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Economy | Energy & Mining | State Government | Transportation

Photo essay: Paving the way

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New asphalt for North Douglas Highway. (Photo by Matt Miller/KTOO)
Crude oil art: New asphalt for North Douglas Highway. (Photo by Matt Miller/KTOO)
The construction season normally winds down in Juneau with fall’s diminishing daylight and cooler conditions. Large pours of concrete foundations and paving of asphalt roadways are not typically done as overnight temperatures approach freezing.

One of the last big paving projects in Juneau this season was the surfacing of the deck of the new Brotherhood Bridge over the Mendenhall River, a major project that was just completed and dedicated.

I took a few pictures last summer as SECON and Alaska Department of Transportation crews passed by my house while repaving North Douglas Highway.

In the case of the resurfacing of North Douglas Highway last summer, the top layer was ground away and a tack coat of asphalt was laid down and allowed to set. (Photo by Matt Miller/KTOO)
In the case of last summer’s resurfacing of North Douglas Highway, the old top layer of the roadway was ground away and removed, and a tack coat of asphalt was laid down and allowed to set. (Photo by Matt Miller/KTOO)
A tractor trailer returns from the asphalt plant and carefully lays down asphalt mix on top of the sprayed asphalt tack coat.(Photo by Matt Miller/KTOO)
A tractor trailer returns from the asphalt plant and carefully lays down asphalt mix on top of the sprayed asphalt tack coat.(Photo by Matt Miller/KTOO)
Check out some of the sources for this photo essay:

How Stuff Works – How asphalt works – the black stuff that makes America’s car culture possible (Includes videos of asphalt mixing, laying, and milling for recycling)

Asphalt Institute – Asphalt Pavement Construction FAQs

Asphalt is the heaviest byproduct of refined crude oil and it is typically heated to temperature of 300 degrees for road construction. Above, a tractor trailer delivers a load of asphalt mix which includes aggregate or gravel of various sizes which is mixed with asphalt at a plant. (Photo by Matt Miller/KTOO)
Asphalt is the heaviest byproduct of refined crude oil and it is typically heated to temperature of 300 degrees for road construction. Above, a tractor trailer delivers a load of asphalt mix which includes aggregate or gravel of various sizes which is mixed with asphalt at a plant. (Photo by Matt Miller/KTOO)
An asphalt spreader follows the long pile of asphalt mix laid down by the tractor trailer. Speed of the spreader sometimes determines the width, height and crowning of asphalt layer. (Photo by Matt Miller/KTOO)
An asphalt spreader follows the long pile of asphalt mix laid down by the tractor trailer. Speed of the spreader sometimes determines the width, height and crowning of asphalt layer. (Photo by Matt Miller/KTOO)
Asphalt is scooped up and fed into spreader. (Photo by Matt Miller/KTOO)
Asphalt is scooped up and fed into spreader. (Photo by Matt Miller/KTOO)
Scooping it up, spreading it out. (Photo by Matt Miller/KTOO)
Scooping it up, spreading it out. (Photo by Matt Miller/KTOO)
Even in Southeast Alaska, sunblock is required. (Photo by Matt Miller/KTOO)
Even in Southeast Alaska, sunblock is required. (Photo by Matt Miller/KTOO)
Quality control inspector for the contractor carefully pulls a pre-laid sampling tray after the asphalt spreader passes by. The can of cooking spray is used to make sure the asphalt mix does not bind to the tray. (Photo by Matt Miller/KTOO)
Contractor’s quality control inspector carefully pulls a pre-laid sampling tray after the asphalt spreader passes by. The can of cooking spray (far right bottom) is used to make sure the asphalt mix does not bind to the tray. (Photo by Matt Miller/KTOO)
Asphalt mix is poured into boxes that are carefully marked with the location of the sampling along the highway. They'll be quality tested back at the contractor's office. (Photo by Matt Miller/KTOO)
Asphalt mix is poured into boxes that are carefully marked with the location of the sampling along the highway. They’ll be quality tested back at the contractor’s office.
(Photo by Matt Miller/KTOO)
After sampling, the asphalt mix is smoothed out with rakes. Rollers will soon come by to compact the asphalt aggregate. (Photo by Matt Miller/KTOO)
After sampling, the asphalt mix is smoothed out with rakes. Rollers will soon come by to compact the asphalt aggregate. (Photo by Matt Miller/KTOO)
A rare opportunity for Juneau drivers to legally drive on the wrong side of the road as a spreader slowly makes its way along North Douglas Highway. (Photo by Matt Miller/KTOO)
A rare opportunity for Juneau drivers to legally drive on the wrong side of the road as a spreader slowly makes its way along North Douglas Highway. (Photo by Matt Miller/KTOO)
A roller makes a pass on the freshly laid asphalt mix to compress the aggregate. (Photo by Matt Miller/KTOO)
A roller makes a pass on the freshly laid asphalt mix to compress the aggregate. (Photo by Matt Miller/KTOO)
A quality control inspector for the contractor checks for voids and aggregrate concentration. Optimum aggregate concentration is usually 90 to 95% percent. If the concentration is lower than 90%, then he will usually direct one of the roller crews to make a few more passes in a particular area. (Photo by Matt Miller/KTOO)
A quality control inspector for the contractor checks for voids and aggregrate concentration. Optimum aggregate concentration is usually 90 to 95 percent. If the concentration is lower than 90 percent, then he will usually direct one of the roller crews to make a few more passes in a particular area. (Photo by Matt Miller/KTOO)
The hot asphalt mix releases heat, which distorts light and visuals. (Photo by Matt Miller/KTOO)
The hot asphalt mix releases heat, which distorts light and visuals. (Photo by Matt Miller/KTOO)
An hour after it was laid down, hot asphalt continues releasing heat. (Photo by Matt Miller/KTOO)
An hour after it was laid down, hot asphalt continues releasing heat. (Photo by Matt Miller/KTOO)
Some contractors apply a sealer after the asphalt has been applied and compacted. (Photo by Matt Miller/KTOO)
Some contractors apply a sealer after the asphalt has been applied and compacted. (Photo by Matt Miller/KTOO)
Contractors lay markers on the road center before the painters arrive. That's a quarter to the left. (Photo by Matt Miller/KTOO)
Contractors lay markers on the road center before the painters arrive. That’s a quarter to the left. (Photo by Matt Miller/KTOO)

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