A new numerical simulation method developed to tackle jamming issues faced by Double Shield Tunnel Boring Machines (TBMs) during tunneling through weak zones showcases the potential for enhancing construction efficiency and safety. These tunneling machines, integral to deep tunneling operations, frequently encounter challenges when passing through weak geological formations, leading to significant operational delays and safety risks.
This study emphasizes the importance of precisely modeling the interaction between TBM components and surrounding rock. Conducted as part of the DXL tunnel project located in Tibet, the research reveals insights gained from four significant jamming incidents experienced from August to October 2016. By utilizing advanced numerical simulation techniques, researchers offer strategies aimed at minimizing these disruptions.
The core of the analysis rests on the application of FLAC3D software, which facilitated the development of a finite difference model to simulate the mechanical responses of surrounding rock during TBM operations. Through these simulations, it becomes possible to quantitatively assess potential jamming scenarios based on varying geological conditions.
“The presence of weak zones in deep tunnels is one of the primary causes of TBM jamming,” the authors of the article state, underscoring the significance of the study. By depicting real-world incidences of machine jamming, such as the notable case at the K10 + 242 tunnel section, researchers highlight the necessity for innovative solutions to improve TBM excavation strategies.
Further illustrating the work carried out, the research provides detailed calculations of the thrust resistance and cutterhead torque levels experienced by the TBMs. “This numerical simulation method was applied to the shield jamming incident in the K10 + 242 section of the DXL tunnel,” the study explains, showcasing the reliability and accurate predictive capabilities of the simulation model.
The broad implications for tunneling operations extend beyond mere machine performance. By effectively anticipating the challenges posed by geological weaknesses, engineers can design more efficient tunneling approaches, thereby enhancing overall safety and ensuring timely project completions. The ultimate goal is to refine tunneling practices through data-backed approaches, which could lead to substantial advances within the field of geotechnical engineering.
Overall, this study not only addresses existing challenges but also lays the groundwork for future research, emphasizing the need to ponder factors like TBM advance rates and rock strata characteristics for continual improvement of tunneling strategies.