The Use of Prestressing and Precasting in Concrete Water Tanks and Towers in Britain and Ireland

This paper discusses the introduction of prestressing and the use of precasting of sections or segments in conjunction with prestressing, for the construction of concrete service water reservoirs and water towers, for purposes of public water supply in Britain and Ireland. Prestressing to combat hoop stress in cylindrical concrete tanks became permissible under the Water Retaining Code of Practice of 1938, but it was to be some years before the anchorage systems available allowed for its use in the construction of service water reservoirs. Since then, a number of systems and arrangements have been used successfully. Once the use of reinforced concrete became widespread for water tanks, it was necessary to ensure that the walls of water-retaining structures were always watertight. In the early 1900s a variety of techniques was employed to ensure that walls were watertight until it was realised that a good quality concrete, properly designed and mixed, should meet the requirement. By 1922, H.C. Ritchie, who later introduced his patent system of ‘reinforced steelwork’, was advocating the use of reinforced concrete for water-retaining structures, noting that: