In the depths of the earth, where mining and energy extraction operations often take place, understanding the stability of rock formations is paramount. A recent study published in *Yantu gongcheng xuebao* (Chinese Journal of Geotechnical Engineering) sheds new light on this critical issue, offering insights that could significantly impact the energy sector. Led by Dr. Qin Changbing from Chongqing University, the research team has developed a novel approach to analyze the stability of deeply-buried cavities, considering the dynamic effects of vertical seismic forces.
The study employs the upper bound limit analysis method, which is widely used in geotechnical engineering to assess the stability of structures. However, what sets this research apart is its use of the nonlinear Baker criterion, a more versatile tool compared to the traditional Hoek-Brown and Mohr-Coulomb criteria. “The Baker criterion provides a more accurate representation of the failure behavior of rock and soil under different conditions,” explains Dr. Qin. “This allows us to better understand and predict the stability of deeply-buried cavities, which is crucial for the safety and efficiency of mining and energy extraction operations.”
The research team proposed a curved failure mechanism for roof collapse within the framework of the Baker criterion. They also considered the impact of vertical seismic loading, which is often overlooked in traditional stability analyses. “Seismic forces can significantly affect the stability of deeply-buried cavities,” says Dr. Qin. “By incorporating these forces into our analysis, we can provide a more comprehensive assessment of the potential risks.”
The team derived closed-form solutions for the failure surface, collapse height, and width, providing valuable insights into the behavior of deeply-buried cavities under different conditions. To validate their findings, they used ABAQUS modeling, a powerful finite element analysis software. The results of the parametric studies conducted as part of the research indicate that the upward seismic force has a significant effect on the failure region above the cavity roof, in addition to the properties of the rock and soil.
The implications of this research for the energy sector are substantial. By providing a more accurate and comprehensive assessment of the stability of deeply-buried cavities, it can help energy companies to optimize their operations, reduce risks, and improve safety. “This research has the potential to shape future developments in the field of geotechnical engineering,” says Dr. Qin. “It provides a new tool for analyzing the stability of deeply-buried cavities, which can be used to improve the safety and efficiency of mining and energy extraction operations.”
As the energy sector continues to evolve, the need for innovative solutions to the challenges of deep underground operations will only grow. This research represents a significant step forward in meeting that need, offering a new approach to analyzing the stability of deeply-buried cavities that could have far-reaching implications for the industry.