Pavement engineers everywhere, take note.  The warm mix vs. hot mix asphalt showdown has begun. 

SDOT just finished paving 4^th Ave S. in the SODO area last night with a new, lower temperature asphalt mix.  This new asphalt mix reduces fuel consumption and greenhouse gas emissions.

The temperature drop out of the back of the paver the past two nights was impressive: 250° instead of about 300° with the standard mix.  The warm mix did prove a little stiffer than hot mix and required more effort to rake.  However, the finished handwork looked great. We’re waiting for the lab tests, but so far the material is meeting all standards.

Equally exciting is that early estimates indicate a reduction in fuel consumption approaching 20% at the plant.  Good for the environment and good for our project costs.

Positive initial results, but the proof is in the pudding.   We’ll continue testing and monitoring how it performs over time.  Hot mix, don’t let your guard down.

Raking the new warm mix asphalt