Better Roads Digital Magazine
Issue link: https://read.dmtmag.com/i/85910
HighwayContractor By: Mike Anderson ome asphalt paving contractors run their own trucks; others gladly leave that task up to their subcontractors. Regardless, the hauling of mix is, we dare to say, a necessary evil. "At some point," says Volvo Construction Equipment's John Sunkenberg, "you just have to put a load of asphalt on rubber. It's the only way to get it from the plant to the paver." Fellow industry vet- eran Bill Rieken, paver applications specialist with Terex Roadbuilding, readily admits he'd just as soon never again see a conventional square- or rectangular-bodied dump truck back up to a paver or material transfer vehicle. "Conventional dump trucks are part of the problem of S temperature differential and material segregation. They only contribute to the problem; they are not part of the solution," he says. A long hauling distance combined with a low ambient temperature can result in material coming out of the truck in Live-Bottoms: "You're moving the material more as a mass horizontally, rather than verti- cally, and that's a good thing." -John Sunkenberg, Volvo Construction Equipment cold clumps in need of extensive re-mixing or re-blending – a scenario only exasperated by an end dump. "When you raise that truck bed, you generally have material break- ing and running in the hopper," says Sunkenberg, Volvo road industry competency manager, "and you can deal with segregation on the sides and the corners." "If we're forced to use dump trucks," says Rieken, "what some contractors will do is make you put in deflector plates in the back so the discharge area is the same width as the slats or the augers you are feeding, so you get some re-blending of the mix as you dump it out of that truck. This way, you're not held to the pav- er too long. Otherwise, the mix that sits in the hopper wings prevents the truck from getting empty quickly, and you end up holding the truck." Even before considering the material unloading is- sues, including the safety hazards of lifting an end dump bed on uneven terrain or near overhead wires, the ba- sic geometry of the hauling space itself is an issue with Better Roads February 2012 11