technical paper 39 Historical Development of Arch Dams: from cut-stone arches to modern concrete designs * H Chanson and OP James Dept of Civil Engineering, The University of Queensland, Brisbane QLD 4072 SUMMARY: Dn111 designs may be divided into three 111nin types: gravity structures relying on their weight for stability, arch structures using the abutment reaction forces and buttress da111s. Tlze design of an arch dam relies on the abut111ent reaction forces to resist the water pressure force and it requires advanced engineering expertise. The present study demonstrates that the historical development of arch da111s took pince in five stages. The world's oldest arch da111s were built by the Romans in France and Spain. They were followed by the Mongols who built da111s in Iran duri11g the 13th and 14th centuries. However ii is not until the 19th century that significant progress in arch da111 design was 111ade. Four re111arkable structures were the Meer Allum dam (India 1804), the Jones Falls dam (Canada 1831), the Zola dam (France 1854) and Parramatta dam (Australia 1856). Australian engineers pioneered tlze use of concrete as a construction material for arch dams (ie. 75-Miles and Lit'1gow No. 1 dams). Modern concrete arch da111 designs were i11troduced i11 North America at the begin11i11g of tl,e 20th century: eg. constn11t-a11gle arch, double- curvature arch. Since then 110 major design breakthrough !,as taken place and modern arch dams are based upon the si11gle-radi11s, co11stnnt-n11gle or double-rnrvnture arch design. It is the writers' opi11io11 that the introduction of concrete as construction 111a/erial marked n major innovation in allowing a flexibility in arch shape design. NOTATION E dam base thickness (m); e dam crest thickness (m); H dam height above foundation (m); L arch darn cr est length (m) R radius of curvature (m) of arch wall; 0 arch opening angle; 1 INTRODUCTION Dam designs may be divided into three main types: gravity structures relying on their weight for stability, arched structures using the abutment reaction forces and buttress dams. Historically, the first dams were earthfill and rockfill embankments, eg. Sadd-EI- Kaffara (Egypt BC 2800-2600), Marib ( Yemen BC 750), Panda Wewa (Sri Lanka BC 400-300), Cornalvo (Spain AD 150-200), see figure l. Concrete and stone masonry dams, commonly called gravity dams, were built at sites where good quality stones were Paper C20/006 submitted 22/05/00 Paper accepted for publication 20/03/02 © lnsti/11/ion of Fngineer~, Austrnlia 2002 available, eg. Khosr River (lrak BC 694), Al-Harbaqa (Syria AD 132), Kasserine (Tunisia AD 100-200). Sometimes, the dam wall was reinforced by masonry buttresses, eg.Alcantarilla (Spain BC 200-100), Proserpina (Spain AD 130).Later designs included arch dams, relying on the abutment reaction forces to resist the resulting water pressure force. A related design is the multiple-arch buttress dam, consisting of a series of arches supported by buttresses. Smith 1 and Schnitter 2 presented comprehensive treatises on the history of dam s. However, arch dam design was rare up to the late 19th century and the historical development of such dams received less attention, with one notable exception. 3 The present work will sh ow that the historical development of arch dams progressed during fi ve periods: the Roman arch dams (1st centuries BC and AD), the Mongol dams (14 and 15th centuries), some advanced masonry dams in the early 19th century (1804-1856), the Australian concrete arch dams (1880- 1896) and the modem arch shapes at the beginning of the 20th century (1903-1928). A11stralia11 Civil Engineering Transactions , Vol. CE43