ASTM C1857/C1857M-19

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: C1857/C1857M − 19
Standard Test Method for
Evaluating the Adhesion (Pull-Off) Strength of Concrete
Repair and Overlay Mortar
This standard is issued under the fixed designation C1857/C1857M; 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 1.5 This international standard was developed in accor-
dance with internationally recognized principles on standard-
1.1 This test method is suitable for laboratory use to
ization established in the Decision on Principles for the
determine one or more of the following:
Development of International Standards, Guides and Recom-
1.1.1 The bond strength of a repair or an overlay material to
mendations issued by the World Trade Organization Technical
a specific concrete substrate.
Barriers to Trade (TBT) Committee.
1.1.2 The tensile strength of a repair or overlay material
after the material has been applied to the concrete substrate.
2. Referenced Documents
1.1.3 The change in bond strength when applying a bonding
agent or other bond modifying treatment to the concrete
2.1 ASTM Standards:
substrate.
C125 Terminology Relating to Concrete and Concrete Ag-
gregates
1.2 The values stated in either SI units or inch-pound units
are to be regarded separately as standard. The values stated in C191 TestMethodsforTimeofSettingofHydraulicCement
by Vicat Needle
each system are not necessarily exact equivalents; therefore, to
ensure conformance with the standard, each system shall be C305 Practice for Mechanical Mixing of Hydraulic Cement
Pastes and Mortars of Plastic Consistency
used independently of the other, and values from the two
systems shall not be combined. Some values have only SI units C702/C702M Practice for Reducing Samples of Aggregate
to Testing Size
because the inch-pound equivalents are not used in practice.
1.2.1 If required results obtained from another standard are C881/C881M Specification for Epoxy-Resin-Base Bonding
not reported in the same system of units as used by this test
Systems for Concrete
method, it is permitted to convert those results using the C900 Test Method for Pullout Strength of Hardened Con-
conversion factors found in the SI Quick Reference Guide. crete
C1107/C1107M Specification for Packaged Dry, Hydraulic-
1.3 The text of this test method refers to notes and footnotes
Cement Grout (Nonshrink)
that provide explanatory material. These notes and footnotes
C1583/C1583M Test Method for Tensile Strength of Con-
(excluding those in tables and figures) shall not be considered
crete Surfaces and the Bond Strength or Tensile Strength
as requirements of this test method.
of Concrete Repair and Overlay Materials by Direct
1.4 This standard does not purport to address all of the
Tension (Pull-off Method)
safety concerns, if any, associated with its use. It is the
E4 Practices for Force Verification of Testing Machines
responsibility of the user of this standard to establish appro-
E74 Practices for Calibration and Verification for Force-
priate safety, health, and environmental practices and deter-
Measuring Instruments
mine the applicability of regulatory limitations prior to use.
2.2 ISO Standards:
(Warning—Fresh hydraulic cementitious mixtures are caustic
ISO 13007-2 CeramicTiles - GroutsAndAdhesives - Part 2:
and may cause chemical burns to skin and tissue upon
Test Methods For Adhesives
prolonged exposure.)
This test method is under the jurisdiction of ASTM Committee C09 on
Concrete and ConcreteAggregates and is the direct responsibility of Subcommittee For referenced ASTM standards, visit the ASTM website, www.astm.org, or
C09.25 on Organic Materials for Bonding. contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Current edition approved Dec. 1, 2019. Published March 2020. DOI: 10.1520/ Standards volume information, refer to the standard’s Document Summary page on
C1857_C1857M-19. the ASTM website.
2 5
Annex A in Form and Style for ASTM Standards, www.astm.org. Available from International Organization for Standardization (ISO), ISO
Section on Safety Precautions, Manual of Aggregate and Concrete Testing, Central Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier,
Annual Book of ASTM Standards, Vol. 4.02. Geneva, Switzerland, http://www.iso.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1857/C1857M − 19
3. Terminology 5.3 The method may also be used to evaluate the perfor-
mance of bonding agents.
3.1 Definitions:
3.1.1 For definitions of terms used in this test method, refer 5.4 This test method is designed to evaluate bond strengths
to Terminology C125. in the laboratory and to standardize conditions that permit
3.2 Definitions of Terms Specific to This Standard: comparisonofresultsbetweenlaboratories.Itisnotintendedto
3.2.1 burn-in layer, n—a thin layer of repair material that is determine bond strength for field applications as results ob-
appliedforciblywithatrowelsoastopushthematerialintothe tained are only applicable to the standard substrate.
pores of the substrate.
6. Apparatus
3.2.2 scrub coat, n—a slurry applied to a concrete substrate
to enhance the bonding of a repair material to the substrate. 6.1 Rigid Disk, steel or aluminum cylindrical disk at least
50 mm [2.0 in.] diameter with thickness as follows.
3.2.3 standard concrete panel, n—a panel of concrete with a
6.1.1 Steel Disk, the thickness of a rigid disk made from
specifiedthickness,moisturecontent,waterabsorptionrateand
steel shall be at least 50 % of the diameter of the disk.
tensile strength as defined in ISO 13007-2.
6.1.2 Aluminum Disk, the thickness of a rigid disk made
3.2.3.1 Discussion—Mixture proportions and instructions
from aluminum shall be at least 60 % of the diameter of the
for manufacture of the standard panel are also included in ISO
disk.
13007-2.
6.2 Tensile Loading Device, with a load-indicating system
3.2.4 puck, n—the cylindrical specimen formed by casting
capable of applying a concentric load to the disk at the
the repair or overlay material into the cavity of the flexible
specified rate. The loading device must couple to the disk and
mask.
align to apply tension normal to the test surface. The device
shall be capable of measuring the load to the nearest 0.1 kN
4. Summary of Test Method
[20 lbs] and capturing the peak load.
4.1 This test method is performed by pulling off a puck of
NOTE 2—The tensile loading device is also referred to as a “pull-off
concrete repair or overlay material after it has been applied to
tester.”
a standard concrete panel
6.2.1 Within the operating range, the indicated tensile force
4.2 The test specimen or puck is formed by placing the
shall be within 62 % of the force measured by a calibrated
material to be evaluated inside the cavities of a flexible mask
testing machine or load cell that has been verified in accor-
that is laid on the standard concrete panel.
dance with Practices E4 or E74.
NOTE 1—As the puck is small in size, bond interface stresses due to
puck shrinkage are also small. For this reason, the test method would not 6.2.2 Verify the tensile loading device at least once a year
be a good predictor of bond failures caused by shrinkage stresses within
and after repairs and adjustments.
the repair material.
NOTE 3—See Test Method C900 for suitable verification schemes.
4.3 A rigid disk is adhered to the puck with a suitable
6.2.3 Useacouplingdevicetoconnectthedisktothetensile
adhesive.
loading device. The spherical coupling device shall be able to
4.4 A tensile load is applied to the rigid disk at a constant
withstand the tensile load capacity without yielding, and
stress rate until failure occurs. Normally, this is accomplished
transmit the tensile force in line with the axis of the puck
with a tensile loading device capable of applying a load at a
without imparting torsion or bending to the puck.
specified rate. The failure load and the failure mode are
6.3 Flexible, non-absorptive mask with 16 circular cavities.
recorded and the nominal tensile stress at failure is calculated.
Mask is nominally 6 mm [0.25 in.] thick and of similar lateral
4.5 This method is similar to Test Method C1583/C1583M
dimensions to the standard concrete panel. The diameter of the
but differs in that this method requires the use of a standard
cavities shall not be less than the diameter of the rigid disk to
concrete panel and does not require partial-depth coring of the
be used and can be up to 2 mm [0.08 in.] greater than the disk
concrete panel.
diameter. Mask cavities shall be at least 25 mm [1 in.] from the
panel edges and the clear distance between cavities shall be at
5. Significance and Use
least 40 mm [1.6 in.].
NOTE 4—Rubber and silicone have been used to make suitable masks.
5.1 When the test is performed on the repair or overlay
The diameter of the cavity is required to be equal to or up to 2 mm
material, the result is the bond strength to the concrete panel or
[0.08 in.] larger than the diameter of the rigid disk to facilitate centering
the tensile strength of either the overlay or concrete panel,
when the disk is bonded to the puck.
whichever is weaker.
7. Materials
5.2 The measured strength is controlled by the failure
mechanism requiring the least stress. Thus, it is not possible to
7.1 Standard concrete panel as defined in ISO 13007-2.
know beforehand which strength will be measured by the test.
7.2 Repair or overlay material prepared in accordance with
For this reason, the failure mode has to be reported for each
the manufacturer’s instructions.
individual test result, and tests results are averaged only if the
same failure mode occurs.Alternatively, one can infer that the 7.3 Rapid curing adhesive material for bonding the rigid
bond strength is greater than the failure stress if the bond does disk to the puck capable of providing adequate strength to
not fail during
...