Standard Test Method for Creep of Concrete in Compression

SIGNIFICANCE AND USE
This test method measures the load-induced time-dependent compressive strain at selected ages for concrete under an arbitrary set of controlled environmental conditions.
This test method can be used to compare creep potentials of different concretes. A procedure is available, using the developed equation (or graphical plot), for calculating stress from strain data within massive non-reinforced concrete structures. For most specific design applications, the test conditions set forth herein must be modified to more closely simulate the anticipated curing, thermal, exposure, and loading age conditions for the prototype structure. Current theories and effects of material and environmental parameters are presented in ACI SP-9, Symposium on Creep of Concrete.3  
In the absence of a satisfactory hypothesis governing creep phenomena, a number of assumptions have been developed that have been generally substantiated by test and experience.
3.3.1 Creep is proportional to stress from 0 to 40 % of concrete compressive strength.
3.3.2 Creep has been conclusively shown to be directly proportional to paste content throughout the range of paste contents normally used in concrete. Thus, the creep characteristics of concrete mixtures containing aggregate of maximum size greater than 2 in. (50 mm) may be determined from the creep characteristics of the minus 2-in. (minus 50-mm) fraction obtained by wet-sieving. Multiply the value of the characteristic by the ratio of the cement paste content (proportion by volume) in the full concrete mixture to the paste content of the sieved sample.
The use of the logarithmic expression (Section 8) does not imply that the creep strain-time relationship is necessarily an exact logarithmic function; however, for the period of one year, the expression approximates normal creep behavior with sufficient accuracy to make possible the calculation of parameters that are useful for the purpose of comparing concretes.
There are no data that would s...
SCOPE
1.1 This test method covers the determination of the creep of molded concrete cylinders subjected to sustained longitudinal compressive load. This test method is limited to concrete in which the maximum aggregate size does not exceed 2 in. (50 mm).
1.2 The values stated in inch-pound units are to be regarded as the standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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Publication Date
09-Aug-2002
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ASTM C512-02 - Standard Test Method for Creep of Concrete in Compression
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Please contact ASTM International (www.astm.org) for the latest information.
Designation: C512 – 02
Standard Test Method for
1
Creep of Concrete in Compression
This standard is issued under the fixed designation C512; 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.
1. Scope set forth herein must be modified to more closely simulate the
anticipated curing, thermal, exposure, and loading age condi-
1.1 This test method covers the determination of the creep
tions for the prototype structure. Current theories and effects of
of molded concrete cylinders subjected to sustained longitudi-
material and environmental parameters are presented in ACI
nal compressive load.This test method is limited to concrete in
3
SP-9, Symposium on Creep of Concrete.
which the maximum aggregate size does not exceed 2 in. (50
3.3 In the absence of a satisfactory hypothesis governing
mm).
creep phenomena, a number of assumptions have been devel-
1.2 The values stated in inch-pound units are to be regarded
oped that have been generally substantiated by test and
as the standard.
experience.
1.3 This standard does not purport to address all of the
3.3.1 Creep is proportional to stress from 0 to 40 % of
safety concerns, if any, associated with its use. It is the
concrete compressive strength.
responsibility of the user of this standard to establish appro-
3.3.2 Creep has been conclusively shown to be directly
priate safety and health practices and determine the applica-
proportional to paste content throughout the range of paste
bility of regulatory limitations prior to use.
contents normally used in concrete. Thus, the creep character-
2. Referenced Documents
istics of concrete mixtures containing aggregate of maximum
2
size greater than 2 in. (50 mm) may be determined from the
2.1 ASTM Standards:
creepcharacteristicsoftheminus2-in.(minus50-mm)fraction
C39/C39M Test Method for Compressive Strength of Cy-
obtained by wet-sieving. Multiply the value of the character-
lindrical Concrete Specimens
istic by the ratio of the cement paste content (proportion by
C192/C192M Practice for Making and Curing Concrete
volume) in the full concrete mixture to the paste content of the
Test Specimens in the Laboratory
sieved sample.
C470/C470M Specification for Molds for Forming Con-
3.4 The use of the logarithmic expression (Section 8) does
crete Test Cylinders Vertically
not imply that the creep strain-time relationship is necessarily
C617 Practice for Capping Cylindrical Concrete Specimens
an exact logarithmic function; however, for the period of one
C670 Practice for Preparing Precision and Bias Statements
year, the expression approximates normal creep behavior with
for Test Methods for Construction Materials
sufficient accuracy to make possible the calculation of param-
3. Significance and Use
eters that are useful for the purpose of comparing concretes.
3.5 There are no data that would support the extrapolation
3.1 This test method measures the load-induced time-
of the results of this test to tension or torsion.
dependent compressive strain at selected ages for concrete
under an arbitrary set of controlled environmental conditions.
4. Apparatus
3.2 This test method can be used to compare creep poten-
4.1 Molds—Molds shall be cylindrical conforming to the
tials of different concretes. A procedure is available, using the
provisions of Practice C192/C192M, or to the provisions of
developed equation (or graphical plot), for calculating stress
Specification C470/C470M. If required, provisions shall be
from strain data within massive non-reinforced concrete struc-
made for attaching gage studs and inserts, and for affixing
tures. For most specific design applications, the test conditions
integral bearing plates to the ends of the specimen as it is cast.
4.1.1 Horizontal molds shall conform to the requirements of
1
This test method is under the jurisdiction of ASTM Committee C09 on
the section on horizontal molds for creep test cylinders of
Concrete and ConcreteAggregates and is the direct responsibility of Subcommittee
Practice C192/C192M. A horizontal mold that has proven
C09.61 on Testing for Strength.
satisfactory is shown in Fig. 1.
Current edition approved Aug. 10, 2002. Published October 2002. Originally
published as C512 – 63 T. Last previous edition C512 – 87 (1994). DOI: 10.1520/ 4.2 Loading Frame, capable of applying and maintaining
C0512-02.
the required load on the specimen, despite any change in the
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
3
Standards volume information, refer to the standard’s Docu
...

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