水工隧洞土洞段稳定性分析及支护效果研究

水工隧洞围岩的应力分布及变形特征对保证其长期稳定性具有关键的作用。该文以中部引黄施工支洞为例进行实态建模,通过利用有限差分程序FLAC3D进行分析计算。研究结果表明,未加强支护前,锁脚锚杆所受的压应力已超过锚杆的抗压强度,拱脚处应力集中现象明显;变形主要集中在拱顶、底板部位;加强支护后,钢拱架变形、钢拱架轴力和锚杆最大拉应力都得到减小。支护效果稳定且能够满足施工及后期运行要求。

Stability Analysis and Supporting Effect of the Earth Tunnel Section of Hydraulic Tunnel

The stress distribution and deformation features of hydraulic tunnel surrounding rock have a key role to ensure its longterm stability.This paper takes the Central Yellow River 12# construction branch tunnel as an example of real state modeling, by using finite element software FLAC3D Elasto-plastic Numerical.The results of the study show that, without reinforced support, the foot-lock bolt bears more compressive strength than the anchor, the stress concentration phenomenon is obvious at the arch foot;the deformation is mainly concentrated on the top and bottom parts;after reinforced support, steel arch deformation, steel arch axial force and bolt maximum tensile stress can be reduced.The supporting effect is stable and can meet the requirements of construction and later operation.