深埋隧道软弱围岩交叉段围岩变形和压力特征分析

Study on Deformation and Pressure Characteristics of Surrounding Rock at the Cross Section of Weak Surrounding Rock

摘要: 为了揭示深埋隧道主洞与横通道交叉段围岩的变形和压力特征，为深埋隧道交叉段支护结构设计和施工控制提供依据，采用现场监测和数值模拟方法对深埋隧道交叉段围岩位移和压力及初期支护应力进行了分析。结果表明，深埋隧道横通道的开挖对交叉段的围岩位移和压力产生了显著的影响，并使得交叉段的围岩产生偏压；交叉段水平收敛和拱顶下沉表现为初期变形量大，变形发展快，变形持续时间长；围岩压力表现为初期来压快、压力大、持续时间长；横洞的开挖对交叉段主洞最大主应力和剪应力的影响较大，对最小主应力影响较小。分析结论对深埋隧道交叉段的设计和施工具有参考价值。

Abstract: In order to reveal the deformation and pressure characteristics of the surrounding rock at the in-tersection of the deep tunnel and the cross channel, and to provide a basis for the design and con-struction control of the supporting structure at the intersection of the deep tunnel. The on-site monitoring and numerical simulation methods were used to analyze the surrounding rock dis-placement, pressure and stress characteristics at the crossing section of the deep buried tunnel. The results show that the excavation of the horizontal tunnel of the deep tunnel has a significant impact on the displacement and pressure of the surrounding rock of the intersection, and causes the surrounding rock of the intersection to be biased. The deformation of surrounding rock and the pressure of surrounding rock at the intersection have the characteristics of large initial defor-mation, rapid deformation development and long deformation duration. The excavation of the transverse hole has a greater impact on the maximum principal stress and shear stress of the main tunnel at the intersection, and has a smaller effect on the minimum principal stress. The analysis conclusions are of reference value for the design and construction of deep-buried tunnel crossing sections.