The design of geyeyan gravity arch dam featuring an upper gravity dam and lower arch dam with crowned top

To adapt to the special physical conditions of the Geheyan dam site, dam designers conducted a number of comparative studies on the schemes of arch dams with flat top or crowned top, especially in cases of the latter using method of multiple arches and cantilevers in conjunction with 3-D FEM analysis and structural model tests. The shape of an upper gravity dam resting upon a lower arch dam with crowned top was finally adopted. Since it's impoundment in April 1994 the dam has been in operation with excellent performance, as demonstrated by safety monitoring data.