Cost-plus-time bidding process where each contractor includes a time cost bid along with their construction bid and the contractor selected has the lowest combined bid total.

American Association of State Highway and Transportation Officials

The ratio of the weight referred to a vacuum of a given volume of material at a stated temperature to the weight referred to a vacuum of an equal volume of gas-free distilled water at the same temperature.

The displacement volume of an ingredient of concrete or mortar; in the case of solids, the volume of the particles themselves, including their permeable or impermeable voids but excluding space between particles; in the case of fluids, the volume which they occupy.

The moisture held in a material and having physical properties not substantially different from those of ordinary water at the same temperature and pressure.

Water held on surfaces of a material by physical and chemical forces, and having physical properties substantially different from those of absorbed water or chemically combined water at the same temperature and pressure.

The amount of water absorbed under specific conditions, usually expressed as a percentage of the dry weight of the material; the process by which the water is absorbed.

Increase in rate of hardening or strength development of concrete.

An admixture which, when added to concrete, mortar, or grout, increases the rate of hydration of hydraulic cement, shortens the time of set, or increases the rate of hardening or strength development.

Asphalt Concrete; asphalt pavement

Asphalt Concrete Hot Mix; asphalt pavement

American Concrete Institute

American Concrete Pavement Association

Alkali-Carbonate Reaction

The loss of bond between a joint sealant material and the concrete joint face noted by physical separation of the sealant from either or both joint faces.

The group of materials used to join or bond similar or dissimilar materials; for example, in concrete work, the epoxy resins.

A material other than water, aggregates, and portland cement (including air-entraining portland cement, and portland blast furnace slag cement) that is used as an ingredient of concrete and is added to the bath before and during the mixing operation.

Development at the surface of a solid of a higher concentration of a substance than exists in the bulk of the medium; especially in concrete and cement technology, formation of a layer of water at the surface of a solid, such as cement, or aggregate, or of air-entraining agents at the air-water boundaries; the process by which a substance is adsorbed.

Granular material, such as sand, gravel, crushed stone, crushed hydraulic-cement concrete, or iron blast furnace slag, used with a hydraulic cementing medium to produce either concrete or mortar.

The process of intermixing two or more aggregates to produce a different set of properties, generally, but not exclusively, to improve grading.

The distribution of particles of granular material among various sizes, usually expressed in terms of cumulative percentages larger or smaller than each of a series of sizes (sieve openings) or the percentages between certain ranges of sizes (sieve openings). See also "Grading."

The projection of aggregate particles or portion of aggregate particles from one side of a joint or crack in concrete into recesses in the other side of the joint or crack so as to effect load transfer in compression and shear and maintain mutual alignment.

Aggregate particles that possess well-defined edges formed at the intersection of roughly planar faces.

See Coarse Aggregate

Aggregates graded to produce low void content and maximum weight when compacted.

See Fine Aggregate

Aggregate so graded that certain intermediate sizes are substantially absent.

Aggregate of high density, such as barite, magnetite, hematite, limonite, ilmenite, iron, or steel, used to produce heavyweight concrete.

Aggregate of low density, such as (a) expanded or sintered clay, shale, slate, diatomaceous shale, perlite, vermiculite, or slag; (b) natural pumice, scoria, volcanic cinders, tuff, and diatomite; (c) sintered fly ash or industrial cinders, used to produce lightweight concrete.

See Maximum Size of Aggregate

In specifications for and descriptions of aggregate, the smallest sieve opening through which the entire amount of the aggregate is permitted to pass; sometimes referred to as "maximum size (of aggregate)."

Concrete aggregate in which the voids are relatively large when the aggregate is compacted.

See Cement-Aggregate Ratio

The rate of rotation of the drum or blades of a truck mixer when used for agitation of mixed concrete.

A vehicle in which freshly mixed concrete can be conveyed from the point of mixing to that of placing; while being agitated, the truck body can either be stationary and contain an agitator or it can be a drum rotated continuously so as to agitate the contents.

The process of providing gentle motion in mixed concrete just sufficient to prevent segregation or loss of plasticity.

A device for maintaining plasticity and preventing segregation of mixed concrete by agitation.

The amount of air in mortar or concrete, exclusive of pore space in the aggregate particles, usually expressed as a percentage of total volume of mortar or concrete.

A space in cement paste, mortar, or concrete filled with air; an entrapped air void is characteristically 1 mm or more in size and irregular in shape; an entrained air void is typically between 10 m and 1 mm in diameter and spherical (or nearly so).

The capabilities of a material or process to develop a system of minute bubbles of air in cement paste, mortar, or concrete during mixing.

An addition for hydraulic cement or an admixture for concrete or mortar which causes air, usually in small quantity, to be incorporated in the form of minute bubbles in the concrete or mortar during mixing, usually to increase its workability and frost resistance.

A cement that has an air-entraining agenda added during the grinding phase of manufacturing.

The inclusion of air in the form of minute bubbles during the mixing of concrete or mortar.

A device for measuring the air content of concrete and mortar.

A high-velocity jet of air and water mixed at the nozzle, used in clean up of surfaces of rock or concrete, such as horizontal construction joints.

Chemical reaction in mortar or concrete between alkalis (sodium and potassium) released from portland cement or from other sources, and certain compounds present in the aggregates; under certain conditions, harmful expansion of the concrete or mortar may be produced.

The reaction between the alkalies (sodium and potassium) in portland cement binder and certain carbonate rocks, particularly calcite dolomite and dolomitic limestones, present in some aggregates; the products of the reaction may cause abnormal expansion and cracking of concrete in service.