Using trailers that have just delivered hot mix to the paving crew to then collect millings further up in the work zone is an efficient way to manage equipment. That efficiency breaks down, though, when the truck gets back to the plant and workers have to use a backhoe to scrape stuck millings out of the bed.
What’s worse is when the truck driver fails to get all the material out before he heads for the silo to get another load of on-spec mix. That’s not top quality material in his bed anymore.
A hot truck bed—about 170 degrees F after unloading—isn’t the best place to pour asphalt millings. We have little choice on big projects with multiple haul trucks running back and forth to the plant. With the preservation and maintenance projects all over the country, mill and fill is happening more and more. To increase their quality paving on an Alabama highway, the crew I worked with at APAC Midsouth came up with a great way to keep millings from sticking in their hot haul truck beds. The crew now doubles up on release agent spraying.