HD水电站坝基扬压力分析及监控指标拟定

Formulation of Monitoring Indicators and Analysis of Uplift Pressure on the Dam Foundation of HD Hydropower Station

针对HD水电站坝基扬压力监测资料,采用定性和定量相结合的方法对扬压力进行深入分析,并根据置信区间法和典型小概率法拟定了监控指标。结果表明,各测点实测扬压力水位极值与年变幅相对稳定,扬压力水位均在设计范围内,帷幕防渗效果较好;坝基扬压力逐步回归统计模型精度较高,坝基扬压力受上游水位分量、下游水位分量和时效分量影响较大,受温度分量和降雨分量影响较小;典型小概率法拟定的监控指标略大于置信区间法和历史最大值。

Based on the monitoring data of uplift pressure on the dam foundation of HD hydropower station,this article adopts a combination of qualitative and quantitative methods to conduct in-depth analysis of uplift pressure,and formulates monitoring indicators based on confidence interval approach and typical small probability method.The results show that the measured extreme values and annual variation amplitude of the uplift pressure water level at each measuring point are relatively stable,and the uplift pressure water level is within the design range.The curtain anti-seepage effect is good.The stepwise regression statistical model for the uplift pressure of the dam foundation has high accuracy.The uplift pressure of the dam foundation is greatly affected by the upstream water level component,downstream water level component,and time effect component,while it is less affected by the temperature component and rainfall component.The monitoring indicators formulated by the typical small probability method are slightly larger than the confidence interval method and historical maximum values.