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This state-of-the-art report outlines the historic background of the development of expansive cement concretes abroad and in this country, presents the relevant nomenclature, and summarizes the current status of expansive cements in the United States. The hydration chemistry of expansive cements is described, with emphasis on the components necessary for the formation of ettringite. The important factors in the choice of proportioning of materials are discussed, as well as the products of reaction, and heat of hydration. Various factors are discussed, which influence the rate and amount of expansion of all three types of expansive cement concretes. These include the chemical com-position, fineness and age of cement, water-cement ratio, mixing time, admixtures, aggregates, curing, temperature, restraint, and size and shape of specimens. The properties of expansive cement concretes are reported separately for shrinkage-compensating and self-stressing concretes. The properties considered in-clude workability, bleeding, time of setting, unit weight and yield, expansion, creep, shrinkage, compressive and bond strengths, modulus of elasticity, Poisson's ratio, coefficient of thermal expansion, and the resistance to various actions (deicer scal-ing, sulfate attack, cracking, and abrasion). Properties are also indicated on which no data are available at present. Field performance of shrinkage-compensating concrete is summarized. The in-fluences of restraint, aggregates, additives, ambient temperatures, forms, consistency, finishing, and curing are discussed. Examples of structural installations are presented, which include flat slabs, one-way pan joists, and two-way waffle slabs for parking garages, a folded plate roof for a bank, topping on a prestressed single tee parking deck structure, grade slabs and tilt-up panel walls for a department store, and an industrial floor. Five highway installations are described, including various spacings of contraction joints, continuously reinforced pavement as well as an unreinforced one, an application of self-stressing concrete, and the use of two bridge decks. The results of 17 tests on laboratory made structural elements of self-stressing concrete are summarized. These include tests on pipes, slabs, beams, frames, columns, and hyperbolic paraboloid. A brief review is given of some overseas experience. Needed areas of research and development are discussed with respect to expansive cements, material properties and behavior, and applications. An extensive bibliography is presented. [ABSTRACT FROM AUTHOR]

This guide summarizes the present state of the technology. It presents and interprets the data on lightweight aggregate concretes from many laboratory and field sources. These include the comprehensive studies at the University of Illinois in 1931, the parallel investigations by the U.S. Bureau of Reclamation and the National Bureau of Standards in 1949, numerous recent laboratory studies, accumulated experience resulting from greatly increased and successful use, and performance of structural lightweight aggregate concrete in service. The guide is intended for the architect, engineer, contractor, concrete producer, and student. It includes a definition of lightweight aggregate concrete for structural purposes; it discusses in condensed fashion the production methods and inherent properties of lightweight aggregates for structural concrete. This is followed by current practices on proportioning, mixing, transporting, placing; properties of hardened concrete; and finally, the design of structural concrete, with special reference to the 1963 ACI Building Code. [ABSTRACT FROM AUTHOR]