material / concrete / admixture
material / concrete / aggregate
material / concrete / cement
material / concrete / chemical
material / concrete / component
material / concrete / fault
material / concrete / finish
material / concrete / form
material / concrete / mix
material / concrete / mortar
material / concrete / plasticity
material / concrete / process
material / concrete / property
material / concrete / type
material / concrete / admixture
- accelerator: An admixture that hastens the setting and strength development of a concrete, mortar, or plaster mix.
- air-entraining agent: An admixture that disperses entrained air in a concrete or mortar mix to increase workability, improve resistance of the cured product to the cracking induced by free-thaw cycles or the scaling caused by deicing chemicals, and in larger amounts, to produce lightweight insulating concrete.
- coloring agent: A pigment or dye added to a concrete mix to alter or control its color.
- retarder: An admixture that slows the setting of a concrete, mortar, or plaster mix in order to allow more time for placing and working the mix.
- superplasticizer: An admixture for reducing the amount of mixing water required for the desired workability of a concrete or mortar mix. Lowering the water-cement ratio in this manner generally results in increased strength. Also called superplasticizer.
- surface-active agent: An admixture for reducing the surface tension of the mixing water in a concrete mix, thereby facilitating the wetting and penetrating action of the water or aiding in the emulsifying and dispersion of other additives in the mix.
- surfactant: An admixture for reducing the surface tension of the mixing water in a concrete mix, thereby facilitating the wetting and penetrating action of the water or aiding in the emulsifying and dispersion of other additives in the mix.
- water-reducing agent: An admixture for reducing the amount of mixing water required for the desired workability of a concrete or mortar mix. Lowering the water-cement ratio in this manner generally results in increased strength. Also called superplasticizer.
material / concrete / aggregate
- aggregate: A material, usually sand or gravel, this is mixed with water and cement to make concrete.
- coarse aggregate: Aggregate consisting of crushed stone, gravel, or blast-furnace slag having a particle size larger than 1/4 inch (6.4 mm): specifically the portion of aggregate that is retained on a No. 4 (4.8 mm) sieve. The maximum size of coarse aggregate in reinforced concrete is limited by the size of the section and the spacing of the reinforcing bars.
- exfoliation: The splitting or swelling of certain minerals into a scaly aggregate when heated.
- expanded clay: A strong lightweight aggregate obtained by the exfoliation of slate.
- expanded shale: A strong lightweight aggregate obtained by the exfoliation of slate.
- expanded slate: A strong lightweight aggregate obtained by the exfoliation of slate.
- exposed aggregate finish: A decorative finish produced by sandblasting, etching with an acid, or scrubbing a concrete surface after the initial set in order to remove the outer layer of cement paste and expose the aggregate.
- fine aggregate: Aggregate consisting of sand having a particle size smaller than 1/4 inch (6.4 mm): specifically the portion of aggregate that will pass through a 3/8 inch (9.5 mm) sieve, almost entirely through a No. 4 (4.8 mm) sieve, and be predominantly retained on a No. 200 (74u) sieve.
- graded aggregate: Aggregate having a particle-size distribution characterized by uniform grading. Graded aggregate requires the least amount of cement paste to fill the voids and surround the particles.
- pearlite: A volcanic glass expanded by heat to form lightweight, spherical particles, used as nonstructural lightweight aggregate and as loose-fill thermal insulation.
- perlite: A volcanic glass expanded by heat to form lightweight, spherical particles, used as nonstructural lightweight aggregate and as loose-fill thermal insulation. Also, pearlite.
- air-entraining portland cement: A Type I, Type II, or Type III portland cement to which a small quantity of an air-entraining agent has been interground during manufacture: designated by the suffix A, as Type 1A, Type IIA, or Type IIIA.
- cement: A powder of calcined (burned) rock or stone used to make concrete.
- cendree de tournai: A kind of hydraulic cement used in Belgium, composed of caustic lime from the Tournai limekilns and the slaty coal ashes left from the kiln fires. The lime is slaked by sprinkling with water, and the mixture, after being buried for some weeks, triturated, and dried, forms an excellent hydraulic cement.
- high-early-strength: Descriptive of a variety of Portland cement which attains more quickly the strength that ordinary cement and its concrete acquire in setting.
- hydraulic cement: Cement having the property of taking its set under water.
- marmoratum: In ancient Roman construction, a cement formed of pounded marble and lime mortar which were well mixed; used in build walls, terraces, etc.
- masonry cement: A proprietary mix of portland cement and other ingredients, as hydrated lime, plasticizers, air-entraining agents, and gypsum, requiring only the addition of sand and water to make cement mortar.
- mastic: A form of cement or calking compound that retains a measure of elasticity. 2. Any of various pasty substances used as a sealant, adhesive, or protective coating.
- natural cement: A naturally occurring clayey limestone which, when calcined and finely pulverized produces a hydraulic cement.
- Parker’s cement: Grey-brown stucco rendering composed of burnt-clay nodules crushed to powder and mixed with lime, sand, and water. Patented 1796, sometimes known as Roman or Sheppey cement, it hardened quickly and was commonly applied to inferior brickwork facades as a substitute for ashlar, the ‘joints’ suggested by scores made before the cement dried. It was also used (without the addition of lime) for construction under water, as it had the peculiar property of hardening in such conditions: it was superseded by Portland cement.
- pebbledash: Cement with pebbles applied before dries.
- Portland cement: A hydraulic cement binder for concrete; made by burning a mixture of clay and limestone.
- pozzolan cement: A siliceous or siliceous and aluminous material, which in itself possesses little or no cementitious value but will, in finely divided form and in the presence of moisture, chemically react with calcium hydroxide at ordinary temperatures to form compounds possessing cementitious properties.
- pozzuolana: Variety of volcanic sand with burnt granules resembling powdered brick: it is a siliceous or siliceous and aluminous material which, when mixed with hydraulic limes and water, becomes a cement-like compound capable of setting under water…
- pozzuolana cement: A siliceous or siliceous and aluminous material, which in itself possesses little or no cementitious value but will, in finely divided form and in the presence of moisture, chemically react with calcium hydroxide at ordinary temperatures to form compounds possessing cementitious properties.
- puzzolana: Variety of volcanic sand with burnt granules resembling powdered brick: it is a siliceous or siliceous and aluminous material which, when mixed with hydraulic limes and water, becomes a cement-like compound capable of setting under water…
- puzzolano: Also see pozzolan.
- rendering cement: A tough and strong cement plaster, taking the place of lime and hair mortar in the plastering of walls and ceilings, not liable to crack or swell, capable of being applied directly to a surface of masonry or laths, and not needing finish coats; it has the property of drying and hardening rapidly.
- Roman cement: A quick-setting natural cement; a hydraulic cement or hydraulic lime; unknown to the early Romans.
- Rosendale cement: A light hydraulic cement.
- tabby: A cement made of oyster shells and lime.
- tarras: A strong cement formerly used in hydraulic engineering. 2. An ancient spelling of terrace.
- white portland cement: A portland cement produced from raw materials low in iron oxide and manganese oxide, the substances that give concrete its gray color: used in precast concrete work and in the making of terrazzo, stucco, and tile grout.
material / concrete / component
- caementum: Same as cenaculum.
- chamfer strip: A strip of wood or other material attached to a form to produce a smooth, rounded or beveled edge on the outside corner of a concrete member.
- dicalcium silicate: A compound constituting about one-quarter of the volume of portland cement and responsible for the aging or long-term gain in strength of the cement.
- keyway: A longitudinal groove or channel formed in a concrete footing or other member that has set, providing a shear-resisting key for newly placed concrete. 2. A slot in a lock for receiving and guiding a key.
- parting compound: Any of various materials, as oil or silicone for preventing the bonding of concrete to a surface.
- release agent: Any of various materials, as oil or silicone for preventing the bonding of concrete to a surface. Also called parting compound.
- rustication strip: A strip of wood or other material attached to the inside face of a form to produce a groove in the surface of a concrete member.
- siliceous: Containing silica or a silicate.
- stiffback: A vertical support for aligning and reinforcing wales.
- strongback: A vertical support for aligning and reinforcing wales. Also called stiffback.
- tricalcium aluminate: A compound constituting about one-tenth of the volume of portland cement and responsible for the initial setting of the cement.
- tricalcium silicate: A compound constituting about half the volume of portland cement and responsible for the hardening or early gain in strength of the cement.
- whaler: Also see waler.
- crazing: Numerous hairline cracks occurring in the surface of a newly hardened concrete slab as a result of rapid drying shrinkage.
- honeycombing: A common fault in concrete: voids caused by incomplete filling of the form.
- laitance: A frothy, gelatinous deposit occurring on the top surface of cement or concrete, caused by an excess of water in the mixture.
- scaling: The chipping or scaling of a hardened concrete or masonry surface caused by freeze-thaw cycles or the application of deicing salts. 2. The ascertaining of dimensions from a proportional drawing by comparison with a scale.
- spalling: The chipping or scaling of a hardened concrete or masonry surface caused by freeze-thaw cycles or the application of deicing salts. Also called scaling.
- stratification: The separation of an excessively wet or overvibrated concrete mix into horizontal layers with increasingly lighter material migrating toward the top.
- sulfate action: An expansive reaction occurring when the cement matrix of concrete or mortar comes in contact with sulfates dissolved in ground water or in soil.
- béton: Concrete. Béton brut is a raw concrete exposed after the formwork is struck, sometimes showing impressions of the timber boards of which formwork is constructed.
- béton brut: Used to describe concrete left in its natural state upon removal of formwork; beton brute is literally ‘concrete in the raw’.
- broom finish: A striated finish obtained by stroking a broom or stiff brush over a freshly troweled concrete surface.
- brushhammered finish: A coarse-textured finish obtained by fracturing a concrete or stone surface with a power-driven hammer having a rectangular head with a corrugated, serrated, or toothed face.
- bushhammered finish: A coarse-textured finish obtained by fracturing a concrete or stone surface with a power-driven hammer having a rectangular head with a corrugated, serrated, or toothed face.
- dry-shake finish: A colored finish produced by sprinkling a dry mixture of cement, sand, and a pigment on a fresh concrete surface following screeding and after any free water has evaporated, and then working the mixture into the surface with a float.
- float finish: A fine-textured finish obtained by smoothing a fresh concrete, plaster, or stucco surface with a wood float.
- form liner: Material for lining the inside face of a form, specially selected to impart a smooth or patterned finish to the concrete surface.
- power trowel: A portable machine having steel trowels mounted on radial arms that rotate about a vertical shaft to smooth, compact, and finish a fresh concrete surface.
- swirl finish: A textured finish given to a fresh plaster or concrete surface by troweling with a circular, overlapping motion.
- trowel finish: A dense, smooth finish obtained by working a fresh concrete or plaster surface with a steel trowel.
- workability: The relative ease with which freshly mixed concrete or mortar can be handled, placed in formwork, compacted, and finished. Workability depends partly on the water-cement ratio and partly on the grading or the aggregate in a mix.
- climbing form: A form that can be raised vertically for succeeding lifts of concrete during the construction of a multistory building.
- cone bolt: A form tie having cones at each end inside the forms which allow it to also serve as a spreader.
- flying form: A large form that can be moved by a crane, used in constructing the concrete floors and roofs of multistory buildings.
- form tie: A metal tie for keeping wall forms from spreading under the fluid pressure of newly placed concrete.
- formwork: A structure of wood (recently, sometimes of other materials) used to mold the surfaces of a concrete structure to the required shape and removed after the concrete has dried out.
- grade strip: A wood strip fixed to the inside face of a form to indicate the top of a concrete lift.
- she bolt: A form tie consisting of water rods which are inserted through the form and threaded onto the ends of an inner rod. After stripping, the water rods are removed while the inner rod remains in the concrete.
- slip form: A form that can be moved slowly and continuously as concrete is being placed during the construction of a concrete pavement or building.
- snap tie: A form tie having notches or crimps which allow its ends to be snapped off below the concrete surface after stripping of the forms.
- Sonotube: Trademark for a brand of cylindrical column form made of compressed, resin-impregnated paper.
- spreader: A brace, usually of wood, for spacing and keeping walls or footing forms apart. Also called spacer.
- wedge: Any of a variety of slotted devices for tightening formwork and transferring the force in a form tie to the walls.
- mix design: The most economical selection and proportioning of cement, water, and aggregate to produce concrete or mortar having the required properties of workability, strength, durability, and watertightness.
- mixing water: The water used in a concrete or mortar mix, exclusive of any absorbed by the aggregate and free of such harmful substances as organic material, clay, and salts. Water fit for drinking is generally acceptable.
- segregation: The separation of coarse aggregate from the mortar or of water from the other ingredients of freshly mixed concrete, resulting from excessive horizontal movement or free fall of the mix, or from overvibration after placement.
- uniform grading: A particle-size distribution in which aggregate particles vary uniformly from fine to coarse without a preponderance of any one size or group of sizes.
- dry mix: A concrete or mortar mix containing little water or too much aggregate in relation to the other components and having little or no slump. Also called stiff mix.
- fat mix: A concrete or mortar mix that is easy to work or spread because of a relatively high cement or lime content. Also called rich mix.
- lean mix: A concrete or mortar mix that is difficult to work or spread because of a shortness of cement or lime.
- plastic mix: A concrete or mortar mix that flows sluggishly without segregating and is readily molded.
- rich mix: A concrete or mortar mix that is easy to work or spread because of a relatively high cement or lime content. Also called rich mix.
- stiff mix: A concrete or mortar mix containing little water or too much aggregate in relation to the other components and having little or no slump.
- wet mix: A concrete or mortar mix having a relatively high water content and runny consistency, yielding a product that is low in strength, durability, and watertightness.
- granular material: Any gravel, sand, or silt that exhibits no cohesiveness or plasticity.
- plastic limit: The water content, expressed as a percentage of dry weight, at which a soil loses its plasticity and begins to behave as a solid.
- bull float: A float having a large, flat blade attached to a long handle.
- calcine: To heat a substance to a high temperature but without melting or fusing to drive off volatile matter or to cause oxidation or reduction.
- consolidation: The process of eliminating voids other than entrained air within newly placed concrete and ensuring close contact of the concrete with form surfaces and embedded reinforcement. 2. The gradual reduction in the volume of a soil mass resulting from the application of a sustained load and an increase in compressive stress.
- core test: A compression test of a cylinder cut from a hardened concrete structure, usually by means of a core drill.
- dry-pack: To ram a stiff, high-strength, low-shrinkage concrete or grout mix into a confined space, as under a bearing plate, to transmit a compressive load.
- edger: A trowel having a long, curved lip for rounding the edges of a fresh concrete slab as it begins to set.
- finishing: The process of leveling, smoothing, compacting, and treating a newly placed concrete surface to produce the desired texture and appearance.
- float: A mason’s tool, a flat board with handle on one side, used for spreading and smoothing plaster or cement. 2. A float valve.
- free fall: The descent of freshly mixed concrete into a form without the aid of a drop chute.
- hydration: The process in which a substance combines chemically with water, as that occurring when cement is mixed with water.
- rodding: The act of compacting freshly poured concrete in its form by freeing the mass of air pockets with repeated stabs of a rod; such compacting is now more efficiently done with a vibrator.
- set: The assumption of a rigid or hard state by concrete, mortar, plaster, or glue due to a physical or chemical change. 2. To sink a nailhead slightly below the surface with a nail set.
- sett: Same as set.
- slump cone: An open-ended, truncated cone of sheet metal 12 inches (305 mm) high, with a base diameter of 8 inches (203 mm) and a top diameter of 4 inches (102 mm), used to mold a specimen of freshly mixed concrete for the slump test.
- slump test: A method for determining the consistency and workability of freshly mixed concrete by measuring the slump of a test specimen.
- spading: Consolidation of newly placed concrete by the repeated insertions and withdrawals of a flat, spadelike tool.
- temper: To mix and blend lime, sand, and water, or cement, sand, and water, to make mortar. 2. To thin with water either of the above mixtures to make them workable – a practice usually forbidden in specifications. 3. To strengthen or toughen a metal by reheating at a lower temperature and slowly cooling the material.
- test cylinder: A cylinder of concrete 6 inches (152 mm) in diameter and 12 inches (305 mm) high, cast from a representative batch and cured in a laboratory or in the field under controlled conditions.
- abram’s law: A law postulating that, with given concrete materials, curing, and testing conditions, the compressive strength is inversely proportional to the ratio of water to cement: developed by D.A. Abrams in 1919 from experiments at Lewis Institute in Chicago.
- admixture: Any substance other than cement, water, or aggregate, added to a concrete or mortar mix to alter its properties or those of the hardened product. Also called additive.
- bag: A measure of portland cement: 94 lb in the U.S.; 87.5 lb. in Canada, 112 lb. in Britain, and 50 kg in countries using the metric system. Also called bag.
- cement content: The quantity of cement per unit of volume of concrete or mortar mix, preferably expressed in pounds per cubic yard but often stated in sacks of cement per cubic yard of mix.
- consistency: The relative ability of freshly mixed concrete or mortar to flow, usually measured by the slump test for concrete and by the flow test for grout or mortar. Consistency depends largely on the proportion of cement past to aggregate in a mix.
- cure: To maintain newly placed concrete or mortar at the required temperature and humidity for the first seven days following placement, casting, or finishing to ensure satisfactory hydration of the cementitious materials and proper hardening.
- direct placement: The discharging of freshly mixed concrete directly into a form from a concrete mixer, buggy, or crane bucket.
- drying shrinkage: A reduction in volume of concrete, mortar, or plaster caused by a loss of moisture.
- entrained air: Microscopic, spherical air bubbles, typically 0.004 to 0.04 inches (0.1 to 1.0 mm) in diameter, intentionally dispersed in a concrete or mortar mix by an air-entraining agent.
- heat of hydration: The heat generated by the process of hydration, as during the setting and curing of a concrete mix.
- partical-size distribution: The range of particle sizes in a granular material, expressed either as the cumulative percentage by weight of particles smaller or larger than a specified sieve opening, or as the percentage by weight of the particles that range between specified sieve openings.
- placement: The process of depositing and consolidating freshly mixed concrete in a form or in the final position where it is to harden.
- pneumatic placement: The delivery of concrete, slurry, or plaster by a pipeline or hose to the point of placement on a construction site, either in a plastic state for depositing in place or for spraying, or in a dry state with water added at the nozzle from which it is sprayed.
- sack: A measure of portland cement: 94 lb in the U.S.; 87.5 lb. in Canada, 112 lb. in Britain, and 50 kg in countries using the metric system. Also called bag.
- setting shrinkage: A reduction in volume of concrete prior to its final set, caused by hydration of the cement paste.
- slump: A measure of the consistency and workability of freshly mixed concrete expressed as the vertical setting, in inches, of a specimen after it has been placed in a slump cone, tamped in a prescribed manner, and the cone is lifted.
- time of haul: The period from first contact between mixing water and cement to completion of discharge of the freshly mixed concrete from a truck mixer.
- water content: The quantity of water per unit volume of concrete or mortar mix, preferably expressed in pounds per cubic yard but often stated in gallons per cubic yard of mix.
- water gain: The emergence of excess mixing water on the surface of newly placed concrete, caused by settlement of solids within the mass.
- water-cement ratio: The ratio of mixing water to cement in a unit of volume of concrete or mortar mix, preferably expressed by weight as a decimal fraction but often stated in gallons of water per 94-lb. sack of cement. The water-cement ratio controls the strength, durability, and watertightness of hardened concrete.
- adobe concrete: A mingled mass of stone and adobe mortar.
- aerated concrete: Cement-based insulating material commonly used in modern construction.
- architectural concrete: Exposed concrete work requiring special care in the selection of materials, forming, placing, and finishing to acquire the desired appearance.
- artistic concrete: concrete blocks molded to imitate stone, inexpensive substitute using concrete since 1870
- artistic concrete block: Inexpensive substitute for stone facing with a variety of surface textures. Due largely to quality control problems, imitation stone block fell out of favor as a cheap building material in the 1920s.
- board-marked concrete: See béton.
- cast-in-place concrete: Concrete deposited, formed, cured, and finished in its final position as part of a structure. Also called cast-in-situ concrete.
- cast-in-situ concrete: Concrete deposited, formed, cured, and finished in its final position as part of a structure.
- cellular concrete: Cement-based insulating material commonly used in modern construction.
- cinder concrete: A concrete utilizing boiler cinders for the coarse aggregate, in the effort to achieve lightness of weight, and incidentally a nailing surface.
- concrete: A mixture of cement, water, sand, and stones (called aggregate) which hardens to a stonelike consistency.
- gfrc: Glass Fiber Reinforced Concrete is a thin shell cast material making it lightweight. The addition of cast glass fibers [material made from extremely fine fibers of glass] acting as reinforcement creates durability without requiring embedded steel.
- granolith: A concrete used for paving, the coarse aggregate being pulverized granite.
- Gunite: Trade name for a concrete of grout consistency applied to its reinforcement through a hose, using compressed air.
- insulating concrete: Lightweight concrete having a unit weight of less than 60 pcf (960 kg/m3) and low thermal conductivity, made with lightweight aggregate, as perlite, or with a foaming agent or gas-forming chemical that infuses the mix with a homogenous cellular structure.
- lightweight concrete: Concrete that uses lightweight aggregates, generally produced by artificial means, to create a material having many of the properties of concrete but is appreciably lighter in weight.
- plain concrete: Concrete having no reinforcement, or reinforced only for drying shrinkage or thermal stresses.
- poured concrete: Concrete walls for foundation and above ground.
- precast concrete: Concrete cast in molds before being incorporated in a building.
- prestressed concrete: Type of reinforced concrete, in which steel bars are replaced by steel cables within ducts disposed to enable the tension areas of the concrete to be compressed by stretching them before loading. It allows for accuracy as well as economical use of both concrete and steel.
- Pulhamite: Blend of colored sand, Portland Cement, and industrial clinker applied to a core of rock and brick rubble, then tooled to look like natural rock…
- ready-mixed concrete: Concrete mixed at a batch plant for delivery by an agitator truck to a construction site.
- shotcrete: A lightweight concrete construction consisting of a mixture of cement, sand or crushed slag, and water, pumped through a hose and sprayed at high velocity over reinforcement until the desired thickness is reached.
- shrink-mixed concrete: Concrete partially mixed at a batch plant and then mixed more completely in a truck mixer en route to a construction site.
- structural lightweight concrete: Concrete made with strong lightweight aggregate, as expanded shale or slate, having a unit weight from 85 to 115 pcf (1362 to 1840 kg/m3) and compressive strength comparable to that of normal concrete.
- transit-mixed concrete: Concrete dry batched at a batch plant and mixed in a truck mixer en route to a construction site.
- Type I: normal: A portland cement used for general construction, having none of the distinguishing qualities of the other types.
- Type II: moderate: A portland cement having a reduced content of tricalcium aluminate, making it more resistant to sulfates and causing it to generate less heat of hydration: used in general construction where resistance to moderate sulfate action is required or where heat buildup can be damaging, as in the construction of large piers and heavy retaining walls.
- Type III: high early strength: A very finely ground portland cement having an increased content of tricalcium silicate, causing it to cure faster and gain strength earlier than normal portland cement: used when the early removal of formwork is desired, or in cold-weather construction to reduce the time required for protection from low temperatures.
- Type IV: low heat: A portland cement having a reduced content of tricalcium silicate and an increased content of dicalcium silicate, causing it to generate less heat of hydration than normal portland cement: used in the construction of massive concrete structures, as gravity dams, where a large buildup in heat can be damaging.
- Type V: sulfate resisting: A portland cement having a reduced content of tricalcium aluminate, lessening the need for gypsum, a sulfate normally added to cement to retard its setting time: used where resistance to severe sulfate action is required.
material / concrete / plasticity
material / concrete / property
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