刘家峡水电站主坝Ⅶ坝段幕前实测扬压力系数长期大于设计值,引起有关方面对坝前泥沙淤积层的防渗作用问题的关注。本文结合工程地质及帷幕施工等情况,对坝基扬压力的长期实测资料进行分析,表明泥沙淤积层的防渗作用是肯定的,但其具体效果受到基岩渗透性能和帷幕质量的影响。 The measured typhoon coefficient in front of the main dam section Ⅶ of Liujiaxia Hydropower Station was longer than the designed value for a long time, which aroused the concern of the parties concerned on the seepage control effect of the sediment layer before the dam. Based on the engineering geology and the construction of the curtain, the long-term measured data of the dam foundation uplift pressure are analyzed. The results show that the anti-seepage effect of the sediment layer is affirmative, but the concrete effect is affected by the permeability of the bedrock and the curtain quality.