In the quest for sustainable construction materials, rammed earth (RE) has emerged as a frontrunner, offering a low-carbon alternative to conventional concrete. However, its susceptibility to water absorption has long been a Achilles heel, limiting its widespread adoption, particularly in energy infrastructure where durability is paramount. But a groundbreaking study led by Neha Vivek A. from the Department of Civil Engineering at B.M.S. College of Engineering, Bengaluru, India, published in Heliyon, has shown that bacteria might hold the key to unlocking RE’s full potential.
The study, titled “Microbially induced stabilized rammed earth: Compressive strength-capillary water absorption Co-relationship,” explores the use of Microbially Induced Calcium Carbonate Precipitation (MICP) to enhance the properties of cement-stabilized RE. The process involves bacteria that precipitate calcium carbonate, effectively filling the pores in RE and reducing capillary water absorption. This not only boosts the material’s compressive strength but also extends its lifespan, making it a more viable option for construction projects.
“MICP technique not only enhances the strength but also fills pores, inhibiting capillary water absorption thereby extending the lifespan of RE,” says Neha Vivek A. This is a significant finding, as increased cement content, while enhancing strength, does not effectively fill pores, leaving RE vulnerable to water damage.
The results of the study are promising. Tests on MICP-induced specimens indicated that the compressive strength increased by an average of 26%. Moreover, the capillary water absorption reduced considerably with the bacterial induction. This correlation between compressive strength and capillary water absorption could pave the way for more durable and sustainable construction materials.
The implications for the energy sector are substantial. Energy infrastructure, from power plants to wind farms, often requires robust, durable materials that can withstand harsh environmental conditions. RE, with its enhanced properties, could provide a more sustainable solution, reducing the carbon footprint of these projects. Furthermore, the potential to extend the lifespan of RE structures could lead to significant cost savings in maintenance and replacement.
While further study is necessary for microbial stabilization to be used in RE, these preliminary data show promising results. The research opens up new avenues for exploration, such as optimizing the MICP process for different soil types and environmental conditions. It also raises intriguing questions about the potential of other biological processes in enhancing construction materials.
As the construction industry continues to seek sustainable solutions, this research offers a glimpse into a future where bacteria could play a pivotal role in shaping our infrastructure. The study, published in Heliyon, a peer-reviewed journal, underscores the importance of interdisciplinary research in driving innovation in the construction sector.