某水电站堆积体成因机制及影响因素分析

西南某水电站坝址左岸发育一大型堆积体，方量约200×10^4m^3。该堆积体沿SWW方向呈喇叭形展布，边界较为清楚，主要物质组成为碎（块）石土及碎石夹粉质粘土。目前堆积体上可见开挖造成的局部垮塌现象，其整体稳定性与否将对坝线选择及水库的安全运营造成严重影响。本文在对其基本特征及变形破坏模式深人调查研究的基础上，探讨了其成因机制和影响因素，为进一步评价该堆积体的稳定性提供了坚实基础。

THE ANALYSIS OF INFLUENCING FACTORS AND FORMATION MECHANISM OF DEPOSIT BODY AT A HYDROPOWER STATION

The deposit body on the left bank o5 dam at a hydropower station in southwest China affects the safety of dam, which volume is about 2 million m3. It spreads along the SWW direction like a bugle with a clear boundary, which main material composition is made up of rubble and silty clay. Now there is some collapse in part of body by excavating. The choice of dam location and the security operation are seriously affected by its stability. Based on the investigation and research about the basic characteristics and the pattern of deformation and failure, the formation mechanism and influencing factors are analysed in this article. The results of this research will provide powerful basis to the stability evaluation..