In the quest to stabilize and restore high, steep rock slopes, a team of researchers led by Dr. Shao Guanghui from Nanjing Forestry University has made a significant breakthrough. Their work, published in the Chinese journal *Yantu gongcheng xuebao* (translated as *Rock and Soil Engineering*), explores the use of microbial mortar to enhance the adhesion and stability of soil on rock surfaces, a critical challenge in ecological protection and infrastructure development.
The study focuses on the shear strength and cementation characteristics of the interface between microbial mortar and rock. Traditional methods like external-soil spray seeding (ESSS) often face issues with soil peeling off, but the application of microbial mineralization technology offers a promising solution. By forming a microbial mortar on the bare rock surface, the researchers aim to improve the bond between the soil substrate and the rock.
Dr. Shao and his team conducted interfacial shear tests on limestone cemented by microbial mortar. Their findings reveal that the cohesion and friction angle of the microbial mortar-rock interface can reach 45.6 kPa and 26.40 degrees, respectively. “The microbial cementation has few effects on the friction angle of the interface,” noted Dr. Shao, highlighting the stability of the bond. Additionally, when the calcium carbonate content exceeds 2.5%, the microbial mortar exhibits better water stability, a crucial factor for long-term durability.
The research also delves into the microscopic structure of the microbial mortar. “There are abundant pores in the microbial mortar overlying the rock surface,” explained Dr. Shao. The shear failure of the interface is primarily caused by the peeling of the contact surface between sand particles and calcium carbonate crystals, as well as the internal fracture of the calcium carbonate crystal aggregate.
The implications of this research are far-reaching, particularly for the energy sector. In areas where rock slopes are prevalent, such as in mining and oil extraction sites, the stability of these surfaces is paramount. The use of microbial mortar could significantly reduce the risk of landslides and soil erosion, enhancing the safety and longevity of infrastructure projects.
Dr. Shao’s work not only provides a scientific foundation for the application of microbial geotechnical technology but also opens up new avenues for innovation in the field. As the energy sector continues to expand into more challenging terrains, the need for stable and eco-friendly solutions becomes increasingly critical. This research offers a glimpse into the future of geotechnical engineering, where microbial technologies could play a pivotal role in ensuring the stability and sustainability of our infrastructure.
For professionals in the construction and energy sectors, this study underscores the importance of integrating advanced technologies to address long-standing challenges. As Dr. Shao and his team continue to explore the potential of microbial mortar, their work could pave the way for more resilient and environmentally friendly engineering practices.