台阶法施工时台阶长度对富水隧道稳定性影响研究

Influence of Bench Length in Benching Excavation on Stability of Tunnels in Water⁃Rich Ground

为提高富水隧道条件下台阶法施工效率,以小麻柳尾矿库主隧道工程为例,根据工程实际情况构建三维数字模型,进行流固耦合分析,分别模拟长台阶法、短台阶法以及微台阶法隧道施工过程。在此基础上,根据施工后隧道渗流场、位移场、应力场及塑性区分布情况分析不同台阶法施工效果,以CRITIC算法对其进行综合评价。结果表明,微台阶法更适于富水条件下隧道工程施工,其次为长台阶法,短台阶法施工效果较差。

In order to improve the construction efficiency in benching excavation for tunnels in water-rich ground,a main tunnel of Xiaomaliu tailings pond was taken as an example in the study.A three-dimensional digital model was constructed according to the actual situation of the project,and the fluid-structure interaction analysis was conducted by simulating benching excavation with three types of bench length.Then,the effect of benching construction with different bench length was analyzed in terms of seepage field,displacement field,stress field and plastic zone distribution of tunnel after construction,and a comprehensive evaluation was presented by using CRITIC algorithm.Results show that excavation with micro bench can bring the best construction effect for the tunnel in water-rich ground,followed by excavation with long bench,and excavation with short bench presents poor effect.