The theory, says Humphrey, is to get through the first third of that particular phase of the project in less than one-third of the phase’s allotted time. “I balance plant output, trucking, paving speed and compaction, so that in that first pass, I can go as fast as I can get the mix to it, without stopping and without outrunning the compactors. Then I’ve got myself a little breathing room moving forward.”

The vehicle volume factor

Ironically often the political reason for paving at night, reduced traffic, actually represents an advantage to efficient night paving, “because the traffic is what really hinders continuous paving,” says Terex Roadbuilding’s Rieken. “During the day, you might have a plant that has sufficient production, you might have adequate trucks, but the traffic still might hinder the flow of trucks to and from the jobsite, so the night paving if anything probably lends to the success of the continuous paving process, because there is less traffic.”

Says Humphrey: “The paver itself doesn’t care how fast you pave, as long as you’re consistent and don’t have long stops … and the compaction process can match you. So, you plan all that before you go to work. You make the calculations.” Adds Sunkenberg: “If you’re on a continuous paving job at night and the paving train stops, they’re upset, because the profilograph will pick up a stop and it will count against their final score and will ultimately cost them money.”

On the con side of the night paving equation is increased cost, says Rieken. “To ensure the safety of the paving crew and the operation, and of the people driving on the road, it takes more people, more equipment to make that happen, so there is a cost incurred that would probably be the biggest downside of doing it at night.” Which leads to another suggestion from the veteran trainer Humphrey: “Fatigue plays a huge role in night paving. I’d suggest trying to figure out a way if I can overstaff by one person. ‘Can I give people a chance to actually stop work for a minute, get a cup of coffee and stagger out a little bit, so they don’t get quite as fatigued, lose their focus, because that’s when mistakes happen?’

“If you have a long night project, I think you’re almost better off having one crew doing it instead of switching crews on and off nights,” says Humphrey, “so they might have a chance to acclimate to working at night and resting during the day.”

A safe work environment – and Sunkenberg has worked with night paving contractors who ensure reflective tape is wrapped around anything and everything on site – is the only thing that ultimately matters, says Humphrey.

“The residents, the business owners, nobody likes to have construction going on,” he says. “I’m not too sympathetic to that.

“We have to be able to see out there … and we’re going to make a certain amount of noise.” v