US FEDERAL SPECIFICATION: SEALANTS, JOINT, TWO-COMPONENT, JET-BLAST-RESISTANT, COLD-APPLIED, FOR PORTLAND CEMENT CONCRETE PAVEMENT
a.
Type M - Machine application, fast curing
b.
Type H - Hand mixed, retarded cure
1)
The sealant shall be a combination of two
component materials, a base and a curing agent.
2)
The mixture of the materials shall be black.
3)
The mixture shall cure to form a resilient and adhesive
elastomeric compound which is resistant to the solvent action of jet fuel and
lubricating oils, and to the direct heat and blast of aircraft engines.
4)
The sealant shall effectively seal joints and
cracks in pavements against the infiltration of moisture and jet fuel
throughout repeated cycles of expansion and contraction, and shall not flow
from the joints or be picked up by pneumatic tires at in-place joint seal
temperatures of 60 degrees Celsius (deg C) (140 degrees Fahrenheit (deg F)) or
below.
5)
The mixed material shall have a uniform
application or pouring consistency suitable for completely filling the joint
without inclusion of blisters, bubbles, or discontinuities.
6)
Material shall be applicable at ambient
temperatures of 4 deg C (40 deg F) and above.
7)
When material is applied at ambient temperatures
of 16 deg C (60 deg F) and above, it shall cure to permit traffic on the
pavement within 3 hours after application of type M, or 12 hours after
application of type H, without wheel pickup.
7)
ü
Component A (curing agent). Component A shall
activate the polymer system to end point when mixed with component B.
ü
Component B (base resin). Component B shall be a
homogeneous mixture of polymer and filler, with activators, plasticizers,
gelling agents
ü
Primer is recommended by the manufacturer for a
specific surface, all tests and applications concerning adhesion shall include the
primer, applied in accordance with instructions provided by the manufacturer.
Primers shall be formulated to cure in not more than 1 hour, and shall remain
active for not less than 4 hours after application.
a.
Sealant shall be formulated for application with
pressurized mixing and extruding equipment. The equipment shall deliver the
components in the required ratio plus or minus 5 percent variation.
b.
Mixing ratio: Component A and component B shall
be supplied in pre-proportioned containers, in a volume ratio of 1:1.
c.
The viscosity of component A and component B,
each shall not exceed 200 pascal seconds (Pa.s) (200,000 centipoise (cP))
d.
Working life of the homogeneous mixture of
sealant shall be formulated for time duration allowing use of the specified
equipment to mix and extrude the material and to seal a prepared concrete
joint.
e.
The tack-free time shall not exceed 3 hours
after application.
a.
The sealant shall be formulated for manual
slow-speed electric or air-driven mixing, and pouring or extruding application.
b.
Mixing ratio: Component A and component B shall
be supplied in preproportioned containers.
c.
The viscosity of component A and component B
each shall not exceed 150 Pa.s (150,000 cP)
d.
The working life of the homogeneous mixture of
sealant shall be not less than 3 hours after mixing, as evidenced by viscosity
not exceeding 200 Pa.s (200,000 cP).
e.
The tack-free time shall not exceed 12 hours
after application.
Performance:
i.
Accelerated aging - no visual or physical change
during accelerated aging in sealed containers.
ii.
Self-leveling –
a.
Extruded or poured into a joint on a level
plane, shall flow to a variation of the surface not greater than 3.2mm (0.125
inch)
b.
Extruded into a joint on a 1.5 percent incline,
shall limit flow to a depth variation not-greater than 1.6 mm (0.063 inch).
iii.
Change in mass by fuel immersion
a.
Dry mass of the sealant after fuel immersion for
24 hours at 49 deg C (120 deg F) shall not exceed 2.0 percent.
b.
No apparent defects that will affect the
material as a sealant
iv.
Change in volume on exposure to elevated
temperature - When exposed to 70 deg C (158 deg F) for 168 hours shall not
exceed 5.0 percent
v.
Resilience:
a.
Recovery shall be a minimum of 75.0 percent
b.
The initial penetration shall not exceed 2.0 mm
(0.079 inch) and shall not be less than 0.5 mm (0.020 inch).
vi.
Artificial weathering - 160 hours of artificial
weathering shall not show surface softening, presence of an oil-like film,
reversion to a mastic-like substance, formation of surface blisters exceeding
the specified size and density, or an average change in volume exceeding 5.0
percent
vii.
Bond to concrete - None of the specimens shall
develop any surface checking or crazing, crack, separation, or other opening in
the sealant, or between the sealant and the concrete blocks, and there shall be
no surface hardening or loss of resilient, rubber-like characteristics in the
sealant.
viii.
Flame resistance - sealant shall not show any
evidence of ignition, support of combustion, hardening or loss of flexibility,
flow, or separation during heat exposure, or upon examination after cooling, or
any separation or loss of adhesive strength between sealant and concrete
blocks, when exposed to 260 deg C (5OO deg F) for 120 seconds
ix.
Flow - sealant shall show no evidence of
cracking, sag, or dimensional change, after 5 hours of exposure to 93 deg C
(200 deg F)
x.
Storage stability - sealant materials, when
stored in full, tightly closed containers for 6 months from the date of
delivery, at temperatures from 16 to 38 deg C (60 to l00 deg F), away from
direct sunlight and weather exposure.
xi.
Toxicity - The material shall have no adverse
effect on the health of personnel when used for its intended purpose.
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