TM 5-822-9/AFM 88-6, Chap.10
proper conditions are provided as described herein.
seasonal air temperatures are above 90 degrees F,
Generally pavement repairs with epoxy materials
repairs should be scheduled in early morning or the
shall not be initiated unless the air and pavement
areas should be protected from direct sunlight prior
temperatures are above 40 degrees F and rising.
to initiating repair operations. High air temperature
Class A epoxy resin shall be used if the temperature
(90 degrees F and above) will decrease the working
is below 40 degrees F.
time for placement of epoxy resin mortars and
5. Approved epoxy materials. Many epoxy
epoxy resin concretes. When pavement
resins for repairing rigid pavement are available
temperatures are less than 50 degrees F, infrared
under a variety of trade names. Selection of the
heat lamps or other suitable heat sources should be
proper epoxy resin is required to obtain satisfactory
placed over the area to be repaired for
results for the work described in this manual.
approximately 3 hours prior to placement
Epoxy resins shall conform to the American Society
operations. Gentle winds can make the heat lamps
for Testing and Materials (ASTM) C 881. This
ineffective; therefore, temporary windbreaks should
ASTM specification designates three types, grades,
be used as necessary. The raising of the pavement
and classes of epoxy resins. Type I is used to bond
temperature by the use of heat lamps reduces the
hardened concrete and other materials to hardened
heat loss into the pavement and permits a desirable
concrete; Type II is used to bond freshly mixed
concrete to hardened concrete; Type III is used to
moderate heat buildup from the exothermic reaction
bond skid-resistant materials to hardened concrete,
which occurs when the two components of the
and as a binder in epoxy resin mortars or epoxy
epoxy system are combined. Although a
resin concretes. A bond strength of 1,400 pounds
satisfactory repair can be obtained if this moderate
per square inch (psi) shall be used for Type III in
heat buildup does not occur, the lack of moderate
lieu of the 300 psi shown in Table 1 of ASTM C
heat buildup may prolong a satisfactory cure-out or
881. The three grades are defined according to
hardening and thereby delay reopening to traffic.
viscosity: Grade 1-low viscosity, Grade 2-medium
Similarly, the cure-out or hardening period for
viscosity, Grade 3-nonsagging consistency or high
epoxy resin concretes and mortars can be
viscosity. Grade 3 is used primarily on vertical
accelerated during cool weather by the use of
faces. The three classes are defined according to the
heated enclosures over the repaired area. The
range of temperatures for which they are suitable:
method of attaining the desired air temperature in
Class A for use below 40 degrees F, Class B for use
the enclosure must avoid creating localized hot
between 40 and 60 degrees F, and Class C for use
spots which may cause bubbling of the liquid
above 60 degrees F.
epoxies and also induce cracking. The best method
6. Applications. The general applications or in-
for heating an enclosed area is to circulate heated
tended uses of the materials are as follows:
air with added precautions to ensure surface
a. Type I. Used for cementing dowels in drilled
and preformed holes and for pressure grouting of
temperatures in the repaired areas do not exceed
nonworking cracks. Grade 1 shall be used for
100 degrees F during the hardening stage.
pressure grouting.
b. Conditioning of aggregates. In the prepara-
tion of epoxy resin concretes and mortars, aggre-
freshly mixed portland cement concrete (PCC) to
gates should be dry and conditioned to a tempera-
hardened PCC. Grade 2 is preferred, but Grade 1
ture of 70 to 85 degrees F. The moisture content of
can be used.
the aggregates should not exceed 1.0 percent by
c. Type III. Used as a binder in epoxy resin
weight of the aggregates. The addition of epoxy
mortars or epoxy resin concretes for repairing
material to cold aggregates will result in increased
spalls and for filling nonworking joints.
viscosity and decreased stability of the mixture.
7. Effective temperature and conditioning.
Low temperatures of the final mixture will be
a. Pavements. Paragraph 5 presents the three
conducive to a reduced hardening rate. If the
classes of epoxy resins defined according to tem-
aggregates are too hot, the epoxy-curing agent
perature. If pavement and atmospheric tempera-
reaction will be accelerated, making placement and
tures are less than 70 degrees F but not below 50
finishing difficult and possibly resulting in cracking.
degrees F, satisfactory repairs can be obtained
c. Conditioning of epoxy resin components. The
without creating an artificial environment, provided
viscosity of the two components of an epoxy resin
the slightly increased cure time can be tolerated.
increases as temperatures decrease. In order to
The artificial environment can be a suitable
readily obtain a homogeneous mixture of the two
temporary structure designed to provide the
components, the materials should be conditioned to
minimum specified temperature for repairs. If
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