Ma Hao, Chen Youliang, Chang Lixin, Du Xi, Fernandez-Steeger Tomas Manuel, Wu Dongpeng, Azzam Rafig, Li Yi
Department of Civil Engineering, School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093, China.
Institute of Architectural Engineering, Shanghai Zhongqiao Vocational and Technical University, Shanghai 201514, China.
Materials (Basel). 2024 Apr 11;17(8):1747. doi: 10.3390/ma17081747.
This study investigates the dynamics of moisture absorption and swelling in soft rock during tunnel excavation, emphasizing the response to support resistance. Utilizing COMSOL numerical simulations, we conduct a comparative analysis of various strength criteria and non-associated flow rules. The results demonstrate that the Mohr-Coulomb criterion combined with the Drucker-Prager model under compressive loads imposes stricter limitations on water absorption and expansion than when paired with the Drucker-Prager model under tensile loads. Restricted rock expansion leads to decreased horizontal displacement and ground uplift, increased displacement in the tunnel's bottom arch, and significantly reduced displacement in the top arch. The study also considers the effects of shear dilation, burial depth, and support resistance on the stress and displacement of the surrounding rock. Increased shear dilation angles correlate with greater rock expansion, resulting in increased horizontal displacement and ground uplift. The research study concludes that support resistance is critical in limiting the movement of the tunnel's bottom arch and impacting the stability of the surrounding rock. Additionally, the extent of rock damage during the excavation of expansive soft rock tunnels is found to be minimal. Overall, this study provides valuable insights into the processes of soft rock tunnel excavation and contributes to the development of more efficient support systems.
本研究调查了隧道开挖过程中软岩吸湿和膨胀的动力学，重点关注其对支护阻力的响应。利用COMSOL数值模拟，我们对各种强度准则和非关联流动法则进行了对比分析。结果表明，在压缩荷载下，莫尔-库仑准则与德鲁克-普拉格模型相结合时，对吸水和膨胀的限制比在拉伸荷载下与德鲁克-普拉格模型相结合时更为严格。岩石膨胀受限导致水平位移和地面隆起减小，隧道底拱位移增加，顶拱位移显著减小。该研究还考虑了剪胀、埋深和支护阻力对围岩应力和位移的影响。剪胀角增大与岩石膨胀加剧相关，导致水平位移和地面隆起增加。研究得出结论，支护阻力对于限制隧道底拱的移动和影响围岩稳定性至关重要。此外，发现膨胀性软岩隧道开挖过程中的岩石损伤程度最小。总体而言，本研究为软岩隧道开挖过程提供了有价值的见解，并有助于开发更高效的支护系统。
