深水抛石防渗围堰的设计

摘要

Donghu power plant water intakes located in the reservoir has been built on the shore ,where the design of the cofferdam deep water regions ,reaching 31.6m over cofferdam filling holes using the drill and blast excavation carried throwing gravel fill construction ,the presence of stone weir overhead structure ,porosity larger and larger part of the stone,using high-pressure jet grouting,grout and other conventional plastic ce-ment grouting cofferdam breath is difficult to achieve the effect.Therefore ,the need to study seepage new tech-nology,designed to be adopted pasty slurry cement grout curtain grouting combined program,quality inspec-tion,and after filling the late cofferdam safety monitoring,the project cofferdam seepage curtain grouting per-formance to meet the design requirements ,description using slurry with cement grout slurry paste program combines practical,impervious type arrangement is reasonable,to provide a reference for other projects.%东湖电站取水口位于已建水库岸边，设计围堰所在区域水位较深，达到31.6m以上，围堰填筑采用钻爆法洞挖石渣进行抛填施工，堰体存在块石架空结构，孔隙率较大，且部分块石体积较大，采用高喷灌浆、塑性灌浆等常规水泥灌浆很难达到围堰防渗闭气效果。因此，需研究防渗新技术，设计拟采用膏状浆液结合水泥浆液的帷幕灌浆方案，经灌后质量检查以及后期围堰运行安全监测，本工程围堰灌浆帷幕防渗性能满足设计要求，说明采用膏状浆液与水泥浆液相结合的灌浆方案可行，防渗型式布置合理，为其他工程提供了借鉴和参考。