秦岭北缘某深埋引水隧洞应力场特征研究

岩体初始地应力场是研究地下洞室围岩稳定状况和隧洞选线的重要依据。应用水压致裂法对秦岭北缘某深埋引水隧洞应力进行测定,结果显示隧洞围岩应力等级属于中低~高应力水平,应力量值呈σ_Hσ_hσ_z特征,最大水平主应力方向为近NE向,与区域构造主压应力方位接近一致。基于实测数据,对工程区应力场进行回归反演,并结合区域构造应力对隧道沿线的深埋和浅埋段应力场分布规律进行了研究,以期为引水工程的设计和施工提供参考。

Study on Stress Field Characteristics of A Deep Buried Diversion Tunnel in the Northern Margin of Qinling

The initial stress field of rock mass is an important basis for studying the stability of surrounding rock of underground caverns and selecting tunnel line.In-situ stress was tested by hydraulic fracturing method in a deep buried diversion tunnel in the northern margin of Qinling.The results show that the stress level of the surrounding rock of tunnel belongs to middle lower ～ high stress level,the feature of stress value should be σH ＞σh ＞ σz,and the maximum horizontal principal stress direction is NE and in close agreement with regional tectonic principal pressure.Based on the measured data,regression inversion was conducted in the stress field of project area.Combined with regional tectonic stress,the stress field distribution was studied in deep buried and shallow buried section along the tunnel in order to provide a reference for the design and construction of water diversion project.