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: D7405 − 24

Standard Test Method for

Multiple Stress Creep and Recovery (MSCR) of Asphalt
Binder Using a Dynamic Shear Rheometer1,2
This standard is issued under the fixed designation D7405; 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 mendations issued by the World Trade Organization Technical

1.1 This test method covers the determination of percent Barriers to Trade (TBT) Committee.
recovery and non-recoverable creep compliance of asphalt
2. Referenced Documents
binders by means of multiple stress creep and recovery
(MSCR) testing. The MSCR test is conducted using the 2.1 ASTM Standards:3
dynamic shear rheometer (DSR) at a specified temperature. C670 Practice for Preparing Precision and Bias Statements
for Test Methods for Construction Materials
1.2 This standard is appropriate for unaged material, mate-
D8 Terminology Relating to Materials for Roads and Pave-
rial aged in accordance with Test Method D2872 (RTFOT),
ments
material aged in accordance with Practice D6521 (PAV), and
D2872 Test Method for Effect of Heat and Air on a Moving
material aged in accordance with both Test Method D2872 and
Film of Asphalt Binder (Rolling Thin-Film Oven Test)
Practice D6521.
D3666 Specification for Minimum Requirements for Agen-
NOTE 1—The majority of development work on this test method was
performed on material aged in accordance with Test Method D2872 cies Testing and Inspecting Road and Paving Materials
(RTFOT). D5801 Test Method for Toughness and Tenacity of Asphalt
1.3 The percent recovery is intended to provide a means to Materials
determine the presence of elastic response and stress depen- D6084/D6084M Test Method for Elastic Recovery of As-
dence of polymer-modified and unmodified asphalt binders. phalt Materials by Ductilometer
D6373 Specification for Performance-Graded Asphalt
1.4 The values stated in SI units are to be regarded as Binder
standard. No other units of measurement are included in this D6521 Practice for Accelerated Aging of Asphalt Binder
standard. Using a Pressurized Aging Vessel (PAV)
1.5 The text of this standard references notes and footnotes D7175 Test Method for Determining the Rheological Prop-
which provide explanatory material. These notes and footnotes erties of Asphalt Binder Using a Dynamic Shear Rheom-
(excluding those in tables and figures) shall not be considered eter
as requirements of the standard. 2.2 AASHTO Standards:4
1.6 This standard does not purport to address all of the M 332 Specification for Performance-Graded Asphalt
safety concerns, if any, associated with its use. It is the Binder Using Multiple Stress Creep Recovery (MSCR)
responsibility of the user of this standard to establish appro- Test
priate safety, health, and environmental practices and deter- T 350 Method of Test for Multiple Stress Creep Recovery
mine the applicability of regulatory limitations prior to use. (MSCR) Test of Asphalt Binder Using a Dynamic Shear
1.7 This international standard was developed in accor- Rheometer (DSR)
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the 3. Terminology
Development of International Standards, Guides and Recom- 3.1 Definitions—For definitions of general terms used in this
standard, refer to Terminology D8.

1
This test method is under the jurisdiction of ASTM Committee D04 on Road
3
and Paving Materials and is the direct responsibility of Subcommittee D04.44 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Rheological Tests. contact ASTM Customer Service at www.astm.org/contact. For Annual Book of
Current edition approved Oct. 1, 2024. Published October 2024. Originally ASTM Standards volume information, refer to the standard’s Document Summary
approved in 2008. Last previous edition approved in 2020 as D7405 – 20. DOI: page on the ASTM website.
4
10.1520/D7405-24. Available from American Association of State Highway and Transportation
2
This test method is based on a work product of the Federal Highway Officials (AASHTO), 444 N. Capitol St., NW, Suite 249, Washington, DC 20001,
Administration. A similar standard is published as AASHTO TP 70. http://www.transportation.org.

Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States

1
 D7405 − 24
3.2 Definitions of Terms Specific to This Standard: 8. Procedure
3.2.1 creep and recovery, n—a standard rheological test 8.1 Allow the specimen to reach thermal equilibrium at the
protocol whereby a specimen is subjected to a constant load for desired test temperature in accordance with the Test Procedure
a fixed time period then allowed to recover at zero load for a section of Test Method D7175. If the specimen has previously
fixed time period. been tested in dynamic shear, allow the specimen to remain
3.2.2 non-recoverable creep compliance (Jnr), n—the re- unloaded for at least 1 min before starting the creep and
sidual strain in a specimen after a creep and recovery cycle recovery test.
divided by the stress applied in kPa. 8.2 Creep and Recovery Cycle—Load the specimen at a
4. Summary of Test Method constant creep stress for 1.00 s duration creep and follow with
a zero stress recovery of 9.00 s duration. The commanded full
4.1 This test method is used to determine the presence of torque for each creep cycle shall be achieved within 0.003 s
elastic response in an asphalt binder under shear creep and from the start of the creep cycle as certified by the equipment
recovery at two stress levels at a specified temperature. For manufacturer. Record the stress and strain at least every 0.10 s
performance grade (PG) binders, the specified temperature will for the creep cycle and at least every 0.45 s for the recovery
typically be the PG high temperature without grade bumping as cycle on a running accumulated time such that, in addition to
determined in Specification D6373 or AASHTO M 332. other data points, data points at 1.00 s and 10.00 s for each
Sample preparation and apparatus are in accordance with Test cycle’s local time are explicitly recorded. If the DSR does not
Method D7175 using the 25 mm parallel plate geometry with record the strain at exactly 1.00 and 10.00 s then the DSR
a 1 mm gap setting. The sample is loaded at constant stress for software shall extrapolate prior data to determine the strain
1 s then allowed to recover for 9 s. Twenty creep and recovery value at the required time. Extrapolation data shall include a
cycles are run at 0.100 kPa creep stress followed by ten creep measured data point no more than 0.10 s prior to the required
and recovery cycles at 3.200 kPa creep stress. time for a creep cycle, no more than 0.50 s prior to the required
time for a recovery cycle.
5. Significance and Use
NOTE 4—If the creep and recovery curves will be used for modeling,
5.1 This test method is used to identify the presence of more frequent data points may be required.
elastic response in a binder and the change in elastic response
8.3 Allowing no rest period between cycles, perform 20
at two different stress levels. Non-recoverable creep compli-
creep and recovery cycles at a creep stress of 0.100 kPa. The
ance has been shown to be an indicator of the resistance of an
first ten cycles are for conditioning the specimen. The second
asphalt binder to permanent deformation under repeated load.
ten cycles are designated as cycles N = 1 to 10 and are used for
5.2 This test method is also useful as a surrogate for other data collection and analysis.
test methods used to measure elasticity in asphalt binders such
8.4 Allowing no rest period following 8.3 and no rest period
as Test Method D5801 (toughness and tenacity), Test Method
between cycles, perform ten creep and recovery cycles at a
D6084/D6084M (elastic recovery), and Test Method D7175
creep stress of 3.200 kPa. The total time required to complete
(DSR phase angle).
8.3 and 8.4 is 300 s.
NOTE 2—The quality of the results produced by this standard are
dependent on the competence of the personnel performing the procedure
8.5 For cycles N = 1 to 10 at the 0.100 kPa stress level and
and the capability, calibration, and maintenance of the equipment used. cycles N = 1 to 10 at the 3.200 kPa stress level, record the
Agencies that meet the criteria of Specification D3666 are generally following:
considered capable of competent and objective testing, sampling, 8.5.1 Initial strain value at the beginning of the creep
inspection, etc. Users of this standard are cautioned that compliance with portion of each cycle. This strain shall be denoted as ε0.
Specification D3666 alone does not completely ensure reliable results.
Reliable results depend on many factors; following the suggestions of 8.5.2 The strain value at the end of the creep portion (that is,
Specification D3666 or some similar acceptable guideline provides a after 1.0 s) of each cycle. This strain shall be denoted as εc.
means of evaluating and controlling some of those factors. 8.5.3 The adjusted strain value at the end of the creep
portion (that is, after 1.0 s) of each cycle, ε1, calculated as:
6. Apparatus
ε1 5 εc 2 ε0 (1)
6.1 Dynamic Shear Rheometer (DSR)—A dynamic shear
rheometer as described in the Apparatus section of Test Method 8.5.4 The strain value at the end of the recovery portion
D7175 and associated materials as described in the Materials (that is, after 10.0 s) of each cycle. This strain shall be denoted
section of Test Method D7175. The rheometer shall run in as εr.
stress control mode. The plate radius parameter shall be set at 8.5.5 The adjusted strain value at the end of the recovery
100 %. portion (that is, after 10.0 s) of each cycle, ε10, calculated as:
ε 10 5 ε r 2 ε 0 (2)
7. Preparation of Test Specimen
9. Calculation
7.1 Prepare the test specimen in accordance with the Pre-
paring Test Specimens section of Test Method D7175. 9.1 Using the results obtained in 8.5, determine the average
NOTE 3—This test may be run on a specimen previously tested in percent recovery and non-recoverable creep compliance for the
dynamic shear in accordance with the Test Procedure section of Test asphalt binder at creep stress levels of 0.100 kPa and 3.200 kPa
Method D7175. as follows:

2
 D7405 − 24
9.1.1 For cycles N = 1 to 10 at a creep stress of 0.100 kPa 9.1.8 Calculate average non-recoverable creep compliance
calculate the percent recovery, εr(0.1, N): at 0.100 kPa:
~ ε 1 2 ε 10! ·100 SUM~ J nr~ 0.1, N !!
ε r ~ 0.1, N ! 5 (3) J nr0.1 5 for N 5 1 to 10 (12)
ε1 10

9.1.1.1 If εr(0.1, N) < 0, then record εr(0.1, N) as zero. 9.1.9 Calculate average non-recoverable creep compliance
at 3.200 kPa:
NOTE 5—The measured percent recovery can be affected by character-
istics such as inertia and data sampling. These effects are more pro- SUM~ J nr~ 3.2, N !!
nounced when the recovery is small, as with many unmodified asphalt J nr3.2 5 for N 5 1 to 10 (13)
10
binders, and can result in a negative measured recovery. For the scope of
this test method, a negative recovery can be considered to be zero. These 9.1.10 Calculate percent difference in non-recoverable creep
effects are also more pronounced when the recovery is very large, as with compliance between 0.100 kPa and 3.200 kPa:
some modified asphalt binders which are highly elastic in response and
can result in a greater than 100 % measured recovery. For the scope of this ~ J nr3.2 2 J nr0.1! ·100
J nrdiff 5 (14)
test method, a measured percent recovery of greater than 100 % can be J nr0.1
considered to be 100 %.
9.1.2 For cycles N = 1 to 10 at a creep stress of 3.200 kPa 10. Report
calculate the percent recovery, εr(3.2, N): 10.1 Report the following information:
~ ε 1 2 ε 10! ·100 10.1.1 Sample identification;
ε r ~ 3.2, N ! 5 (4)
ε1 10.1.2 Test temperature, to the nearest 0.1 °C;
9.1.2.1 If εr(3.2, N) < 0, then record εr(3.2, N) as zero. 10.1.3 Average percent recovery at 0.100 kPa for the last ten
cycles, R0.1, to the nearest 0.1 %;
9.1.3 Calculate average percent recovery at 0.100 kPa:
10.1.4 Average percent recovery at 3.200 kPa, R3.2, to the
SUM~ ε r ~ 0.1, N !! nearest 0.1 %;
R0.1 5 for N 5 1 to 10 (5)
10 10.1.5 Percent difference between average recovery at
9.1.3.1 If (average percent recovery) > 100 %, then record 0.100 kPa and 3.200 kPa, Rdiff, to the nearest 0.1 %;
as 100 %. 10.1.6 Non-recoverable creep compliance at 0.100 kPa for
9.1.4 Calculate average percent recovery at 3.200 kPa: the last ten cycles, Jnr0.1, to three significant figures;
10.1.7 Non-recoverable creep compliance at 3.200 kPa,
SUM~ ε r ~ 3.2, N !!
R3.2 5 for N 5 1 to 10 (6) Jnr3.2, to three significant figures; and
10
10.1.8 Percent difference between non-recoverable creep
9.1.4.1 If (average percent recovery) > 100 %, then record compliance at 0.100 kPa and 3.200 kPa, Jnrdiff, to nearest 0.1 %.
as 100 %.
9.1.5 Calculate percent difference in recovery between 11. Precision and Bias
0.100 kPa and 3.200 kPa: 11.1 Precision—Criteria for judging the acceptability of
~~ R0.1 2 R3.2! · 100! results obtained by the multiple stress creep and recovery
R diff 5 (7)
R0.1 (MSCR) method are given in Table 1. These criteria are based
on this standard and the procedure given in AASHTO T 350.
9.1.6 For cycles N = 1 to 10 at a creep stress of 0.100 kPa
calculate the non-recoverable creep compliance, Jnr(0.1, N): 11.2 Single-Operator Precision (Repeatability)—The fig-
ures in Column 2 of Table 1 are the coefficients of variation
ε 10
J nr~ 0.1, N ! 5 (8) that have been found to be appropriate for the conditions of test
0.1
described in Column 1. Two results obtained in the same
9.1.6.1 If εr(0.1, N) was less than zero, then calculate laboratory, by the same operator using the same equipment, in
Jnr(0.1, N) as: the shortest practical period of time, should not be considered
ε1
suspect unless the difference in the two results, expressed as a
J nr~ 0.1, N ! 5 (9) percent of their mean, exceeds the values given in Column 2.
0.1
NOTE 6—If εr(0.1, N) is negative then the adjusted creep strain at 1.0 s 11.3 Multilaboratory Precision (Reproducibility)—The fig-
is the more appropriate strain value to use, as there is no recovery. ures in Column 3 of Table 1 are the coefficients of variation
9.1.7 For cycles N = 1 to 10 at a creep stress of 3.200 kPa that have been found to be appropriate for the conditions of test
calculate the non-recoverable creep compliance, Jnr(3.2, N): described in Column 1. Two results submitted by two different
operators testing the same material in different laboratories
ε 10
J nr ~ 3.2, N ! 5 (10) should not be considered suspect unless the difference in the
3.2
two results, expressed as a percent of their mean, exceeds the
9.1.7.1 If εr(3.2, N) was less than zero, then calculate values given in Column 3.
Jnr(3.2, N) as: 11.4 Bias—No information can be presented on the bias of
ε1 the procedure because no material having an accepted refer-
J nr ~ 3.2, N ! 5 (11)
3.2 ence value is available.

3
 D7405 − 24
TABLE 1 Estimated Repeatability and Reproducibility

NOTE 1—The precision estimates in this table are based on the analysis of test results from eight laboratories for eight asphalt binders. The analysis
included five binder grades: PG 64-22, PG 64-34, PG 70-28, PG 70-34, and PG 76-22. Average Jnr results varied from 0.061 to 2.498 kPa–1. Average
recovery results varied from 0 to 88.3 %.
Condition Coefficient of Variation (1s%)A Acceptable Range of Two Test Results (d2s%)A
Single-Operator Precision:
R0.1 (%) 2.4 % 6.7 %
R3.2 (%) 3.0 % 8.5 %
Jnr0.1 (kPa–1)
>1.00 4.6 % 12.8 %
0.26–1.00 5.4 % 15.2 %
0.10–0.25 13.7 % 38.3 %
<0.10B n/a n/a
Jnr3.2 (kPa–1)
>1.00 5.7 % 16.0 %
0.26–1.00 5.5 % 15.3 %
0.10–0.25 9.5 % 26.6 %
<0.10B n/a n/a
Multilaboratory Precision:
R0.1 (%) 5.4 % 15.0 %
R3.2 (%) 6.5 % 18.1 %
Jnr0.1 (kPa–1)
>1.00 9.1 % 25.6 %
0.26–1.00 12.7 % 35.6 %
0.10–0.25 16.7 % 46.8 %
<0.10B n/a n/a
Jnr3.2 (kPa–1)
>1.00 7.9 % 22.0 %
0.26–1.00 13.9 % 39.0 %
0.10–0.25 15.2 % 42.6 %
<0.10B n/a n/a
A
These limits represent the 1s% and d2s% limits described in Practice C670.
B
For Jnr values below 0.1 kPa–1, high variability is likely due to the very low strain values that are measured. If an asphalt binder has a Jnr value below 0.1 kPa–1 at a
specified temperature, then consideration should be given to testing at a temperature that is 6 °C higher.

12. Keywords
12.1 asphalt binder; creep and recovery; DSR; dynamic
shear rheometer; elastic recovery; MSCR; non-recoverable
creep compliance; polymer-modified asphalt

ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned
in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk
of infringement of such rights, are entirely their own responsibility.

This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and
if not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards
and should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the
responsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you should
make your views known to the ASTM Committee on Standards, at the address shown below.

This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,
United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above
address or at 610-832-9585 (phone), or through the ASTM website (www.astm.org/contact). Permission rights to photocopy the
standard may also be secured from the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600;
http://www.copyright.com/