Abstract:

The dam foundation of Jiangbian hydropower station is composed of deep riverbed overburden. Its maximum depth is about 110 m. The layers of the overburden are obvious. The materials are mostly Quaternary alluvial-diluvial and colluvium formation. They are highly permeable. Permeability of the layers are quite different and their penetration are not stable. In order to ensure the seepage control structure safe, reliable and economical, based on study of the permeability of the covering layer, several treatment options for selection have been developed. By comparison, a cut-off wall 5-m deep into the sandy silt layer is adopted.

Key words: Jiangbian hydropower station, overburden, seepage control, cutoff wall

摘要： 江边水电站拦河坝基础覆盖层深厚，最大深度约110 m。基础覆盖层分层明显，床质多为第四系冲洪积、冲湖积、崩坡积地层，属中等-强透水层，各层的渗透性差异较大，渗透稳定性较差。为确保防渗结构安全、可靠、经济合理，在对覆盖层的渗透特性进行研究的基础上，拟定了多个处理方案进行比选，最终选择了防渗墙插入砂质粉土层5 m的方案。

关键词: 江边水电站, 覆盖层, 防渗处理, 防渗墙