三门峡水电站改建后,共安装容量为5万千瓦的低水头轴流转浆式机组5台。在施工过程中,为了加快进度,减少工艺困难,经试验研究,对水轮机组座环蜗壳反弧段(见图1)采用预填骨料灌浆工艺回填,收到了较好的效果。反弧段的混凝土,直接承受机组的荷重,是关系机组安全运行的重要部位。混凝土的设 Sanmenxia Hydropower Station after the rebuild, a total installed capacity of 50000 kilowatts of low-head axial-jet unit 5. In the process of construction, in order to speed up the progress and reduce the process difficulty, after the test and study, the reverse arc section of the seat ring ring of the hydro-turbine block (see Figure 1) was backfilled by the pre-filled aggregate grouting process and received good results. Anti-arc section of the concrete, the unit directly bear the load, is an important part of the safe operation of the unit. Design of concrete