Using Polymer Modified Asphalt Emulsions in Surface Treatments A ...
Using Polymer Modified Asphalt Emulsions in Surface Treatments A ...
Using Polymer Modified Asphalt Emulsions in Surface Treatments A ...
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However, <strong>in</strong> develop<strong>in</strong>g the SPG, Epps generally discounts the importance of rutt<strong>in</strong>g<br />
and thermal crack<strong>in</strong>g <strong>in</strong> surface treatments, focus<strong>in</strong>g <strong>in</strong>stead on:<br />
1. High and low temperature behavior which can lead to aggregate loss;<br />
2. Ag<strong>in</strong>g performance;<br />
3. Application and handl<strong>in</strong>g characteristics of the prepared emulsion (57).<br />
Conversely, rutt<strong>in</strong>g resistance can prove a valuable test parameter when assess<strong>in</strong>g the<br />
performance of rut-fill<strong>in</strong>g mixes (54). Takamura has observed that the action of radial<br />
truck tires actually produces higher than average critical shear stresses on th<strong>in</strong> surface<br />
treatments such as chip seals and microsurfac<strong>in</strong>gs, as compared to full or partial<br />
thickness HMA (see Figure 18). This underscores the importance and value of<br />
estimat<strong>in</strong>g the high temperature susceptibility and stone retention capacity of modified<br />
surface treatments.<br />
Figure 18: Influence of Radial Tire on <strong>Surface</strong> Treatment (54)<br />
It is noteworthy that the relationships between laboratory-determ<strong>in</strong>ed b<strong>in</strong>der physical<br />
properties and actual field performance are not always clear, and substantial evidence<br />
exists which is often contradictory. For example, it has been shown through stresscontrolled<br />
fatigue tests that stiffer mixes are more resistant to fatigue crack<strong>in</strong>g, whereas<br />
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