Abstract: In plugging of construction drainage pipe of Three Gorges hydropower station, it is characterized by large buried depth, long distance and small space for operation. In this project, it is necessary to keep relatively smooth of grouting material in pipe outlet, and to fill well under certain pressure difference. Due to the irreversibility of plugging, failing to full closure at one time would leave a major hidden danger to dam's safe operation. According to the actual situation of the project, the required characteristics of grouting material are studied. The reliability of material and construction technology are verified by material development and field model simulation test. On this basis, single-point and long-distance backfill plugging is successfully carried out.

Key words: remote backfill grouting, thixotropy, crack filling, pipe filling, fault filling

摘要： 三峡电站施工期排水管封堵工程存在埋深大、距离长、可操作空间狭小等特点。如何实现灌注材料在管道下游出口相对畅通，且在有一定压差的情况下，克服管道阻力、填充密实，暂无类似工程项目可以借鉴。由于封堵施工的不可逆性，一旦不能一次性封堵到位，将给大坝的安全运行留下重大隐患。针对项目特殊情况，对封堵材料需具备的特性进行研究，通过材料研发、现场模型模拟试验来验证材料及工艺的可靠性，最终顺利实施了单点长距离回填灌注封堵。

关键词: 远距离回填灌浆, 触变性, 裂缝填充, 管道填充, 断层填充