LEADCAP - Highway 6, Iowa City, IA

Traffic driving over the newly constructed road

On September 9, 2013, 1.5-inch LEADCAP surface mix and 1.5-inch HMA intermediate was applied to overlay the severely damaged concrete pavement on State Highway 6 with heavy truck traffic. Thirty eight percent of RAP materials was incorporated into the surface mixture with a total PG 64-28 binder content of 5.4%. Production temperature of this mix design (270 degrees F) was monitored carefully at the plant and onsite as it was compacted at around 240 degreeF. QC testing on this test section resulted in 2.8% air voids. Average percent density of six field cores was 93.9% (92.9%, 94.0%, 93.3%, 94.6%, 94.6%, 94.1%). Average temperature of HMA.was 330°F. 

As can be seen from the figure below, the fumes from the LEADCAP mixture (left) as loaded to the paver was significantly less than that of HMA (right).

LEADCAP asphalt mixture being poured with very little fumes coming off         Hot Mix Asphalt being poured with lots of fumes coming off