某水电站尾水洞边坡稳定性三维数值模拟分析

3D Numerical Simulation Analysis for Stability of Tailwater Tunnel Slope of a Hydropower Station

某水电站尾水洞边坡在工程开挖后有多条缓倾坡外断层被切出坡面,稳定性状况恶化。为了准确评价这些断层的稳定性状况,以相互切割断层为边界建立地质模型,在地质模型的基础上建立三维数值模型,利用FLAC3D软件模拟边坡在工程开挖后应力应变的变化情况,进而评价边坡在开挖后的稳定性情况。最终结果显示边坡在开挖后处于欠稳定状态,为工程边坡后续的支护措施设计提供了依据。

After excavation ,there are some flat dipping faults cut out from the slope of a hydropower station ’s tailwater tunnel ,the stability condition is deteriorated .In order to evaluate the fault stability accurately ,the geological model is set up with the fault boundary cut each other ,and the 3D numerical model is set up on the basis of the geological model ;The FLAC3D software is used to simulate the changes of stress and strain after engineering excavation ,so as to evaluate the stability of the excavated slope .The final conclusion shows that the slope is in unstable state after excavation ,which would provide basis for the follow-up supporting measure design of engineering slopes .