In the quest to meet carbon peaking and neutrality goals, researchers have turned their attention to innovative technologies that can stabilize soft soil grounds while also contributing to carbon sequestration. A groundbreaking study led by GU Wenbo from the Institute of Geotechnical Engineering at Southeast University, in collaboration with colleagues from the Yellow River Institute of Hydraulic Research and the Research Center on Levee Safety & Disaster Prevention, has introduced a novel approach that combines electrochemical grouting with CO2 carbonation. This method not only strengthens soft soil foundations but also offers a promising solution for reducing carbon emissions in the construction industry.
The study, published in *Yantu gongcheng xuebao* (translated as “Chinese Journal of Geotechnical Engineering”), presents a method that injects CO2 gas into the soil during the electrochemical grouting process. This dual approach leverages the benefits of both electrochemical grouting and carbonation to enhance the strength of soft soil foundations rapidly and significantly. “The combined reinforcement of electrochemical grouting and carbonation for the soft soil foundation with depolarized CaCl2 solution and Na2SiO3 solution is better than the traditional electrochemical grouting stabilization method,” explains GU Wenbo, the lead author of the study. “The undrained shear strength of soil increases greatly, and the contribution of carbonation accounts for half of the total growth undrained shear strength.”
The researchers conducted laboratory model tests to compare the undrained shear strength of soil treated with the new method against traditional electrochemical grouting. They also measured soil conductivity and pH values during the stabilization process, demonstrating the superiority of the combined technology in strengthening soft soil grounds. Through scanning electron microscope tests, the study revealed the micro-cementation of soft soil after the combined treatment, shedding light on its micro-reinforcement mechanism.
The implications of this research are far-reaching, particularly for the energy sector. As infrastructure projects increasingly prioritize sustainability, technologies that can stabilize soft soil while also sequestering carbon will be in high demand. “This technology has both carbon sequestration and soft soil solidification effects, which is of great significance for the low-carbon development of foundation stabilization,” notes GU Wenbo.
The study’s findings suggest that the combined electrochemical grouting-carbonation method could become a standard practice in geotechnical engineering, offering a cost-effective and environmentally friendly solution for stabilizing soft soil grounds. As the construction industry continues to evolve, such innovations will play a crucial role in achieving carbon neutrality goals while ensuring the stability and safety of infrastructure projects.
In the words of the researchers, this technology represents a significant step forward in the field of geotechnical engineering, offering a sustainable and efficient solution for stabilizing soft soil grounds. As the world moves towards a low-carbon future, the combined electrochemical grouting-carbonation method could become a cornerstone of sustainable construction practices, shaping the future of the energy sector and beyond.