High Performance Concrete Specifications and Practices for Bridges (2013)

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37 Abrasion resistance—ability of a surface to resist being worn away by rubbing and friction. Alkali-silica reaction (ASR)—the reaction between the alkalies (sodium and potassium) in portland cement and certain siliceous rocks or minerals, such as opaline chert, strained quartz, and acidic volcanic glass, present in some aggregates; the products of the reaction may cause abnor- mal expansion and cracking of concrete in service. Autogenous shrinkage—change in volume produced by con- tinued hydration of cement, exclusive of effects of applied load and change in either thermal condition or moisture content. Binary concrete mix—concrete containing two cementitious materials. Chloride penetration—extent to which chlorides penetrate concrete. Compressive strength—the measured maximum resistance of a concrete specimen to axial compressive loading; expressed as force per unit cross sectional area. Corrosion resistance—resistance of metal to destruction by chemical, electrochemical, or electrolytic reaction within its environment. Creep—time-dependent deformation due to sustained load. Drying shrinkage—shrinkage resulting from loss of moisture. Flowability—ability of fresh concrete to flow into place. Freeze-thaw resistance—ability of concrete to withstand cycles of freezing and thawing. Heat curing—a system in which temperature is maintained in freshly placed concrete by supplying heat generated by steam or electrical heaters. Internal curing—a process by which hydration of cement and pozzolanic reactions continue because of an internal water source in addition to the mixing water. Match curing—a system in which concrete specimens are cured at the same temperature as that measured in a con- crete member. Modulus of elasticity—the ratio of normal stress to cor- responding strain for tensile or compressive stress below the proportional limit of the material. Performance specification—a specification in which the requirements are stated in terms of results with criteria for verifying compliance rather than specific composition, design, or procedure. Permeability—property of allowing passage of fluids. Plastic shrinkage—shrinkage that takes place before cement paste, mortar, grout, or concrete sets. Prescriptive specification—a specification that defines the means and methods of construction including composition of the concrete mix. Rapid chloride permeability—an electrical indication of concrete’s ability to resist chloride ion penetration. Scaling resistance—ability of a hardened concrete surface to resist disintegration and flaking, frequently caused by freeze-thaw cycles and application of deicing chemicals. Sulfate resistance—ability of concrete to withstand sulfate attack. Surface resistivity—measurement of resistance between two locations on the same concrete surface. Ternary concrete mix—concrete containing three cementi- tious materials. GLOSSARY