|
A |
|
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A+B Contract |
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. |
|
AASHTO |
American Association of State Highway and Transportation Officials |
|
Absolute Specific Gravity |
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. |
|
Absolute Volume (of ingredients of concrete or mortar) |
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. |
|
Absorbed Moisture |
The moisture held in a material and having physical properties not
substantially different from those of ordinary water at the same
temperature and pressure. |
|
Absorbed Water |
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. |
|
Absorption |
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. |
|
Acceleration |
Increase in rate of hardening or strength development of concrete. |
|
Accelerator |
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. |
|
ACI |
American Concrete Institute |
|
ACPA |
American Concrete Pavement Association |
|
ACR |
Alkali-Carbonate Reaction |
|
Adhesion Loss |
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. |
|
Adhesives |
The group of materials used to join or bond similar or dissimilar
materials; for example, in concrete work, the epoxy resins. |
|
Admixture |
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. |
|
Adsorption |
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. |
|
Aggregate |
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. |
|
Aggregate Blending |
The process of intermixing two or more aggregates to produce a
different set of properties, generally, but not exclusively, to improve
grading. |
|
Aggregate Gradation |
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." |
|
Aggregate Interlock |
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, Angular |
Aggregate particles that possess well-defined edges formed at the
intersection of roughly planar faces. |
|
Aggregate, Coarse |
See Coarse Aggregate |
|
Aggregate, Dense-graded |
Aggregates graded to produce low void content and maximum weight when
compacted. |
|
Aggregate, Fine |
See Fine Aggregate |
|
Aggregate, Gap-graded |
Aggregate so graded that certain intermediate sizes are substantially
absent. |
|
Aggregate, Heavyweight |
Aggregate of high density, such as barite, magnetite, hematite,
limonite, ilmenite, iron, or steel, used to produce heavyweight concrete. |
|
Aggregate, Lightweight |
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. |
|
Aggregate, Maximum Size |
See Maximum Size of Aggregate |
|
Aggregate, Nominal Maximum Size |
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)." |
|
Aggregate, Open-graded |
Concrete aggregate in which the voids are relatively large when the
aggregate is compacted. |
|
Aggregate-Cement Ratio |
See Cement-Aggregate Ratio |
|
Agitating Speed |
The rate of rotation of the drum or blades of a truck mixer when used
for agitation of mixed concrete. |
|
Agitating Truck |
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. |
|
Agitation |
The process of providing gentle motion in mixed concrete just
sufficient to prevent segregation or loss of plasticity. |
|
Agitator |
A device for maintaining plasticity and preventing segregation of mixed
concrete by agitation. |
|
Air Content |
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. |
|
Air Void |
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). |
|
Air-Entraining |
The capabilities of a material or process to develop a system of minute
bubbles of air in cement paste, mortar, or concrete during mixing. |
|
Air-Entraining Agent |
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. |
|
Air-Entraining Cement |
A cement that has an air-entraining agenda added during the grinding
phase of manufacturing. |
|
Air-Entrainment |
The inclusion of air in the form of minute bubbles during the mixing of
concrete or mortar. |
|
Air-Meter |
A device for measuring the air content of concrete and mortar. |
|
Air-Water Jet |
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. |
|
Alkali-Aggregate Reaction |
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. |
|
Alkali-Carbonate Reaction |
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. |
|
Alkali-Silica Reaction |
The reaction between the alkalies (sodium and potassium) in portland
cement binder and certain siliceous rocks or minerals, such as opaline
chert, strained quartz, and acisic volcanic glass, present in some
aggregates; the products of the reaction may cause abnormal expansion and
cracking of concrete in service. |
|
Alternate Lane Construction |
A method of constructing concrete roads, runways, or other paved areas,
in which alternate lanes are placed and allowed to harden before the
remaining immediate lanes are placed. |
|
Angle of Repose |
The angle between the horizontal and the natural slope of loose
material below which the material will not slide. |
|
Area of Steel |
The cross-sectional area of the reinforcing bars in or for a given
concrete cross section. |
|
Artificial Turf Drag |
Surface texture achieved by inverting a section of artificial turf that
is attached to a device that allows control of the time and rate of
texturing. |
|
Asphalt |
A brown to black bituminous substance that is chiefly obtained as a
residue of petroleum refining and that consists mostly of hydrocarbons. |
|
ASR |
See, Alkali-Silica Reaction |
|
ASTM |
American Society for Testing and Materials |
|
Automatic Batcher |
A batcher equipped with gates or valves which, when actuated by a
single starter switch, will open automatically at the start of the
weighing operation of each material and close automatically when a
designated weight of each material has been reached, interlocked in such a
manner that (1) the charging mechanism cannot be opened until the scale
has returned to zero, (2) the charging mechanism cannot be opened if the
discharge mechanism is opened, (3) the discharge mechanism cannot be
opened if the charging mechanism is opened, (4) the discharge mechanism
cannot be opened until the designated weight has been reached within the
allowable tolerance, and (5) if different kinds of aggregates or different
kinds of cements are weighed cumulatively in a single batcher, interlocked
sequential controls are provided. |
|
Axle Load |
The portion of the gross weight of a vehicle transmitted to a structure
or a pavement through wheels supporting a given axle. |
|
B |
|
|
Backer Rod |
Foam cord that inserts into a joint sealant reservoir and is used to
shape a liquid joint sealant and prevent sealant from adhering to or
flowing out of the bottom of the reservoir. |
|
Bag (of cement) |
A quantity of cement; 42.6 kg in the United States, 39.7 kg in Canada;
portland or air-entraining portland cement, or as indicated on the bag for
other kinds of cement. |
|
Ball Test |
A test to determine the consistency of fresh concrete by measuring the
depth of penetration of a steel ball. The apparatus is usually called a
Kelly ball. |
|
Bar |
A member used to reinforce concrete, usually made of steel. |
|
Bar Chair |
An individual supporting device used to support or hold reinforcing
bars in proper position to prevent displacement before or during
concreting. |
|
Bar Spacing |
The distance between parallel reinforcing bars, measured center to
center of the bars perpendicular to their longitudinal axis. |
|
Bar Support |
A rigid device used to support or hold reinforcing bars in proper
position to prevent displacement before or during concrete placing. |
|
Barrel (of cement) |
A unit of weight for cement: (170.6 kg) net, equivalent to 4 US bags
for portland or air-entraining portland cements, or as indicated by the
manufacturer for other kinds of cement. (In Canada, 158.8 kg. net per
barrel). |
|
Base |
A subfloor slab or "working mat," either previously placed
and hardened or freshly placed, on which floor topping is placed in a
later operation; also, the underlying stratum on which a concrete slab,
such as a pavement, is placed. |
|
Base Course |
A layer of specified select material of planned thickness constructed
on the subgrade or subbase below a pavement to serve one or more functions
such as distributing loads, providing drainage, minimizing frost action,
or facilitating pavement construction. |
|
Batch |
Quantity of concrete or mortar mixed at one time. |
|
Batch Plant |
Equipment used for batching concrete materials. |
|
Batch Weights |
The weights of the various materials (cement, water, the several sizes
of aggregate, and admixtures) that compose a batch of concrete. |
|
Batched Water |
The mixing water added to a concrete or mortar mixture before or during
the initial stages of mixing. |
|
Batching |
Weighing or volumetrically measuring and introducing into the mixer the
ingredients for a batch of concrete or mortar. |
|
Beam Test |
A method of measuring the flexural strength (modulus of rupture) of
concrete by testing a standard unreinforced beam. |
|
Benkelman Beam |
Static deflection measuring tool equipped with dial gauges able to
detect slab deflection to 0.025 millimeters. |
|
Binder |
See Cement Paste |
|
Bitumen |
Any of various mixtures of hydrocarbons (as tar) often together with
their non-metallic derivatives that occur naturally or are obtained as
residues after heat-refining petroleum |
|
Bituminous |
Resembling, containing or impregnated with bitumen. |
|
Blanking Band |
A plastic scale, or computer-generated scale, 1.7 inches wide and 21.12
inches long representing a length of 0.1 miles on a profilograph trace.
The opaque blanking strip, running the length of the scale and located at
its midpoint, covers the profile trace. Typically, a bandwidth of 0.0 to
0.2 in. is used. |
|
Blast Furnace Slag |
The non-metallic by-product, consisting essentially of silicates and
aluminosilicates of lime and other bases, which is produced in a molten
condition simultaneously with iron in a blast furnace. |
|
Bleeding |
The self-generated flow of mixing water within, or its emergence from,
freshly placed concrete or mortar. |
|
Bleeding Rate |
The rate at which water is released from a paste or mortar by bleeding,
usually expressed as cubic centimeters of water released each second from
each square centimeter of surface. |
|
Blemish |
Any superficial defect that causes visible variation from a
consistently smooth and uniformly colored surface of hardened concrete. (See
also Bug Holes, Efflorescence, Honeycomb, Laitance, Popout, Rock Pocket,
Sand streak.) |
|
Blended Cement |
See Cement, Blended |
|
Blended Hydraulic Cement |
See Cement, Blended |
|
Blistering |
The irregular rising of a thin layer of placed mortar or concrete at
the surface during or soon after completion of the finished operation. |
|
Bond |
The adhesion of concrete or mortar to reinforcement or other surfaces
against which it is placed; the adhesion of cement paste to aggregate. |
|
Bond Area |
The interface area between two elements across which adhesion develops
or may develop, as between concrete and reinforcing steel. |
|
Bond Breaker |
A material used to prevent adhesion of newly placed concrete from other
material, such as a substrate. |
|
Bond Hardness |
The support (bond strength) that the metal matrix in a diamond saw
blade segment provides to each diamond that is embedded within the matrix. |
|
Bond Strength |
Resistance to separation of mortar and concrete from reinforcing steel
and other materials with which it is in contact; a collective expression
for all forces such as adhesion, friction due to shrinkage, and
longitudinal shear in the concrete engaged by the bar deformations that
resist separation. |
|
Bond Stress |
The force of adhesion per unit area of contact between two surfaces
such as concrete and reinforcing steel or any other material such as
foundation rock. |
|
Bonded Concrete Overlay |
Thin layer of new concrete (2-4 inches) placed onto slightly
deteriorated existing concrete pavement with steps taken to prepare old
surface to promote adherence of new concrete. |
|
Bonding Agent |
A substance applied to an existing surface to create a bond between it
and a succeeding layer, as between a bonded overlay and existing concrete
pavement. |
|
Box Out |
To form an opening or pocket in concrete by a box-like form; Used for
manholes, drainage inlets and other in-pavement objects.. |
|
Broom |
The surface texture obtained by stroking a broom over freshly placed
concrete. A sandy texture obtained by brushing the surface of freshly
placed or slightly hardened concrete with a stiff broom. |
|
Bug Holes |
Small regular or irregular cavities, usually not exceeding 15 mm in
diameter, resulting from entrapment of air bubbles in the surface of
formed concrete during placement and compaction. |
|
Bulk Cement |
Cement that is transported and delivered in bulk (usually in specially
constructed vehicles) instead of in bags. |
|
Bulk Density |
The mass of a material (including solid particles and any contained
water) per unit volume, including voids. |
|
Bulk Specific Gravity |
The ratio of the weight in air of a given volume of a permeable
material (including both permeable and impermeable voids normal to the
material) at a stated temperature to the weight in air of an equal volume
of distilled water at the same temperature. |
|
Bulking Factor |
Ratio of the volume of moist sand to the volume of the sand when dry. |
|
Bull Float |
A tool comprising a large, flat, rectangular piece of wood, aluminum,
or magnesium usually 20 cm wide and 100 to 150 cm long, and a handle 1 to
5 m in length used to smooth unformed surfaces of freshly placed concrete. |
|
Burlap |
A coarse fabric of jute, hemp, or less commonly flax, for use as a
water-retaining cover for curing concrete surfaces; also called Hessian. |
|
Burlap Drag |
Surface texture achieved by trailing moistened coarse burlap from a
device that allows control of the time and rate of texturing. |
|
Butt Joint |
A plain square joint between two concrete slabs. |
|
C |
|
|
Calcareous |
Containing calcium carbonate, or less generally, containing the element
calcium. |
|
Calcium Chloride |
A crystalline solid, CaC12; in various technical grades, used as a
drying agent, as an accelerator of concrete, a deicing chemical, and for
other purposes. |
|
Calcium Lignosulfonate |
An admixture, refined from papermaking wastes, employed in concrete to
retard the set of cement, reduce water requirement and increase strength. |
|
Caliche |
Gravel, sand, or desert debris cement by porous calcium carbonate or
other salts. |
|
California Bearing Ratio |
The ratio of the force per unit area required to penetrate a soil mass
with a 19.4 sq cm circular piston at the rate of 1.27 mm per min to the
force required for corresponding penetration of a standard crushed-rock
base material; the ratio is usually determined at 2.5 mm penetration. |
|
California Profilograph |
Rolling straight edge tool used for evaluating pavement profile (smoothness)
consisting of a 25-ft frame with a sensing wheel located at the center of
the frame that senses and records bumps and dips on graph paper or in a
computer. |
|
Capillary |
In cement paste, any space not occupied by unhydrated cement or cement
gel (air bubbles, whether entrained or entrapped, are not considered to be
part of the cement paste). |
|
Capillary Absorption |
The action of surface tension forces which draws water into capillaries
(i.e., in concrete) without appreciable external pressures. |
|
Capillary Flow |
Flow of moisture through a capillary pore system, such as concrete. |
|
Capillary Space |
In cement paste, any space not occupied by anhydrous cement or cement
gel. (Air bubbles, whether entrained or entrapped, are not considered to
be part of the cement paste.) |
|
Capillary Transmission |
Passage of water or other fluid through capillaries, either by
capillarity or under hydraulic pressure; capillary flow. |
|
Carbide-Milling |
Surface removal or sawing done with carbide milling machine; Machine
uses blade or arbor equipped with carbide-tipped teeth that impact and
chip concrete or asphalt. |
|
Carbonation |
Reaction between carbon dioxide and the products of portland cement
hydration to produce calcium carbonate. |
|
Cast-In-Place |
Concrete placed and finished in its final location. |
|
Cement |
See Portland Cement |
|
Cement Content |
Quantity of cement contained in a unit volume of concrete or mortar,
ordinarily expressed as pounds, barrels, or bags per cubic yard. |
|
Cement Factor |
See Cement Content |
|
Cement Paste |
Constituent of concrete consisting of cement and water. |
|
Cement, Blended |
A hydraulic cement consisting essentially of an intimate and uniform
blend of granulated blast-furnace slag and hydrated lime; or an intimate
and uniform blend of portland cement and granulated blast-furnace slag
cement and pozzolan, produced by intergrinding Portland cement clinker
with the other materials or by blending Portland cement with the other
materials, or a combination of intergrinding and blending. |
|
Cement, Expansive |
A special cement which, when mixed with water, forms a paste that tends
to increase in volume at an early age; used to compensate for volume
decrease due to drying shrinkage. |
|
Cement, High-Early-Strength |
Cement characterized by producing earlier strength in mortar or
concrete than regular cement, referred to in the United States as "Type
III." |
|
Cement, Hydraulic |
Cement that is capable of setting and hardening under water, such as
normal portland cement. |
|
Cement, Normal |
General purpose portland cement, referred to in the United States as
"Type I." |
|
Cement, Portland-Pozzolan |
A hydraulic cement consisting essentially of an intimate and uniform
blend of portland cement or portland blast-furnace slag cement and fine
pozzolan produced by intergrinding portland-cement clinker and pozzolan,
by blending portland cement or portland blast-furnace slag cement and
finely divided pozzolan, or a combination of intergrinding and blending,
in which the pozzolan constituent is within specified limits. |
|
Cement-Aggregate Ratio |
The ratio, by weight or volume, of cement to aggregate. |
|
Cementitious |
Having cementing properties. |
|
Cementitious materials |
Substances that alone have hydraulic cementing properties (set and
harden in the presence of water). Includes: ground granulated blast
furnace slag, natural cement, hydraulic hydrated lime, and combinations of
these and other materials. |
|
Central Mixer |
A stationary concrete mixer from which the fresh concrete is
transported to the work. |
|
Central-Mixed Concrete |
Concrete that is completely mixed in a stationary mixer from which it
is transported to the delivery point. |
|
Chair |
See Bar Support |
|
Chalking |
A phenomenon of coatings, such as cement paint, manifested by the
formation of a loose powder by deterioration of the paint at or just
beneath the surface. |
|
Charging |
Introducing, feeding, or loading materials into a concrete or mortar
mixer, furnace, or other container or receptacle. |
|
Checking |
Development of shallow cracks at closely spaced but irregular intervals
on the surface of mortar or concrete. |
|
Chipping |
Treatment of a hardened concrete surface by chiseling away a portion of
material. |
|
Chute |
A sloping trough or tube for conducting concrete, cement, aggregate, or
other free-flowing materials from a higher to a lower point. |
|
Coarse Aggregate |
See Aggregate, Coarse |
|
Coefficient of Thermal Expansion |
Change in linear dimension per unit length or change in volume per unit
volume per degree of temperature change. |
|
Cohesion Loss |
The loss of internal bond within a joint sealant material; noted by a
noticeable tear along the surface and through the depth of the sealant. |
|
Cohesiveness |
The property of a concrete mix which enables the aggregate particles
and cement paste matrix therein to remain in contact with each other
during mixing, handling, and placing operations; the "stick-togetherness"
of the concrete at a given slump. |
|
Cold Joint |
A discontinuity produced when the concrete surface hardens before the
next batch is placed against it. |
|
Colloidal Mixer |
Grout mixing device that uses a high velocity blade to shear or
separate Cementitious particles in order to break surface tension and
enable complete contact between the particles and mixing water. |
|
Combined Aggregate Grading |
Particle size distribution of a mixture of fine and coarse aggregate. |
|
Compacting Factor |
The ratio obtained by dividing the observed weight of concrete which
fills a container of standard size and shape when allowed to fall into it
under standard conditions of test, by the weight of fully compacted
concrete which fills the same container. |
|
Compaction |
The process whereby the volume of freshly placed mortar or concrete is
reduced to the minimum practical space, usually by vibration,
centrifugation, tamping, or some combination of these; to mold it within
forms or molds and around embedded parts and reinforcement, and to
eliminate voids other than entrained air. See also Consolidation. |
|
Compressible Insert |
Board used to separate a partial-depth patch from an adjacent slab,
usually consisting of a 12-mm thick Styrofoam or compressed fiber material
that is impregnated with asphalt. |
|
Compression Seal |
See Preformed Compression Seal |
|
Compression Test |
Test made on a specimen of mortar or concrete to determine the
compressive strength; in the United States, unless otherwise specified,
compression tests of mortars are made on 50-mm cubes, and compression
tests of concrete are made on cylinders 152 mm in diameter and 305 mm high. |
|
Compressive Strength |
The measured resistance of a concrete or mortar specimen to axial
loading; expressed as pounds per square inch (psi) of cross-sectional
area. |
|
Concrete |
A composite material that consists essentially of a binding medium in
which is embedded particles or fragments of relatively inert material
filler. In portland cement concrete, the binder is a mixture of portland
cement and water; the filler may be any of a wide variety of natural or
artificial aggregates. |
|
Concrete Spreader |
A machine designed to spread concrete from heaps already dumped in
front of it, or to receive and spread concrete in a uniform layer. |
|
Concrete, Normal-weight |
Concrete having a unit weight of approximately 2400 kg/m3 made with
aggregates of normal weight. |
|
Concrete, Reinforced |
Concrete construction that contains mesh or steel bars embedded in it. |
|
Consistency |
The relative mobility or ability of fresh concrete or mortar to flow.
The usual measures of consistency are slump or ball penetration for
concrete and flow for mortar. |
|
Consolidate |
Compaction usually accomplished by vibration of newly placed concrete
to minimum practical volume, to mold it within form shapes or around
embedded parts and reinforcement, and to reduce void content to a
practical minimum. |
|
Consolidation |
The process of inducing a closer arrangement of the solid particles in
freshly mixed concrete or mortar during placement by the reduction of
voids, usually by vibration, centrifugation, tamping, or some combination
of these actions; also applicable to similar manipulation of other
cementitious mixtures, soils, aggregates, or the like. See also Compaction. |
|
Construction Joint |
The junction of two successive placements of concrete, typically with a
keyway or reinforcement across the joint. |
|
Continuously Reinforced Pavement |
A pavement with continuous longitudinal steel reinforcement and no
intermediate transverse expansion or contraction joints. |
|
Contract |
Decrease in length or volume. (See also Expand, Shrinkage, Swelling,
and Volume Change.) |
|
Contraction Joint |
A plane, usually vertical, separating concrete in a structure of
pavement, at a designated location such as to prevent formation of
objectionable shrinkage cracks elsewhere in the concrete. Reinforcing
steel is discontinuous. |
|
Control Joint |
See Contraction Joint |
|
Core |
A cylindrical specimen of standard diameter drilled from a structure or
rock foundation to be bested in compression or examined petrographically. |
|
Corner Break |
A portion of the slab separated by a crack that intersects the adjacent
transverse or longitudinal joints at about a 45º angle with the direction
of traffic. The length of the sides is usually from 0.3 meters to one-half
of the slab width on each side of the crack. |
|
Course |
In concrete construction, a horizontal layer of concrete, usually one
of several making up a lift; in masonry construction, a horizontal layer
of block or brick. See also Lift. |
|
Cover |
In reinforced concrete, the least distance between the surface of the
reinforcement and the outer surface of the concrete. |
|
CPCD |
Concrete pavement contraction design; term used in Texas for jointed
plain concrete pavement (see JPCP). |
|
CPR |
Concrete pavement restoration; the combination of available concrete
repair techniques in one project. |
|
Crack Saw |
Small three-wheeled specialty saw useful for tracing the wandering
nature of a transverse or longitudinal crack; usually contains a pivot
wheel and requires a small diameter crack sawing blade. |
|
Cracking |
The process of contraction or the reflection of stress in the pavement. |
|
Crazing |
Minute surface pattern cracks in mortar or concrete due to unequal
shrinkage or contraction on drying or cooling. |
|
CRC Pavement (CRCP) |
Continuously reinforced concrete pavement; see Continuously Reinforced
Pavement. |
|
Cross Section |
The section of a body perpendicular to a given axis of the body; a
drawing showing such a section. |
|
Crushed Gravel |
The product resulting from the artificial crushing of gravel with a
specified minimum percentage of fragments having one or more faces
resulting from fracture. See also Coarse Aggregate. |
|
Crushed Stone |
The product resulting from the artificial crushing of rocks, boulders,
or large cobblestones, substantially all faces of which possess well-defined
edges and have resulted from the crushing operation. |
|
Crusher-run Aggregate |
Aggregate that has been broken in a mechanical crusher and has not been
subjected to any subsequent screening process. |
|
Cubic Yard |
Normal commercial units of measure of concrete volume, equal to 27
cubic feet. |
|
Cure |
Maintenance of temperature and humidity for freshly placed concrete
during some definite period following placing and finishing to ensure
proper hydration of the cement and proper hardening of the concrete. |
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Curing |
The maintenance of a satisfactory moisture content and temperature in
concrete during its early stages so that desired properties may develop. |
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Curing Blanket |
A built-up covering of sacks, matting, Hessian, straw, waterproof paper,
or other suitable material placed over freshly finished concrete. See also
Burlap. |
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Curing Compound |
A liquid that can be applied as a coating to the surface of newly
placed concrete to retard the loss of water or, in the case of pigmented
compounds, also to reflect heat so as to provide an opportunity for the
concrete to develop its properties in a favorable temperature and moisture
environment. See also Curing. |
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D |
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Damp |
Either moderate absorption or moderate covering of moisture; implies
less wetness than that connoted by "wet," and slightly wetter
than that connoted by "moist." See also Moist and Wet. |
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DBI |
A dowel bar inserter that places the load transfer bars into plastic
concrete as part of the paving operation. |
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Deformed Bar |
A reinforcing bar with a manufactured pattern of surface ridges that
provide a locking anchorage with surrounding concrete. |
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Deformed Reinforcement |
Metal bars, wire, or fabric with a manufactured pattern of surface
ridges that provide a locking anchorage with surrounding concrete. |
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Density |
Mass per unit volume; by common usage in relation to concrete, weight
per unit volume, also referred to as unit weight. |
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Density (dry) |
The mass per unit volume of a dry substance at a stated temperature.
See also Specific Gravity. |
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Density Control |
Control of density of concrete in field construction to ensure that
specified values as determined by standard tests are obtained. |
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Design Strength |
Load capacity of a member computed on the basis of allowable stresses
assumed in design. |
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Deterioration |
1) Physical manifestation of failure (e.g., cracking delamination,
flaking, pitting, scaling, spalling, staining) caused by environmental or
internal autogenous influences on rock and hardened concrete as well as
other materials; 2) decomposition of material during either testing or
exposure to service. See also Disintegration and Weathering. |
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Diamond Grinding |
The process used to remove the upper surface of a concrete pavement to
remove bumps and restore pavement rideability; also, equipment using many
diamond-impregnated saw blades on a shaft or arbor to shave the surface of
concrete slabs. |
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Disincentive |
Deduction in payment resulting from a measured quality lower than
specified for full payment. |
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Dispersing Agent |
Admixtures capable of increasing the fluidity of pastes, mortar or
concretes by reduction of inter-particle attraction. |
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Distress |
Physical manifestation of deterioration and distortion in a concrete
structure as the result of stress, chemical action, and/or physical action. |
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Dolomite |
A mineral having a specific crystal structure and consisting of calcium
carbonate and magnesium carbonate in equivalent chemical amounts (54.27
and 45.73 percent by weight, respectively); a rock containing dolomite as
the principal constituent. |
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Dowel |
1) A steel pin, commonly a plain round steel bar, which extends into
two adjoining portion |