ASTM C638-92(2002)

Standard Descriptive Nonmenclature of Constituents of Aggregates for Radiation-Shielding Concrete

SCOPE
1.1 This nomenclature is intended to give accurate descriptions of some common or important naturally occurring and synthetic constituents of aggregates for radiation-shielding concrete, that, at the same time, are not common or important constituents of concrete aggregates in general use. While most of the minerals and rocks discussed below may occur in small quantities in aggregates in general use, they are not major constituents of such aggregates. Common constituents of aggregates in general use are described in Descriptive Nomenclature C 294. Radiation-shielding concrete often contains such aggregates, but other special aggregates are used in some circumstances.
1.2 The synthetic aggregates included are ferrophosphorus and boron frit.
1.3 The descriptions are not adequate to permit the identification of materials, since accurate identification of natural and synthetic aggregate constituents in many cases can only be made by a qualified geologist, mineralogist, or petrographer, using the apparatus and procedures of those sciences.

General Information

• Status: Historical
• Publication Date: 09-Dec-2002
• ICS: 13.280 - Radiation protection
• ICS: 91.100.30 - Concrete and concrete products
• Technical Committee: C09 - Concrete and Concrete Aggregates
• Drafting Committee: C09.41 - Hydraulic Cement Grouts

Relations

• Replaces: ASTM C638-92(1997) - Standard Descriptive Nonmenclature of Constituents of Aggregates for Radiation-Shielding Concrete
• Effective Date: 10-Dec-2002
• Replaced By: ASTM C638-09 - Standard Descriptive Nonmenclature of Constituents of Aggregates for Radiation-Shielding Concrete
• Effective Date: 01-Dec-2009
• Referred By: ASTM C637-20 - Standard Specification for Aggregates for Radiation-Shielding Concrete
• Effective Date: 10-Dec-2002
• Referred By: ASTM C125-21a - Standard Terminology Relating to Concrete and Concrete Aggregates
• Effective Date: 10-Dec-2002
• Referred By: ASTM C33/C33M-23 - Standard Specification for Concrete Aggregates
• Effective Date: 10-Dec-2002

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information.
Designation:C638–92 (Reapproved 2002)
Standard Descriptive Nomenclature of
Constituents of Aggregates for Radiation-Shielding
Concrete
This standard is issued under the fixed designation C638; 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 Department of Defense.
1. Scope minerals and synthetic glasses of substantial boron content that
are particularly effective in absorbing thermal neutrons without
1.1 This nomenclature is intended to give accurate descrip-
producing highly penetrating gamma rays. The boron-frit
tions of some common or important naturally occurring and
glasses are included because of their frequent use.
synthetic constituents of aggregates for radiation-shielding
concrete, that, at the same time, are not common or important
HEAVYAGGREGATES
constituents of concrete aggregates in general use. While most
of the minerals and rocks discussed below may occur in small
4. Descriptions of Naturally Occurring Constituents
quantities in aggregates in general use, they are not major
4.1 Members of this group have higher specific gravities
constituents of such aggregates. Common constituents of
than aggregates in general use. Six are iron minerals, of which
aggregates in general use are described in Descriptive Nomen-
five are important iron ore minerals and the sixth is an ore of
clature C294. Radiation-shielding concrete often contains such
titanium. Two are barium minerals worked as the principal
aggregates, but other special aggregates are used in some
sources of barium salts. The other is ferrophosphorus, a
circumstances.
mixture of synthetic iron phosphides.
1.2 The synthetic aggregates included are ferrophosphorus
4.2 The constituents are described below first as minerals,
and boron frit.
and then as major constituents of ores when their aspect as
1.3 The descriptions are not adequate to permit the identi-
major constituents of ores affects the behavior of ores as
fication of materials, since accurate identification of natural
concrete aggregates.
and synthetic aggregate constituents in many cases can only be
made by a qualified geologist, mineralogist, or petrographer,
5. Iron Minerals and Ores
using the apparatus and procedures of those sciences.
5.1 Hematite (Fe O )—Hematite has a hardness of 5 to 6 on
2 3
Mohs’ scale (will be scratched by hard steel), and a specific
2. Referenced Documents
gravity of 5.26 when pure. The color varies from bright red to
2.1 ASTM Standards:
dull red to steel gray; luster varies from metallic to submetallic
C294 Descriptive Nomenclature for Constituents of Con-
to dull; the streak is cherry red or reddish brown; it is
crete Aggregates
nonmagnetic.
5.1.1 Hematite Ores—Rocks of which hematite is the major
3. Types of Materials
constituent vary from one deposit to another, and within the
3.1 Two classes of materials are described below. The first
deposit, in specific gravity, toughness, compactness, amount of
class consists of minerals and rocks formed from them, and
impurities, degree of weathering, and suitability for use as
synthetic materials, that have high specific gravity and in
concreteaggregate.Hematiteappearstobetheironoremineral
addition contain substantial proportions of atoms of high or
most exploited as a source of iron. The ores of the Lake
moderately high atomic weight. They are referred to as heavy
Superior region are banded sedimentary ores consisting of
or high-density aggregates. The second class consists of
layers rich in hematite, and sometimes goethite, iron silicates,
such as stilpnomelane, minnesotaite, greenalite, grunerite, and
iron carbonate, alternating with silica-rich layers of chert or
This nomenclature is under the jurisdiction of ASTM Committee C09 on
Concrete and ConcreteAggregates and is the direct responsibility of Subcommittee
fine-grained quartz or a mixture. The Birmingham,ALores are
C09.41 on Pre-placed Aggregate Concrete for Radiation Shielding.
oolitic with hematite replacements of oölites and fossils in a
Current edition approved Dec. 10, 2002. Published February 2003. Originally
matrix that ranges from fine-grained earthy hematite, with or
approved in 1973. Last previous edition approved in 1992 as C638 – 92. DOI:
10.1520/C0638-92R02.
Annual Book of ASTM Standards, Vol 04.02.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
C638–92 (2002)
without calcite, to crystalline calcite. Hematite ores dust in 5.6.1 Magnetite Ores—These ores can form dense, tough,
handling, with the dust ranging in color from moderate red to usually coarse-grained rocks with few impurities. Magnetite
dusky red to moderate reddish brown (5R 4/6 to 5R 3/4 to 10R ores are associated with metamorphic or igneous or sedimen-
4/6). tary rocks, and therefore, the impurities associated with mag-
5.2 Ilmenite (FeTiO with minor Mg and Mn)—Ilmenite has netite ores may include a wide variety of rock-forming and
a hardness of 5 to 6 and specific gravity of 4.72 6 0.04 when accessory minerals. Magnetite occurs in association with
pure.Thecolorisironblackwithmetallictosubmetallicluster; hematite and ilmenite; magnetic ores are widely distributed,
the streak is black; it is feebly magnetic. but many are not suitable for use as heavy aggregate because
5.2.1 Ilmenite Ores—These ores consist of crystalline il- the magnetite occurs disseminated through rock rather than as
menite with either magnetite or hematite and constituents of a major rock-forming mineral. One of the most widely used
the associated gabbroic or anorthositic rocks. Massive ilmenite types of heavy aggregates is magnetite ore.
ores can form coarsely crystalline massive tough rocks but
vary, from deposit to deposit, and within a deposit, in specific 6. Barium Minerals
gravity, composition, hardness, and suitability for use as 1
6.1 Witherite (BaCO )—Witheritehasahardnessof3to3 ⁄2
concrete aggregate. Many ilmenite ores consist of ilmenite
andaspecificgravityof4.29whenpure.Thecolorrangesfrom
disseminated in rock rather than concentrated as a major
colorless to white to grayish or many pale colors. Like calcite
rock-forming mineral. Ilmenite concentrated from beach sands
and aragonite, witherite is decomposed with effervescence by
is usually altered to a variable degree, and its mechanical
dilute hydrochloric acid (HCl). Witherite, the second most
properties probably differ from those of unaltered ilmenite.
common barium mineral, occurs with barite and galena.
One of the most widely used types of heavy aggregates is
England is the chief producer of witherite, and barium-
ilmenite ore.
containing heavy aggregates in Great Britain might be ex-
5.3 Lepidocrocite (FeO(OH))—Lepidocrocite has a hard-
pected to contain witherite as a major constituent.
ness of 5 and specific gravity of 4.09 when pure. The color
6.2 Barite (BaSO ) (also, but improperly, called barytes)—
varies from ruby red to reddish brown and the streak is dull
Barite has a hardness of 3 to 3 ⁄2 and a specific gravity of 4.50
orange. Lepidocrocite and goethite occur together, and lepi-
when pure. The color ranges from colorless to white to many
docrocite may be a constituent of goethite and limonite ores.
usually pale colors.
5.4 Goethite (HFeO )—Goethite has the same chemical
6.2.1 Barite is the most common barium mineral and the
composition as lepidocrocite but crystallizes differently. The
major barium ore. It occurs in veins transecting many kinds of
hardness is 5 to 5 ⁄2 and the specific gravity is 4.28 6 0.01
rocks, concentrated in sedimentary rocks, and as residual
when pure and 3.3 to 4.3 in massive goethite. The color varies
nodules in clays formed by the solution of sedimentary rocks.
with the form, from crystals that are blackish brown with
In many of its occurrences it is accompanied by clay or a
imperfect adamantine-metallic luster, to dull or silky luster in
calcium sulfate mineral (gypsum or anhydrite) or both. Al-
fibrous varieties; massive goethite is yellowish brown to
though barite from residual deposits is often weathered, it is
reddish brown; clayey material is brownish yellow to ocher
possible to obtain clean, well-graded barite aggregate.
yellow. The streak is brownish yellow to ocher yellow.
5.4.1 Goethite Ores—These ores range from hard tough
7. Ferrophosphorus
massive rocks to soft crumbling earths; these alterations
7.1 Ferrophosphorus, a material produced in the production
frequently occur within fractions of an inch.
of phosphorus, consists of a mixture of iron phosphides, and
5.5 Limonite—A general name for hydrous iron oxides of
has been used as coarse and fine
...