Spray Applied Polymer Surface Seals - TSP2

Lessons Learned
Pavement Permeability
Emulsion Infiltration
Pavement permeability
• Pre-seal – Will emulsion infiltrate surface?
Impacts emulsion application rate
Effectiveness of seal
• Post-seal - Will seal protect the surface from
moisture & air infiltration?
Performance over time
Emulsion infiltration
• Particle size, surface tension, viscosity
Impacts emulsion application rate
Effectiveness of sealer / rejuvenator
Ideal penetration depth: ½” for dense HMA
To be effective, fog seal emulsions must infiltrate into the pavement surface. It was
hoped that permeability would be a key measure for both determining application
rate of sealers and their effectiveness over time. While there is probably an ideal
emulsion viscosity for adequate film thickness and infiltration into a pavement, the
surface tension of the emulsion is a better indicator of the ability of the emulsion to
infiltrate the surface. Because this testing was initiated very late in the study, there
was insufficient data collected to reach definitive conclusions about optimal surface
tension. Similarly, the particle size of the emulsion should equate with its ability to
enter small pores in the pavement surface. Emulsified rejuvenator oil particles
should be easier to deform and enter pores than higher viscosity asphalt droplets.
However, only limited particle size data was collected for this study.
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