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Mass Concrete
Mass concrete is defined by American Concrete Institute Committee 207 as "any volume of concrete with dimensions large enough to require that measures be taken to cope with the generation of heat from hydration of cement and attendant volume change to minimize cracking."ACI Committee 207–Mass and Thermally Controlled Concrete As interior temperature of mass concrete rises due to the process of cement hydration, the outer concrete may be cooling and contracting. If the temperature differs too much within the structure, the material can crack. The main factors influencing temperature variation in the mass concrete structure are: the size of the structure, the ambient temperature, the initial temperature of the concrete at time of placement and curing program, the cement type, and the cement contents in the mix. Mass concrete structures include massive mat foundations, dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Concrete Institute
The American Concrete Institute (ACI, formerly National Association of Cement Users or NACU) is a non-profit technical society and standards developing organization. ACI was founded in January 1905 during a convention in Indianapolis. The Institute's headquarters are currently located in Farmington Hills, Michigan, USA. ACI's mission is "ACI develops and disseminates consensus-based knowledge on concrete and its uses." ACI History A lack of standards for making concrete blocks resulted in a negative perception of concrete for construction. An editorial by Charles C. Brown in the September 1904 issue of ''Municipal Engineering'' discussed the idea of forming an organization to bring order and standard practices to the industry. In 1905 the National Association of Cement Users was formally organized and adopted a constitution and bylaws. Richard Humphrey was elected its first President. The first committees were appointed at the 1905 convention in Indianapolis and offered prelimina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |