cools and cures. Types Constant radii arch dam the upstream face of the dam has a constant radius making it a linear shape face throughout the height of the dam. But the inner curves their radius reduces as we move down from top elevation to bottom and thus in cross-section it makes a shape of the triangle. Variable arch dam the radius of both inner and outer faces of the dam arch varies from bottom to top. The radius of the arch is greatest at the top and lowest at lower elevations. The central angle of the arch is also widened as we move upside. Constant angle arch dam this is the most economical in construction. However, for the third type of arch dam stronger foundation is required as it involves overhangs at the abutment sections. The constant angle arch dam is that in which the central angles of the horizontal arch rings are of the same magnitude at all elevations. Examples of arch dams Buchanan Dam (example of multiple-arch type) Contra Dam Daniel-Johnson Dam Deriner Dam El Atazar Dam Enguri Dam Flaming Gorge Dam Glen Canyon Dam Hartbeespoort Dam Idukki Dam Kariba Dam Karun-3 Dam Luzzone Dam Mauvoisin Dam Mratinje Dam New Bullards Bar Dam Pensacola Dam St. Francis Dam Victoria Dam Xiluodu Dam Hoover Dam Bhumibol Dam See also Arch-gravity dam Gravity dam Parabolic arch References External links PBS.org: Dam Basics Historical Development of Arch Dams. From Cut-Stone Arches to Modern Concrete Designs Key Developments in the History of Arch Dams, from archive.org Dams by type Arches and vaults . Concrete buildings and structures Masonry dams