Design of concrete face sandy gravel dam for Nazixia Hydropower Station

The Nazixia Hydropower Station is located at the end of the upstream of Datong River in Qinghai Province. With the severe cold climate, the altitude of the dam site exceeds 3000 m and the depth of river bed cover is between 18 m and 21 m. With the maximum dam height of 121.5 m, a concrete face sandy gravel dam is adopted for water-retaining. Here the layout of dam, dam zoning, design of dam construction materials, structure of toe slab and structure design of peripheral joint are described in detail, and special study is made not only on the treatment measures of the toe slab on river bed overburden layer but also on the structure characteristics of the seepage cutting by impermeable wall. Meanwhile, a useful exploration is carried out on building high concrete face sandy gravel dam on overburden layer. The structure design of the dam can be referenced by other similar projects.