西南某电站消力塘边坡雾化作用下的稳定性研究

 根据西南某在建水电站溢洪道泄洪消能雨雾的分布预测，消力塘开挖边坡将受强烈的雾化作用影响。通过消力塘边坡结构面组合和受力情况分析，认为该边坡在降雨条件下可能发生平推式滑动破坏。滑坡起动判据计算显示，边坡中以G222–2为底滑面、f556–1为后缘拉张裂缝的组合块体在拉裂缝中地下水位达772.1 m时，将首先发生平推式滑动破坏。由于该边坡地下水主要由降雨及雾化雨补给，因此建立了降雨补给下边坡潜水渗流模型，分析边坡内地下水位与降雨时间的关系。计算结果表明，暴雨对边坡持续作用260 h或者雾化叠加暴雨持续作用246 h后，边坡内地下水位达到起动判据的要求，平推式滑动破坏发生。建议实施坡面防护，阻断水与边坡岩体的相互作用，以保证该边坡的长期稳定。

RESEARCH ON STABILITY OF HYDROPOWER STATION PLUNGE POOL SLOPE AFFECTED BY ATOMIZATION-RAIN IN SOUTHWEST OF CHINA

The plunge pool slope of a hydropower station in construction in Southwest of China is influenced by atomization-rain according to the forecast distribution of atomization-rain caused by spillway flood discharge. The slope is liable to fail in the form of horizontal-push landslide on the condition of rainfall based on the research of fissures combination and forces loaded on them. The block in the slope，which is made up of G222–2 as bottom slip face and f556–1 as back tension fracture，is liable to slide when the underground water level is 772.1 m high according to the calculating results of the start criterion of horizontal-push landslide. A seepage model of the underground water in the slope on raining condition is established to analyze the relationship between underground water level，and the time of raining for the underground water mainly comes from rainfall and atomization-rain. Results of calculating show that the start criterion is reached if there are rainstorm over 260 hours or both rainstorm and atomization-rain over 246 hours. And the horizontal-push landslide is to happen. In order to keep the slope safe，measures such as slope protection should be taken to isolate the rock from water.