconfined compressive strength (UCS) of Microbially Induced Calcite Precipitation (MICP)-treated sandy soils at the prestigious International Conference on Microbial Biotechnology in Construction Materials and Geotechnical Engineering in Singapore, Reena highlighted the emerging potential of microbial technologies. The conference not only served as a platform for sharing cutting-edge research but also fostered global collaboration, bringing together experts in microbial technologies applied to civil and geotechnical engineering.
With her hands-on expertise and new insights gained, Reena is poised to drive forward innovative approaches that blend environmental sustainability with engineering excellence. As the industry evolves, the application of microbial techniques like MICP and Enzyme-Induced Calcite Precipitation (EICP) represents a key step towards sustainable infrastructure development. Here she shares her insights into this emerging approach to soil strengthening.
Harnessing microbial technology for soil strengthening: The role of particle size in MICP-treated soils
In an era where sustainability drives innovation, the use of eco-friendly technologies like Microbial Induced Calcite Precipitation (MICP) is gaining traction in geotechnical engineering. MICP uses naturally occurring bacteria to precipitate calcium carbonate in soil, creating a cement-like bond between soil particles, thereby enhancing its strength.
While the benefits of MICP are well-documented, previous research largely overlooked the role that particle size plays in the effectiveness of this bio-cementation process. This is what motivated further research by Reena and colleagues to explore critical aspect of MICP. This groundbreaking technique has the potential to revolutionize soil stabilization methods, especially for construction and infrastructure projects.
Key insights
The research team experimented with three different types of sand, each with varying particle size distributions, to determine how these differences impact Unconfined Compressive Strength (UCS)—a key measure of soil stability. Their findings were revealing:
Particle size matters: Smaller particles lead to stronger MICP-treated soils, especially when combined with higher levels of calcium carbonate precipitation. The size of the particles, measured by a parameter called d10, was found to be a crucial factor in the performance of the treated soil.
Predictive models for practical use: The study developed an empirical model that correlates particle size, calcium carbonate content, and UCS. This model, while still in its early stages, offers a promising tool for predicting soil behaviour in real-world applications.
Leading the way in sustainable construction
This research highlights a critical advancement in our understanding of MICP-treated soils, emphasizing the need to consider particle size in soil stabilization projects. As MICP technology continues to evolve, it holds significant promise for reducing the environmental footprint of construction projects by offering an efficient, low-impact method for improving soil strength.
With further refinement, this empirical approach could pave the way for more precise engineering solutions, transforming the way we think about and implement sustainable infrastructure. As the world looks for greener construction alternatives, MICP, backed by data-driven insights like those from Hora’s study, positions itself as a leader in the field of bio-geotechnical innovation.
By combining cutting-edge microbial science with practical engineering insights, we move closer to a future where sustainable, resilient infrastructure is not just possible, but the standard.
Connect with Dr. Reena Hora, Senior Geotechnical Engineer at [email protected]
Dr Hora’s paper was published in the Biogeotechnics Journal in October 24. The online journal aims to publish original studies on the experimental and theoretical aspects of bio-mediated and bio-inspired solutions in the geotechnical system, including laboratory and field testing, computational methods, design principles and site investigation. Read the full paper here: Evaluating the effect of soil grading on the UCS of MICP-treated sandy soils – ScienceDirect