ASTM C125-21a

Standard Terminology Relating to Concrete and Concrete Aggregates

SCOPE
1.1 This standard is a compilation of definitions of terms as they are used in standards under the jurisdiction of Committee C09.  
1.2 Other terminology under the jurisdiction of Committee C09 is included in two specialized standards. Terms relating to constituents of concrete aggregates are defined in Descriptive Nomenclature C294. Terms relating to constituents of aggregates for radiation-shielding concrete are defined in Descriptive Nomenclature C638.  
1.3 Related terminology for hydraulic cement is included in Terminology C219. In the event of conflict between definitions in Terminology C125 and definitions in Terminology C219, definitions in Terminology C125 shall govern for Committee C09 standards.  
1.4 When a term is used in an ASTM standard for which Committee C09 is responsible, it is included herein only if used in more than one Committee C09 standard.
Note 1: The subcommittee responsible for this standard will review definitions on a five-year basis to determine if the definition is still appropriate as stated. Revisions will be made when determined necessary. The year shown in parentheses at the end of a definition indicates the year the definition or revision to the definition was approved. A letter R and a year indicate when the definition was reviewed. No date indicates the term has not yet been reviewed.  
1.5 This terminology includes notes and discussions to definitions that provide supplementary or explanatory information. These notes and discussions shall not be considered as requirements of this standard nor as parts of the definitions.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Sep-2021
• ICS: 91.100.30 - Concrete and concrete products
• Technical Committee: C09 - Concrete and Concrete Aggregates
• Drafting Committee: C09.91 - Terminology

Relations

• Refers: ASTM C94/C94M-24a - Standard Specification for Ready-Mixed Concrete
• Effective Date: 01-Apr-2024
• Refers: ASTM C219-24 - Standard Terminology Relating to Hydraulic and Other Inorganic Cements
• Effective Date: 01-Apr-2024
• Refers: ASTM C670-24a - Standard Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials
• Effective Date: 01-Feb-2024
• Refers: ASTM C1077-24 - Standard Practice for Agencies Testing Concrete and Concrete Aggregates for Use in Construction and Criteria for Testing Agency Evaluation
• Effective Date: 01-Jan-2024
• Refers: ASTM C94/C94M-24 - Standard Specification for Ready-Mixed Concrete
• Effective Date: 01-Jan-2024
• Refers: ASTM C670-24 - Standard Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials
• Effective Date: 01-Jan-2024
• Refers: ASTM C219-20a - Standard Terminology Relating to Hydraulic and Other Inorganic Cements
• Effective Date: 01-Aug-2020
• Refers: ASTM C219-20 - Standard Terminology Relating to Hydraulic and Other Inorganic Cements
• Effective Date: 01-Apr-2020
• Refers: ASTM E135-20 - Standard Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
• Effective Date: 01-Jan-2020
• Refers: ASTM C219-19a - Standard Terminology Relating to Hydraulic and Other Inorganic Cements
• Effective Date: 15-Nov-2019
• Refers: ASTM C94/C94M-19 - Standard Specification for Ready-Mixed Concrete
• Effective Date: 01-Jul-2019
• Refers: ASTM C219-19 - Standard Terminology Relating to Hydraulic Cement
• Effective Date: 01-Jun-2019
• Refers: ASTM E135-19 - Standard Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
• Effective Date: 15-May-2019
• Refers: ASTM C1074-17 - Standard Practice for Estimating Concrete Strength by the Maturity Method
• Effective Date: 15-Dec-2017
• Refers: ASTM C94/C94M-17a - Standard Specification for Ready-Mixed Concrete
• Effective Date: 01-Aug-2017

Overview

ASTM C125-21a: Standard Terminology Relating to Concrete and Concrete Aggregates establishes a comprehensive compilation of definitions for terms commonly used in concrete and concrete aggregate standards administrated by ASTM Committee C09. This international standard ensures consistent communication and understanding across the industry by providing clear and authoritative definitions. Where applicable, the standard references specialized terminology standards for aggregate constituents or hydraulic cements, ensuring coverage of all essential concepts involved in concrete production, testing, specification, and application.

This terminology standard is an essential reference for professionals working with concrete and its components, supporting quality, safety, and compliance in both construction and testing environments.

Key Topics

• Definitions of Core Terms: Provides precise, committee-approved definitions for widely used terms found in ASTM concrete and concrete aggregate standards, such as aggregate, admixture, curing, slump, grading, pozzolan, and more.

• Cross-references to Related Terminology: Terms that are specialized or used infrequently are referenced to other ASTM standards for clarity and comprehensiveness, such as C294 for aggregate constituents, C638 for radiation-shielding aggregates, and C219 for hydraulic cements.

• Supplementary Information: Notes and discussions enhance select definitions for better understanding but are not requirements of the standard.

• Review and Updates: Definitions are reviewed and updated at least every five years to reflect current industry practices and technological advancements in concrete and aggregate sectors.

• Governance Hierarchy: For overlapping terms, C125 definitions prevail in Committee C09 standards to maintain consistency within concrete and aggregate specifications.

Applications

ASTM C125-21a is vital across various phases of the concrete supply chain, including:

• Specification Development: Ensures that architects, engineers, and specifiers use consistent terminology when preparing project documentation and technical requirements involving concrete materials.

• Testing and Quality Control: Laboratories, inspectors, and technicians rely on standardized definitions for test methods, acceptance criteria, and reporting, avoiding ambiguities that could impact compliance or interpretations.

• Construction and Project Management: Helps contractors, construction managers, and site supervisors clearly understand material properties and test results described in job specifications, facilitating effective communication and minimizing disputes.

• Training and Certification: Provides essential terminology for education, certification exams, and professional development for individuals working in the concrete industry.

• International Trade: As an internationally recognized standard, it promotes harmonized language in global construction projects and material supply contracts, supporting compliance with World Trade Organization TBT principles.

Related Standards

Professionals using ASTM C125-21a may also reference these related standards for broader context and technical guidance:

• ASTM C33/C33M - Specification for Concrete Aggregates
• ASTM C94/C94M - Specification for Ready-Mixed Concrete
• ASTM C219 - Terminology Relating to Hydraulic and Other Inorganic Cements
• ASTM C294 - Descriptive Nomenclature for Constituents of Concrete Aggregates
• ASTM C638 - Descriptive Nomenclature of Constituents of Aggregates for Radiation-Shielding Concrete
• ASTM C511 - Specification for Mixing and Curing Rooms Used in Testing
• ASTM C494/C494M - Specification for Chemical Admixtures for Concrete
• ASTM C143/C143M - Test Method for Slump of Hydraulic-Cement Concrete
• ASTM C670 - Practice for Preparing Precision and Bias Statements for Test Methods

For the most current information and updates, always refer to the official ASTM International website and obtain the latest edition of the referenced standards.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: C125 − 21a
Standard Terminology Relating to
Concrete and Concrete Aggregates
This standard is issued under the fixed designation C125; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope* 2. Referenced Documents
1.1 This standard is a compilation of definitions of terms as 2.1 ASTM Standards:
they are used in standards under the jurisdiction of Committee C33/C33M Specification for Concrete Aggregates
C09. C94/C94M Specification for Ready-Mixed Concrete
C143/C143M Test Method for Slump of Hydraulic-Cement
1.2 Other terminology under the jurisdiction of Committee
Concrete
C09 is included in two specialized standards. Terms relating to
C219 Terminology Relating to Hydraulic and Other Inor-
constituents of concrete aggregates are defined in Descriptive
ganic Cements
Nomenclature C294. Terms relating to constituents of aggre-
C294 Descriptive Nomenclature for Constituents of Con-
gates for radiation-shielding concrete are defined in Descrip-
crete Aggregates
tive Nomenclature C638.
C403/C403M Test Method for Time of Setting of Concrete
1.3 Related terminology for hydraulic cement is included in
Mixtures by Penetration Resistance
Terminology C219. In the event of conflict between definitions
C494/C494M Specification for Chemical Admixtures for
in Terminology C125 and definitions in Terminology C219,
Concrete
definitions in Terminology C125 shall govern for Committee
C511 Specification for Mixing Rooms, Moist Cabinets,
C09 standards.
Moist Rooms, and Water Storage Tanks Used in the
1.4 When a term is used in an ASTM standard for which Testing of Hydraulic Cements and Concretes
C638 Descriptive Nomenclature of Constituents of Aggre-
CommitteeC09isresponsible,itisincludedhereinonlyifused
in more than one Committee C09 standard. gates for Radiation-Shielding Concrete
NOTE 1—The subcommittee responsible for this standard will review C670 Practice for Preparing Precision and Bias Statements
definitions on a five-year basis to determine if the definition is still
for Test Methods for Construction Materials
appropriate as stated. Revisions will be made when determined necessary.
C939/C939M Test Method for Flow of Grout for Preplaced-
The year shown in parentheses at the end of a definition indicates the year
Aggregate Concrete (Flow Cone Method)
the definition or revision to the definition was approved. A letter R and a
C1074 Practice for Estimating Concrete Strength by the
year indicate when the definition was reviewed. No date indicates the term
has not yet been reviewed.
Maturity Method
C1077 Practice forAgencies Testing Concrete and Concrete
1.5 This terminology includes notes and discussions to
Aggregates for Use in Construction and Criteria for
definitions that provide supplementary or explanatory informa-
Testing Agency Evaluation
tion. These notes and discussions shall not be considered as
C1240 Specification for Silica Fume Used in Cementitious
requirements of this standard nor as parts of the definitions.
Mixtures
1.6 This international standard was developed in accor-
C1437 Test Method for Flow of Hydraulic Cement Mortar
dance with internationally recognized principles on standard-
C1610/C1610M Test Method for Static Segregation of Self-
ization established in the Decision on Principles for the
Consolidating Concrete Using Column Technique
Development of International Standards, Guides and Recom-
C1611/C1611M Test Method for Slump Flow of Self-
mendations issued by the World Trade Organization Technical
Consolidating Concrete
Barriers to Trade (TBT) Committee.
E135 Terminology Relating to Analytical Chemistry for
Metals, Ores, and Related Materials
This terminology is under the jurisdiction of ASTM Committee C09 on
Concrete and ConcreteAggregates and is the direct responsibility of Subcommittee
C09.91 on Terminology. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Oct. 1, 2021. Published October 2021. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1936. Last previous edition approved in 2021 as C125 – 21. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/C0125-21A. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C125 − 21a
3. Terms and Their Definitions water-reducing admixture, n—admixture that either in-
creases the slump of freshly mixed mortar or concrete without
absorption, n—the process by which a liquid is drawn into and
increasing the water content or that maintains the slump with a
tends to fill permeable pores in a porous solid body; also, the
reduced amount of water due to factors other than air entrain-
increase in mass of a porous solid body resulting from the
ment. (R2008)
penetration of a liquid into its permeable pores. (R2008)
water-reducing admixture, high-range, n—an admixture that
DISCUSSION—In the case of concrete and concrete aggregates, unless
otherwise stated, the liquid involved is water, the increase in mass is reduces the quantity of mixing water required to produce
that which does not include water adhering to the outside surface, the
concrete of a given slump by 12 % or greater. (2021)
increase in mass is expressed as a percentage of the dry mass of the
DISCUSSION—The water reduction of at least 12 % is based on
body and the body is considered to be “dry” when it has been treated
comparingtheperformanceofthetestmixturemadewiththeadmixture
by an appropriate process to remove uncombined water, such as drying
with the performance of the reference mixture in accordance with
to constant mass at a temperature between 100 °C and 110 °C.
Specification C494/C494M.
acceptable range, n—the difference between the largest and
age, equivalent, n—the number of days or hours of curing of
smallest of three or more test determinations that is expected
a concrete mixture at a specified temperature required to
to be exceeded with a probability of about 5 % in the normal
produce a maturity equal to the maturity achieved by a given
and correct operation of the test method. (2019)
curing period at concrete temperatures different from the
DISCUSSION—The acceptable range can be used as an index of
specified temperature. (2015)
precisionfortestmethodsthatdefineatestresultastheaverageofthree
DISCUSSION—The specified temperature is taken typically as the
or more test determinations.
temperature used for standard laboratory curing. For example, a
concrete cured for three days at an elevated temperature may have an
accreditation, n—of testing agency, a process by which an
equivalent age of seven days of curing at the standard laboratory
evaluation authority attests that a testing agency has dem-
temperature.
onstrated the competency to perform specific tasks in accor-
dance with a standard. (2011)
aggregate, n—granular material, such as sand, gravel, crushed
stone, or iron blast-furnace slag, used with a cementing
admixture, n—a material other than water, aggregates, cemen-
medium to form hydraulic-cement concrete or mortar.
titious material, and fiber reinforcement that is used as an
(R2008)
ingredient of a cementitious mixture to modify its freshly
mixed, setting, or hardened properties and that is added to
coarse aggregate, n—(1) aggregate predominantly retained
the batch before or during its mixing. (R2015)
on the 4.75 mm (No. 4) sieve; or (2) that portion of an
aggregate retained on the 4.75 mm (No. 4) sieve. (R2008)
accelerating admixture, n—an admixture that increases the
DISCUSSION—The definitions are alternatives to be applied under
rate of reaction of cementitious materials thus reducing time of
differing circumstances. Definition (1) is applied to an entire aggregate
setting and increasing the rate of early-age strength develop-
eitherinanaturalconditionorafterprocessing.Definition(2)isapplied
ment of a cementitious mixture. (2021)
to a portion of an aggregate. Requirements for properties and grading
air-entraining admixture, n—admixture that causes the de- should be stated in the specification.
velopment of a system of microscopic air bubbles in concrete
fine aggregate, n—(1) aggregate passing the 9.5 mm ( ⁄8 in.)
or mortar during mixing. (R2008)
sieve and almost entirely passing the 4.75 mm (No. 4) sieve
chemical admixture, n—an admixture in the form of a liquid, and predominantly retained on the 75 µm (No. 200) sieve; or
suspension, or water-soluble solid. (2014) (2) that portion of an aggregate passing the 4.75 mm (No. 4)
sieve and retained on the 75 µm (No. 200) sieve. (R2008)
extended set-control admixture, n—an admixture that can
DISCUSSION—The definitions are alternatives to be applied under
predictablyreducethehydrationrateofcementforapplications
differing circumstances. Definition (1) is applied to an entire aggregate
requiring extended time of setting followed by normal strength
eitherinanaturalconditionorafterprocessing.Definition(2)isapplied
development. (2019)
to a portion of an aggregate. Requirements for properties and grading
DISCUSSION—Depending on dosage rate, this admixture can be used
should be stated in the specifications.
to manage the setting time of returned concrete, reduce the hydration of
heavyweight aggregate, n—see high-density aggregate.
cement in wash water from concrete production, permit extended
delivery times of ready mixed concrete, or function as an ordinary
high-density aggregate, n—aggregate with relative density
retarding admixture. Also referred to as a hydration controlling
greater than 3.3, such as: barite, magnetite, limonite, ilmenite,
admixture or a hydration stabilizing admixture.
iron, or steel. (R2008)
mineral admixture, n—deprecated term. (R2008)
lightweight aggregate, n—see low-density aggregate.
DISCUSSION—This term has been used to refer to different types of
water insoluble, finely divided materials such as pozzolanic materials,
low-density aggregate, n—aggregate with bulk density less
cementitious materials, and aggregate. These materials are not similar,
3 3
than 1120 kg/m [70 lb/ft ], such as: pumice, scoria, volcanic
and it is not useful to group them under a single term. The name of the
cinders, tuff, and diatomite; expanded or sintered clay, shale,
specific material should be used, for example, use “pozzolan,” “slag
slate, diatomaceous shale, perlite, vermiculite, or slag; and end
cement,” or “finely divided aggregate,” as is appropriate.
products of coal or coke combustion. (R2008)
retarding admixture, n—an admixture that decreases the rate
of reaction of cementitious materials thus increasing time of normal-density aggregate, n—aggregate that is neither high
setting of a cementitious mixture. (2015) nor low density. (R2008)
C125 − 21a
DISCUSSION—This term refers to aggregate with relative density
bulk density, n—of aggregate, the mass of a unit volume of
typically ranging between 2.4 and 3.0, or with bulk density typically
bulk aggregate material (the unit volume includes the
3 3 3 3
ranging between 1120 kg/m [70 lb/ft ] and 1920 kg/m [120 lb/ft ].
volume of the individual particles and the volume of the
normalweight aggregate, n—see normal-density aggregate.
voids between the particles). (R2008)
DISCUSSION—Thistermreplacesthedeprecatedterm unit weight—of
air content, n—the volume of air voids in cement paste,
aggregate.
mortar, or concrete, exclusive of pore space in aggregate
particles, usually expressed as a percentage of total volume
calcined, adj—heated to a temperature less than the melting
of the paste, mortar, or concrete. (R2008)
point so as to bring about a decomposition, phase transition,
or removal of a volatile fraction of a solid material. (2012)
air-cooled blast-furnace slag—see blast-furnace slag, air-
cooled.
calibration, n—of measuring instrument, a process that, under
specified conditions and following a standard procedure,
air, entrained, n—airvoids,typicallybetween10and1000µm
establishes metrological traceability by determining: (1) the
(1 mm) in diameter and spherical or nearly so, that are
relationship between the quantity values provided by mea-
incorporated intentionally into a cementitious mixture dur-
surement standards or certified reference materials and the
ing mixing by use of an air entraining admixture. (2012)
DISCUSSION—Entrained air is used primarily to increase the durability corresponding indications from a measuring instrument or
of cementitious mixtures exposed to cycles of freezing and thawing in
system; and (2) an estimate of measurement uncertainty of
wet environments. Entrained air may affect workability and strength of
the instrument or system. (2021)
a hardened cementitious mixture.
DISCUSSION—Calibration considers systematic error (or bias) of the
measuring instrument or system as well as random error that is
air, entrapped, n—air voids, typically 1 mm or larger in size
associated with the use of the measurement instrument or system and
and mainly irregular in shape, that are incorporated uninten-
error associated with the measurement standards or certified reference
tionally into a cementitious mixture during mixing and
materials. The estimate of measurement uncertainty of the instrument
handling. (2012)
or system is often expressed as a 95 % confidence interval. Calibration
should not be confused with an adjustment of a measuring instrument
air void—see void, air.
or with verification of a measuring instrument. Sometimes the first step
authority, evaluation, n—an independent entity, apart from
alone is mistakenly called calibration; however, performing only the
the testing agency being evaluated, that has the capability to first step is the process of standardization. In tests of concrete and
concrete aggregates, standardization of measuring instruments or sys-
provide an unbiased evaluation of the technical activities of
tems is often sufficient.
concrete and concrete aggregates testing agencies. (2011)
DISCUSSION—Two acceptable methods of evaluation are inspection
cellular concrete—see concrete, cellular.
and accreditation, and these services are offered by various evaluation
authorities.
cement, hydraulic, n—a cement that sets and hardens by
chemical reaction with water and is capable of doing so
bias, n—the difference between the average value of a property
under water. (R2015)
obtained by a given test method and the accepted reference
or true value of that property. (2019)
cement, slag, n—granulated blast-furnace slag that has been
DISCUSSION—Bias cannot be determined if an accepted reference
ground to cement fineness, with or without additions, and
material is not available or if the property value can be determined only
that is a hydraulic cement. (R2015)
by the given test method.
blast-furnace slag, n—the nonmetallic product, consisting cementitious material (hydraulic), n—an inorganic material
essentially of silicates and aluminosilicates of calcium and or a mixture of inorganic materials that sets and develops
other bases, that is developed in a molten condition simul- strength by chemical reaction with water by formation of
taneously with iron in a blast furnace. (R2008) hydrates and is capable of doing so under water. (R2015)
blast-furnace slag, air-cooled , n—the material resulting from
cementitious material, supplementary, (SCM), n—an inor-
solidification of molten blast-furnace slag under atmospheric
ganic material that contributes to the properties of a cemen-
conditions; subsequent cooling may be accelerated by appli-
titious mixture through hydraulic or pozzolanic activity, or
cation of water to the solidified surface. (R2008)
both. (R2015)
DISCUSSION—Some examples of supplementary cementitious materi-
blast-furnace slag, expanded, n—the low density cellular
als are fly ash, silica fume, slag cement, rice husk ash, natural
material obtained by controlled processing of molten blast-
pozzolans, and ground-glass pozzolans. In practice, these materials are
furnace slag with water or water and other agents, such as
used in combination with portland cement.
steam or compressed air or both. (R2011)
cementitious mixture, n—any mixture containing cementi-
blast-furnace slag, granulated, n—the glassy, granular mate-
tious material and water. (2016)
rialformedwhenmoltenblast-furnaceslagisrapidlychilled,
as by immersion in water. (R2008) DISCUSSION—Paste, grout, mortar, and concrete are examples of
cementitious mixtures.
bleeding, n—the autogenous flow of mixing water within, or
its emergence from, a newly placed cementitious mixture certification, n—of technician, a procedure to determine and
caused by the settlement of the solid materials within the attest in writing that an individual is qualified to perform
mass. (R2013) specific test methods or practices. (R2015)
C125 − 21a
compound, curing, n—a liquid that, when applied to the curing, n—action taken to maintain moisture and temperature
surface of freshly-placed concrete, forms a membrane that conditions in a freshly-placed cementitious mixture to allow
impedes the evaporation of water. (2018) hydraulic cement hydration and (if applicable) pozzolanic
reactions to occur so that the potential properties of the
DISCUSSION—White pigmented curing compounds reflect solar radia-
mixture may develop. (R2015)
tion and reduce surface heating.
curing compound—see compound, curing.
concrete, n—a composite material that consists essentially of a
binding medium within which are embedded particles or
density, n—mass per unit volume of a material (preferred over
fragments of aggregate; in hydraulic-cement concrete, the
term unit weight). (2013)
binder is formed from a mixture of hydraulic cement and
DISCUSSION—For materials with pores that can become filled with
water. (R2015) water, such as aggregate, different modifiers are applied to the term
density depending on which portions of the material are included in
concrete, cellular, n—a low-density cementitious mixture
defining the volume. The modifiers shown on the right are used:
having a homogeneous void or cell structure attained using
Included in the Volume Modifier
gas-forming chemicals or foaming agents. (2016)
Solid portion of material absolute
Solid portion of material plus impermeable pores apparent
concrete, fresh, n—concrete that possesses enough of its
Solid portion of material plus permeable and No modifier is used
impermeable pores
original workability so that it can be placed and consolidated
by the intended methods. (2016) For example, the term apparent density would be the mass of the
solid material divided by the volume of solid material plus imperme-
concrete, hardened, n—concrete that has developed sufficient
able pores.
strength to serve some defined purpose or resist a stipulated
If permeable pores are included in the volume, a delimiting term
loading without failure. (R2015) (or an abbreviation) is used in parentheses to define the moisture
condition of the permeable pores when mass is measured. These de-
concrete, pervious, n—hydraulic-cement concrete propor-
limiting terms are oven-dry (OD) and saturated-surface-dry (SSD).
tioned with sufficient, distributed, interconnected macro-
For example, the term density (SSD) would be the density of a po-
rous material in its SSD condition. The delimiting term is not used
scopic voids that allow water to flow through the material
with absolute density or apparent density, because permeable
under the action of gravity alone. (2015)
pores are not included in the defining volume.
concrete, roller-compacted, RCC, n—concrete compacted
density, relative, n—the ratio of the density of material at a
while fresh by a roller, often a vibratory roller. (R2015)
stated temperature to the density of distilled water at that
concrete, self-consolidating, SCC, n—concrete that can flow
stated temperature; if a temperature is not stated, it is
around reinforcement and consolidate under its own weight
assumed to be 23 °C [73.5 °F]. (2013)
without additional effort and without exceeding specified DISCUSSION—As discussed for the term density, for a porous material
(such as aggregate), different modifiers and delimiting terms are used
limits of segregation. (R2015)
for relative density depending on which density of the material is used
DISCUSSION—Project specifications shall indicate the acceptable seg-
in calculating the ratio. For example, apparent relative density refers
regation based upon a specified test method. Test Method C1610/
to the ratio of apparent density to the density of water and relative
C1610M provides a procedure for determining the degree of aggregate
density (SSD) refers to the ratio of density (SSD) to the density of
segregation under static conditions and the Appendix of Test Method
water.
C1611/C1611M describes a non-mandatory technique for assessing the
degree of segregation under flowing conditions.
difference limit (d2s ord2s%), n—the difference between two
test results that is expected to be exceeded with a probability
consistency, n—of a fresh cementitious mixture, the relative
of about5%inthe normal and correct operation of the test
mobility or ability to flow. (R2015)
DISCUSSION—This characteristic of fresh cementitious mixtures is method; used as an index of precision of the test method.
difficult to quantify and empirical test methods have been adopted to
(2019)
provide indicators of consistency. For example, the slump test de-
DISCUSSION—The difference limit (d2s%) is used if the coefficient of
scribed in Test Method C143/C143M is used for concrete, the flow
variation is used as the statistic to define single-operator and multilabo-
table method described in Test Method C1437 is used for mortar, and
ratory precision. Refer to Practice C670 for additional discussion.
the flow cone method described in Test Method C939/C939M is used
duration, impact, n—the time that the impactor used to
for grout.
generate stress waves is in contact with the test surface; also
consolidation, n—of cementitious mixtures, the process of
referred to as contact time. (2015)
increasing the density of a fresh cementitious mixture in a
elongated piece (of aggregate) , n—a particle of aggregate for
form, mold, or container by reducing the volume of voids.
which the ratio of the length to width of its circumscribing
(R2015)
DISCUSSION—Except for self-consolidating concrete, consolidation rectangular prism is greater than a specified value (see also
is accomplished by inputting mechanical energy, typically by rodding,
flat piece (of aggregate)). (R2015)
tamping, tapping, vibration, or some combination of these actions.
engineer, licensed professional, n—an individual who is
Specific apparatus and methods for consolidation are defined in the
relevant C09 Standards.
licensed to practice engineering as defined by the statutory
requirements of the professional licensing laws of the
crushed gravel—see gravel, crushed.
governing jurisdiction; also referred to as registered profes-
crushed stone—see stone, crushed. sional engineer. (R2015)
C125 − 21a
entrained air—see air, entrapped. gravel, crushed, n—the product resulting from the use of
mechanical devices to break gravel particles into smaller
entrapped air—see air, entrained.
fragments. (R2016)
examiner, n—(1) an individual with the requisite technical
ground-glass pozzolan, n—a supplementary cementitious ma-
qualifications to conduct and score impartially an examina-
terial that results from the processing of suitable recycled
tion of a person’s ability to perform specific test methods or
glass products. (2021)
practices;(2)anindividualdesignatedbyacertificationbody
DISCUSSION—Suitable recycled glass products include container and
to conduct and score certification examinations. (R2015)
plate glass, both made of soda-lime-silica glass, and waste glass-fiber
DISCUSSION—An individual who only supervises a multiple-choice
reinforcement referred to as E-glass.
typeofwrittenexaminationbutdoesnotevaluatethecompetenceofthe
candidates to perform specific procedures is not considered an exam-
grout, n—a cementitious mixture, with or without aggregate or
iner.Theexaminerrequiresrequisitetechnicalqualificationstoexercise
admixtures, that is used primarily to fill voids. (2021)
judgment in scoring a candidate’s ability to perform a specific proce-
dure.
grout (nonshrink), hydraulic-cement, n—a grout containing
hydraulic-cement that, under unrestrained conditions, has a
factor, temperature-time, n—the maturity index computed as
hardened volume greater than or equal to the original
the area between the concrete temperature and the datum
installed volume. (2018)
temperature from the plot of measured concrete temperature
DISCUSSION—This type of grout is often used as a transfer medium
versus time, expressed in units of degree-days or degree-
between load-bearing members. Unrestrained conditions means the
hours. (2015)
grout is free to expand during hardening.
fibers, n—slender filaments, which may be discrete or in the
hardened concrete—see concrete, hardened.
form of bundles, networks, or strands of natural or manu-
hardening, n—gain of strength and other properties of a
factured materials that can be distributed uniformly through-
out a fresh cementitious mixture. (2018) cementitious mixture after final setting. (2018)
fineness modulus, n—of aggregate, a factor obtained by hydraulic cement—see cement, hydraulic.
adding the percentages of material in the sample that is
identical test specimens, n—test specimens selected at ran-
coarser than each of the following sieves (cumulative
dom that were made from a single quantity or batch of
percentages retained), and dividing the sum by 100: 150 µm
materials, which is as homogeneous as possible,
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C125 − 21 C125 − 21a
Standard Terminology Relating to
Concrete and Concrete Aggregates
This standard is issued under the fixed designation C125; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This standard is a compilation of definitions of terms as they are used in standards under the jurisdiction of Committee C09.
1.2 Other terminology under the jurisdiction of Committee C09 is included in two specialized standards. Terms relating to
constituents of concrete aggregates are defined in Descriptive Nomenclature C294. Terms relating to constituents of aggregates for
radiation-shielding concrete are defined in Descriptive Nomenclature C638.
1.3 Related terminology for hydraulic cement is included in Terminology C219. In the event of conflict between definitions in
Terminology C125 and definitions in Terminology C219, definitions in Terminology C125 shall govern for Committee C09
standards.
1.4 When a term is used in an ASTM standard for which Committee C09 is responsible, it is included herein only if used in more
than one Committee C09 standard.
NOTE 1—The subcommittee responsible for this standard will review definitions on a five-year basis to determine if the definition is still appropriate as
stated. Revisions will be made when determined necessary. The year shown in parentheses at the end of a definition indicates the year the definition or
revision to the definition was approved. A letter R and a year indicate when the definition was reviewed. No date indicates the term has not yet been
reviewed.
1.5 This terminology includes notes and discussions to definitions that provide supplementary or explanatory information. These
notes and discussions shall not be considered as requirements of this standard nor as parts of the definitions.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
C33/C33M Specification for Concrete Aggregates
C94/C94M Specification for Ready-Mixed Concrete
This terminology is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.91 on
Terminology.
Current edition approved July 1, 2021Oct. 1, 2021. Published August 2021October 2021. Originally approved in 1936. Last previous edition approved in 20202021 as
C125 – 20.C125 – 21. DOI: 10.1520/C0125-21.10.1520/C0125-21A.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C125 − 21a
C143/C143M Test Method for Slump of Hydraulic-Cement Concrete
C219 Terminology Relating to Hydraulic and Other Inorganic Cements
C294 Descriptive Nomenclature for Constituents of Concrete Aggregates
C403/C403M Test Method for Time of Setting of Concrete Mixtures by Penetration Resistance
C494/C494M Specification for Chemical Admixtures for Concrete
C511 Specification for Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic
Cements and Concretes
C638 Descriptive Nomenclature of Constituents of Aggregates for Radiation-Shielding Concrete
C670 Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials
C939/C939M Test Method for Flow of Grout for Preplaced-Aggregate Concrete (Flow Cone Method)
C1074 Practice for Estimating Concrete Strength by the Maturity Method
C1077 Practice for Agencies Testing Concrete and Concrete Aggregates for Use in Construction and Criteria for Testing Agency
Evaluation
C1240 Specification for Silica Fume Used in Cementitious Mixtures
C1437 Test Method for Flow of Hydraulic Cement Mortar
C1610/C1610M Test Method for Static Segregation of Self-Consolidating Concrete Using Column Technique
C1611/C1611M Test Method for Slump Flow of Self-Consolidating Concrete
E135 Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
3. Terms and Their Definitions
absorption, n—the process by which a liquid is drawn into and tends to fill permeable pores in a porous solid body; also, the
increase in mass of a porous solid body resulting from the penetration of a liquid into its permeable pores. (R2008)
DISCUSSION—
In the case of concrete and concrete aggregates, unless otherwise stated, the liquid involved is water, the increase in mass is that which does not include
water adhering to the outside surface, the increase in mass is expressed as a percentage of the dry mass of the body and the body is considered to be
“dry” when it has been treated by an appropriate process to remove uncombined water, such as drying to constant mass at a temperature between 100 °C
and 110 °C.
acceptable range, n—the difference between the largest and smallest of three or more test determinations that is expected to
be exceeded with a probability of about 5 % in the normal and correct operation of the test method. (2019)
DISCUSSION—
The acceptable range can be used as an index of precision for test methods that define a test result as the average of three or more test determinations.
accreditation, n—of testing agency, a process by which an evaluation authority attests that a testing agency has demonstrated
the competency to perform specific tasks in accordance with a standard. (2011)
admixture, n—a material other than water, aggregates, cementitious material, and fiber reinforcement that is used as an
ingredient of a cementitious mixture to modify its freshly mixed, setting, or hardened properties and that is added to the batch
before or during its mixing. (R2015)
accelerating admixture,n—an admixture that increases the rate of reaction of cementitious materials thus reducing time of setting
and increasing the rate of early-age strength development of a cementitious mixture. (2021)
air-entraining admixture,n—admixture that causes the development of a system of microscopic air bubbles in concrete or mortar
during mixing. (R2008)
chemical admixture,n—an admixture in the form of a liquid, suspension, or water-soluble solid. (2014)
extended set-control admixture, n—an admixture that can predictably reduce the hydration rate of cement for applications
requiring extended time of setting followed by normal strength development. (2019)
DISCUSSION—
Depending on dosage rate, this admixture can be used to manage the setting time of returned concrete, reduce the hydration of cement in wash water
from concrete production, permit extended delivery times of ready mixed concrete, or function as an ordinary retarding admixture. Also referred to
as a hydration controlling admixture or a hydration stabilizing admixture.
mineral admixture,n—deprecated term. (R2008)
DISCUSSION—
This term has been used to refer to different types of water insoluble, finely divided materials such as pozzolanic materials, cementitious materials,
and aggregate. These materials are not similar, and it is not useful to group them under a single term. The name of the specific material should be used,
for example, use “pozzolan,” “slag cement,” or “finely divided aggregate,” as is appropriate.
C125 − 21a
retarding admixture,n—an admixture that decreases the rate of reaction of cementitious materials thus increasing time of setting
of a cementitious mixture. (2015)
water-reducing admixture,n—admixture that either increases the slump of freshly mixed mortar or concrete without increasing
the water content or that maintains the slump with a reduced amount of water due to factors other than air entrainment. (R2008)
water-reducing admixture, high-range,n—an admixture that reduces the quantity of mixing water required to produce concrete
of a given slump by 12 % or greater. (2021)
DISCUSSION—
The water reduction of at least 12 % is based on comparing the performance of the test mixture made with the admixture with the performance of the
reference mixture in accordance with Specification C494/C494M.
age, equivalent, n—the number of days or hours of curing of a concrete mixture at a specified temperature required to produce
a maturity equal to the maturity achieved by a given curing period at concrete temperatures different from the specified
temperature. (2015)
DISCUSSION—
The specified temperature is taken typically as the temperature used for standard laboratory curing. For example, a concrete cured for three days at
an elevated temperature may have an equivalent age of seven days of curing at the standard laboratory temperature.
aggregate, n—granular material, such as sand, gravel, crushed stone, or iron blast-furnace slag, used with a cementing medium
to form hydraulic-cement concrete or mortar. (R2008)
coarse aggregate,n—(1) aggregate predominantly retained on the 4.75 mm (No. 4) sieve; or (2) that portion of an aggregate
retained on the 4.75 mm (No. 4) sieve. (R2008)
DISCUSSION—
The definitions are alternatives to be applied under differing circumstances. Definition (1) is applied to an entire aggregate either in a natural condition
or after processing. Definition (2) is applied to a portion of an aggregate. Requirements for properties and grading should be stated in the specification.
fine aggregate,n—(1) aggregate passing the 9.5 mm ( ⁄8 in.) sieve and almost entirely passing the 4.75 mm (No. 4) sieve and
predominantly retained on the 75 μm (No. 200) sieve; or (2) that portion of an aggregate passing the 4.75 mm (No. 4) sieve and
retained on the 75 μm (No. 200) sieve. (R2008)
DISCUSSION—
The definitions are alternatives to be applied under differing circumstances. Definition (1) is applied to an entire aggregate either in a natural condition
or after processing. Definition (2) is applied to a portion of an aggregate. Requirements for properties and grading should be stated in the specifications.
heavyweight aggregate,n—see high-density aggregate.
high-density aggregate,n—aggregate with relative density greater than 3.3, such as: barite, magnetite, limonite, ilmenite, iron,
or steel. (R2008)
lightweight aggregate,n—see low-density aggregate.
3 3
low-density aggregate,n—aggregate with bulk density less than 1120 kg/m [70 lb/ft ], such as: pumice, scoria, volcanic cinders,
tuff, and diatomite; expanded or sintered clay, shale, slate, diatomaceous shale, perlite, vermiculite, or slag; and end products of
coal or coke combustion. (R2008)
normal-density aggregate,n—aggregate that is neither high nor low density. (R2008)
DISCUSSION—
This term refers to aggregate with relative density typically ranging between 2.4 and 3.0, or with bulk density typically ranging between 1120 kg/m
3 3 3
[70 lb/ft ] and 1920 kg/m [120 lb/ft ].
normalweight aggregate,n—see normal-density aggregate.
air content, n—the volume of air voids in cement paste, mortar, or concrete, exclusive of pore space in aggregate particles,
usually expressed as a percentage of total volume of the paste, mortar, or concrete. (R2008)
air-cooled blast-furnace slag—see blast-furnace slag, air-cooled.
air, entrained, n—air voids, typically between 10 and 1000 μm (1 mm) in diameter and spherical or nearly so, that are
incorporated intentionally into a cementitious mixture during mixing by use of an air entraining admixture. (2012)
DISCUSSION—
Entrained air is used primarily to increase the durability of cementitious mixtures exposed to cycles of freezing and thawing in wet environments.
Entrained air may affect workability and strength of a hardened cementitious mixture.
C125 − 21a
air, entrapped, n—air voids, typically 1 mm or larger in size and mainly irregular in shape, that are incorporated unintentionally
into a cementitious mixture during mixing and handling. (2012)
air void—see void, air.
authority, evaluation, n—an independent entity, apart from the testing agency being evaluated, that has the capability to provide
an unbiased evaluation of the technical activities of concrete and concrete aggregates testing agencies. (2011)
DISCUSSION—
Two acceptable methods of evaluation are inspection and accreditation, and these services are offered by various evaluation authorities.
bias, n—the difference between the average value of a property obtained by a given test method and the accepted reference or
true value of that property. (2019)
DISCUSSION—
Bias cannot be determined if an accepted reference material is not available or if the property value can be determined only by the given test method.
blast-furnace slag, n—the nonmetallic product, consisting essentially of silicates and aluminosilicates of calcium and other
bases, that is developed in a molten condition simultaneously with iron in a blast furnace. (R2008)
blast-furnace slag, air-cooled , n—the material resulting from solidification of molten blast-furnace slag under atmospheric
conditions; subsequent cooling may be accelerated by application of water to the solidified surface. (R2008)
blast-furnace slag, expanded, n—the low density cellular material obtained by controlled processing of molten blast-furnace
slag with water or water and other agents, such as steam or compressed air or both. (R2011)
blast-furnace slag, granulated, n—the glassy, granular material formed when molten blast-furnace slag is rapidly chilled, as
by immersion in water. (R2008)
bleeding, n—the autogenous flow of mixing water within, or its emergence from, a newly placed cementitious mixture caused
by the settlement of the solid materials within the mass. (R2013)
bulk density, n—of aggregate, the mass of a unit volume of bulk aggregate material (the unit volume includes the volume of
the individual particles and the volume of the voids between the particles). (R2008)
DISCUSSION—
This term replaces the deprecated term unit weight—of aggregate.
calcined, adj—heated to a temperature less than the melting point so as to bring about a decomposition, phase transition, or
removal of a volatile fraction of a solid material. (2012)
calibration, n—of measuring instrument, a process that, under specified conditions and following a standard procedure,
establishes metrological traceability by determining: (1) the relationship between the quantity values provided by measurement
standards or certified reference materials and the corresponding indications from a measuring instrument or system; and (2) an
estimate of measurement uncertainty of the instrument or system. (2021)
DISCUSSION—
Calibration considers systematic error (or bias) of the measuring instrument or system as well as random error that is associated with the use of the
measurement instrument or system and error associated with the measurement standards or certified reference materials. The estimate of measurement
uncertainty of the instrument or system is often expressed as a 95 % confidence interval. Calibration should not be confused with an adjustment of
a measuring instrument or with verification of a measuring instrument. Sometimes the first step alone is mistakenly called calibration; however,
performing only the first step is the process of standardization. In tests of concrete and concrete aggregates, standardization of measuring instruments
or systems is often sufficient.
cellular concrete—see concrete, cellular.
C125 − 21a
cement, hydraulic, n—a cement that sets and hardens by chemical reaction with water and is capable of doing so under water.
(R2015)
cement, slag, n—granulated blast-furnace slag that has been ground to cement fineness, with or without additions, and that is
a hydraulic cement. (R2015)
cementitious material (hydraulic),n—an inorganic material or a mixture of inorganic materials that sets and develops strength
by chemical reaction with water by formation of hydrates and is capable of doing so under water. (R2015)
cementitious material, supplementary, (SCM), n—an inorganic material that contributes to the properties of a cementitious
mixture through hydraulic or pozzolanic activity, or both. (R2015)
DISCUSSION—
Some examples of supplementary cementitious materials are fly ash, silica fume, slag cement, rice husk ash, natural pozzolans, and ground-glass
pozzolans. In practice, these materials are used in combination with portland cement.
cementitious mixture, n—any mixture containing cementitious material and water. (2016)
DISCUSSION—
Paste, grout, mortar, and concrete are examples of cementitious mixtures.
certification, n—of technician, a procedure to determine and attest in writing that an individual is qualified to perform specific
test methods or practices. (R2015)
compound, curing, n—a liquid that, when applied to the surface of freshly-placed concrete, forms a membrane that impedes
the evaporation of water. (2018)
DISCUSSION—
White pigmented curing compounds reflect solar radiation and reduce surface heating.
concrete, n—a composite material that consists essentially of a binding medium within which are embedded particles or
fragments of aggregate; in hydraulic-cement concrete, the binder is formed from a mixture of hydraulic cement and water.
(R2015)
concrete, cellular, n—a low-density cementitious mixture having a homogeneous void or cell structure attained using
gas-forming chemicals or foaming agents. (2016)
concrete, fresh, n—concrete that possesses enough of its original workability so that it can be placed and consolidated by the
intended methods. (2016)
concrete, hardened, n—concrete that has developed sufficient strength to serve some defined purpose or resist a stipulated
loading without failure. (R2015)
concrete, pervious, n—hydraulic-cement concrete proportioned with sufficient, distributed, interconnected macroscopic voids
that allow water to flow through the material under the action of gravity alone. (2015)
concrete, roller-compacted, RCC, n—concrete compacted while fresh by a roller, often a vibratory roller. (R2015)
concrete, self-consolidating, SCC, n—concrete that can flow around reinforcement and consolidate under its own weight
without additional effort and without exceeding specified limits of segregation. (R2015)
DISCUSSION—
Project specifications shall indicate the acceptable segregation based upon a specified test method. Test Method C1610/C1610M provides a procedure
C125 − 21a
for determining the degree of aggregate segregation under static conditions and the Appendix of Test Method C1611/C1611M describes a
non-mandatory technique for assessing the degree of segregation under flowing conditions.
consistency, n—of a fresh cementitious mixture, the relative mobility or ability to flow. (R2015)
DISCUSSION—
This characteristic of fresh cementitious mixtures is difficult to quantify and empirical test methods have been adopted to provide indicators of
consistency. For example, the slump test described in Test Method C143/C143M is used for concrete, the flow table method described in Test Method
C1437 is used for mortar, and the flow cone method described in Test Method C939/C939M is used for grout.
consolidation, n—of cementitious mixtures, the process of increasing the density of a fresh cementitious mixture in a form, mold,
or container by reducing the volume of voids. (R2015)
DISCUSSION—
Except for self-consolidating concrete, consolidation is accomplished by inputting mechanical energy, typically by rodding, tamping, tapping,
vibration, or some combination of these actions. Specific apparatus and methods for consolidation are defined in the relevant C09 Standards.
crushed gravel—see gravel, crushed.
crushed stone—see stone, crushed.
curing, n—action taken to maintain moisture and temperature conditions in a freshly-placed cementitious mixture to allow
hydraulic cement hydration and (if applicable) pozzolanic reactions to occur so that the potential properties of the mixture may
develop. (R2015)
curing compound—see compound, curing.
density, n—mass per unit volume of a material (preferred over term unit weight). (2013)
DISCUSSION—
For materials with pores that can become filled with water, such as aggregate, different modifiers are applied to the term density depending on which
portions of the material are included in defining the volume. The modifiers shown on the right are used:
Included in the Volume Modifier
Solid portion of material absolute
Solid portion of material plus impermeable pores apparent
Solid portion of material plus permeable and impermeable pores No modifier is used
For example, the term apparent density would be the mass of the solid material divided by the volume of solid material plus impermeable pores.
If permeable pores are included in the volume, a delimiting term (or an abbreviation) is used in parentheses to define the moisture condition of
the permeable pores when mass is measured. These delimiting terms are oven-dry (OD) and saturated-surface-dry (SSD). For example, the term
density (SSD) would be the density of a porous material in its SSD condition. The delimiting term is not used with absolute density or apparent
density, because permeable pores are not included in the defining volume.
density, relative, n—the ratio of the density of material at a stated temperature to the density of distilled water at that stated
temperature; if a temperature is not stated, it is assumed to be 23 °C [73.5 °F]. (2013)
DISCUSSION—
As discussed for the term density, for a porous material (such as aggregate), different modifiers and delimiting terms are used for relative density
depending on which density of the material is used in calculating the ratio. For example, apparent relative density refers to the ratio of apparent
density to the density of water and relative density (SSD) refers to the ratio of density (SSD) to the density of water.
difference limit (d2s or d2s%), n—the difference between two test results that is expected to be exceeded with a probability of
about 5 % in the normal and correct operation of the test method; used as an index of precision of the test method. (2019)
DISCUSSION—
The difference limit (d2s%) is used if the coefficient of variation is used as the statistic to define single-operator and multilaboratory precision. Refer
to Practice C670 for additional discussion.
C125 − 21a
duration, impact, n—the time that the impactor used to generate stress waves is in contact with the test surface; also referred
to as contact time. (2015)
elongated piece (of aggregate) , n—a particle of aggregate for which the ratio of the length to width of its circumscribing
rectangular prism is greater than a specified value (see also flat piece (of aggregate)). (R2015)
engineer, licensed professional, n—an individual who is licensed to practice engineering as defined by the statutory
requirements of the professional licensing laws of the governing jurisdiction; also referred to as registered professional engineer.
(R2015)
entrained air—see air, entrapped.
entrapped air—see air, entrained.
examiner, n—(1) an individual with the requisite technical qualifications to conduct and score impartially an examination of a
person’s ability to perform specific test methods or practices; (2) an individual designated by a certification body to conduct and
score certification examinations. (R2015)
DISCUSSION—
An individual who only supervises a multiple-choice type of written examination but does not evaluate the competence of the candidates to perform
specific procedures is not considered an examiner. The examiner requires requisite technical qualifications to exercise judgment in scoring a candidate’s
ability to perform a specific procedure.
factor, temperature-time, n—the maturity index computed as the area between the concrete temperature and the datum
temperature from the plot of measured concrete temperature versus time, expressed in units of degree-days or degree-hours.
(2015)
fibers, n—slender filaments, which may be discrete or in the form of bundles, networks, or strands of natural or manufactured
materials that can be distributed uniformly throughout a fresh cementitious mixture. (2018)
fineness modulus, n—of aggregate, a factor obtained by adding the percentages of material in the sample that is coarser than
each of the following sieves (cumulative percentages retained), and dividing the sum by 100: 150 μm (No. 100), 300 μm (No.
3 3
50), 600 μm (No. 30), 1.18 mm (No. 16), 2.36 mm (No. 8), 4.75 mm (No. 4), 9.5 mm ( ⁄8 in.), 19.0 mm ( ⁄4 in.), 37.5 mm
(1 ⁄2 in.), 75 mm (3 in.), 150 mm (6 in.). (R2016)
flat piece (of aggregate),n—a particle of aggregate for which the ratio of the width to thickness of its circumscribing rectangular
prism is greater than a specified value (see also elongated piece (of aggregate)). (R2016)
fly ash, n—finely divided residue that results from the process of combustion of ground or powdered coal and that is transported
by flue gases. (R2016)
DISCUSSION—
This definition of fly ash does not include, among other things, the residue resulting from: (1) fluidized bed combustion, (2) the burning of municipal
solid waste or any other refuse with coal, or (3) the burning of industrial or municipal solid waste in incinerators.
fog room, n—a moist room in which the humidity is controlled by atomization of water. (see moist room) (R2016)
frequency, sampling, n—as applied to digital data acquisition instruments, the rate at which the points that comprise the
waveform are recorded; the inverse of the sampling interval, expressed in Hz or samples/s; also referred to as sampling rate.
(R2016)
fresh concrete—see concrete, fresh.
C125 − 21a
granula
...