淤积作用下小浪底坝基F1断层带渗流演变规律与预测研究OA

The F1 fault zone of the Xiaolangdi Reservoir serves as the main water-conducting structure,and its seepage field characteristics directly affect the long-term safety of the project.The sediment deposition and compaction caused by long-term reservoir operation have signif-icantly altered the seepage conditions of the dam foundation.Based on engineering investigation and design data,measured reservoir sedimen-tation data,and monitoring results from piezometers and seepage flow meters in the F1 fault zone,this study systematically evaluated the seepage state and safety risk of the fault zone.A three-dimensional refined seepage numerical model incorporating the fault,clay core,dam foundation rock mass,and reservoir bottom sediments was established to analyze the spatiotemporal evolution of the seepage field in the F1 fault zone and reveal the influence mechanism of sedimentation on the seepage characteristics of the fault.The results indicate that:The cur-rent seepage condition of the F1 fault zone is generally stable and controllable.The thickening of reservoir bottom sediments effectively extends the seepage path and reduces the seepage pressure in the fault zone,demonstrating a significant inhibiting effect of sedimentation on fault leakage.In the future,with further development of sedimentation,the seepage pressure in the fault is expected to continue showing a slight decreasing trend.