隧洞典型断面围岩稳定性数值模拟研究与支护设计效果分析

隧洞开挖过程中,由于开挖卸荷及扰动的影响围岩出现大变形、局部塌方等工程地质灾害,严重威胁到施工安全及进度。本研究依托杨房沟水电站引水隧洞工程,选取了典型断面,开展了数值分析研究,获得了应力场、变形场和塑性区分布特征。通过有限元数值模拟方法,对不同类型围岩区隧洞开挖后围岩稳定性特征以及初期支护效果进行分析,为优化支护设计提供了合理的参数,为地下工程安全施工方案的制定提供了强有力的支撑。

Numerical Simulation Study on Stability of Surrounding Rock in Typical Section of Tunnel and Analysis of Designed Supporting Effect

Excavation unloading and disturbance induces engineering disaster such as large deformation and local collapse in surrounding rock,which seriously threatens the construction safety and influences construction progress.Relied on the selected sections of the headrace tunnel of Yangfanggou Hydropower Station,this study obtains the distribution characteristics of stress field,deformation field and plastic zone through numerical analysis.With the finite element numerical simulation method,the stability characteristics of surrounding rock and the initial support effect after tunnel excavation in different types of surrounding rock areas are analyzed,which provides reasonable parameters for optimizing the support design and provides support for working out safe construction scheme of underground engineering.