关角隧道断层地应力特征与应用

摘要

基于关角隧道实测地应力数据,文章采用有限元多元回归法和有限元改进型BP神经网络法拓展得到三维区域宏观地应力场,分析了地应力的三维分布规律.结果表明,关角隧道所穿越多处断层位置处地应力值偏高,侧压力系数偏大.考虑到其可能对隧道设计和施工产生影响,进一步分析了隧道穿越断层过程中的地应力分布规律.结果表明,地应力沿隧道穿过断层的里程呈现两头小、中间大规律,应力分布明显受断层构造的影响而存在一定的偏压现象.研究成果是后续一系列科研、设计和施工的重要基础,通过优化设计和施工措施,关角隧道大变形地段均得到有效控制.%Based on measured in-situ geostress data,a three-dimensional geostress field is obtained by the finite element multiple regression and finite element improved BP neural network methods,and the three-dimensional dis-tribution law of in-situ stress is analyzed.The results show that the geostress value and the lateral pressure coeffi-cient of the fault are somewhat high.Considering potential influences on tunnel design and construction,the geo-stress distribution rules are analyzed for the excavation of a tunnel passing through a fault.The results show that the distribution rule of geostress along the length of the tunnel in the fault is similar to the normal curve,the stress distri-bution is obviously affected by the fault structure and asymmetric pressure occurs.These research findings are an important foundation for future scientific research,design and construction,and ultimately deformation of the Guan-jiao tunnel was effectively controlled by optimizing design and construction measures.