Hot job summer: The asphalt pavement process

 

By Tim Potter, 
District Five Public Affairs Manager 

Imagine this: You’re under a blinding sun along U.S. 50 near the town of Walton, and the combined heat and humidity makes it feel like around 106 degrees. It’s suffocatingly hot, the kind of conditions that trigger a heat advisory.

Not just that: You’re laying down asphalt cooking at around 250 degrees when you first apply it. The stiff south wind feels like more of a blast furnace than a cooling breeze. You’ve worked through lunch because overlaying a side road at a highway is one of those jobs where it’s not real practical to take a normal 30-minute break. The equipment has been strategically positioned, and the different tasks involved must click right along. The asphalt -- and the process for applying, shaping and finishing it -- is demanding, unforgiving.

That is what it was like for a combined team of crew members – from the Newton Subarea, District Special Crew and El Dorado Area and El Dorado Subarea -- the afternoon of July 28. If you had to visit one of the hottest KDOT jobs on an extra sweltering day, this was it. They had been overlaying side roads for almost two weeks.

Sweat beads covered the reddened face of Bobby Jones that afternoon as he matter-of-factly explained the work being done and the reality of enduring merciless weather.

“The hotter it is, the nicer it lays,” Jones said of the asphalt. “You have to work it while the asphalt’s hot.” The Newton Subarea Supervisor watched a massive roller compact the new surface. Even though they had paving machines, some of the finishing and clean-up tasks must be done by hand, by bending over a shovel and pushing and lifting.

Through it all, “You have to drink lots of fluids; otherwise, you’ll be laid out on top of the asphalt,” Jones said. “If you don’t keep hydrating, this heat will take it right out of you in a heartbeat.”

Everyone had a different role in the overlay job, and part of it was paying attention to their co-workers – operators making sure they didn’t drive over someone, everyone staying aware of the semis barreling past only feet away, everyone making sure that the next person wasn’t overcome by the heat.

“This is a team effort,” Jones said. “We all have to watch out for each other.”

Kansas highways win national awards

 This award winning section of  U.S. 160 extends from the U.S. 160/U.S. 54 junction in Meade County to the U.S. 160/U.S. 283 junction in Clark county

Kansas highways continue to win national recognition. APAC Shears of Hutchinson has 

received three awards from the National Asphalt Pavement Association (NAPA) for projects in Kansas.

The APAC Hays Branch was awarded the Larry H. Lemon Quality in Construction Award for a mill and overlay project on U.S. 160 that extends from the U.S. 160/U.S. 54 junction in Meade County to the U.S. 160/U.S. 283 junction in Clark county. The award recognizes asphalt pavements that use less than 50,000 tons of asphalt in the project.

The $1.4 million project was 17 miles in length and completed in June.

“We are proud of the great work our contractors do for the state of Kansas,” said Catherine Patrick, State Transportation Engineer for the Kansas Department of Transportation (KDOT).

Award-winning section of U.S. 50 in Harvey County

The APAC Heavy Highway Branch of Hutchinson received two awards - one for U.S. 50 in Harvey County in the category of projects with 50,000 tons or less asphalt, and one for U.S. 69 in Linn County in the category of projects of 50,000 tons or more asphalt.

“A Kansas asphalt contractor achieving this award is testimony of the high-quality work performed by our producer members,” said Dan Scherschligt, Executive Director of the Kansas Asphalt Pavement Association.

An in-progress photo of U.S. 69 in Linn County, which won an award from the National Asphalt Pavement Association. 

According to APAC Shears, the pavement went through a variety of tests and were compared for volumetric quality and hitting targets for air voids, density and gradation and measurements of quality pavements.    

KDOT’s Director of Operations Larry Thompson said that KDOT and the state of Kansas benefit from contractors who are able to provide quality roads.

Waste not, want not

Is pig poop the future of pavement?

We have all heard the story of the three little pigs. That third little pig was an engineering pro who stopped the Big Bad Wolf from blowing his house down. That was a great story, but what pigs could do for the future of transportation is no fairy tale.

Although still in the testing stage, students at North Carolina A&T State University and the National Science Foundation have teamed up to explore the possibilities of using pig manure as a binder, or bio-adhesive, for an asphalt substitute. Currently, asphalt requires petroleum, which is a fossil fuel and cannot be replenished as quickly. 

With asphalt created with bio-adhesives, the opposite is true.  According to a video produced by the NSF, 43 billion pounds of swine manure is generated in one year. In fact, some places in the world have so much pig waste that their water supplies are being contaminated.  At 56 cents per gallon this renewable resource could pave the road for a more environmentally and financially-sound solution to fossil fuel dependency. 

It’s not just the transportation industry that could benefit from successful bio-adhesive roads; the farming industry around the world would still be able to use the leftovers from the manufacturing process as fertilizer.

Think this idea is full of it? Check out The National Science Foundation’s video for a closer look at how the process is being tested. And tell us what you think. Would you be willing to travel down a road made from pig poop?