Tennessee DOT uses innovation to rebuild Nashville’s I-440

Historic project converted concrete pavements to asphalt 

By Bob Horan, P.E.

A reconstructed section of the I-440 corridor which is part of the loop around Nashville, Tennessee from I-40 to I-24 was opened in July 2020 – a full month ahead of schedule.

That was very good news for the approximately 110,000 drivers that use this roadway daily as it is now safer and less congested than the old roadway. The cost of the design-build project was $154 million which made it the largest reconstruction project ever by the Tennessee Department of Transportation (TDOT). 

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Effectively curtail oxidation with warm mix asphalt

By Amma Wakefield, P.Eng. 

A couple of years ago, I was preparing a talk on “What happened to warm mix asphalt?” and I remember getting stuck on the presentation outline in a daydream… 

Once upon a time, technical asphalt conferences showcased countless WMA research findings from the lab and field. I happily added my master’s thesis to the knowledge pool when I researched material properties of HMA and chemically-modified WMA. 

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