Those grooves make roads last longer
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A: Jamie Holter of the state Department of Transportation says Scott guessed right — the grooves do extend the life of the freeway surface. Here's how: The freeway surface is made of a series of adjacent concrete panels. As years go by and heavy traffic passes over the panels, they move slightly and cracks and gaps develop. The road becomes rough, requiring the concrete panels to be replaced.
The right lane of the freeway is usually the first to show this wear and tear, partly because heavy trucks often use this lane, Holter said.
To extend the life of the freeway, often more than 10 years, adjacent concrete panels are tied together with steel bars. That helps the panels last longer because they are more stable and remain aligned, Holter said. To install the steel bars on older freeways, crews grind grooves into adjacent concrete panels, insert the bars, then cover them with concrete.
"When we build new freeways, or rebuild old ones, we routinely install the steel bars," Holter said.
Q: Ken Kartes says he has lived in the Auburn area since 1985, and travels Highway 18 daily. "I have found the stretch of highway between 167 and the Green River bridge to be the dirtiest road that I have ever traveled," he said. "It seems that the only time the sweepers appear is right before or after any construction."
A: Pat Moylan of the state Department of Transportation says that stretch of Highway 18 has been one of the most difficult to keep clean, at least partly because gravel and logging trucks constantly use that road. Concrete barriers in the median and on the shoulders trap litter, rocks and other material on the very narrow shoulder, and occasionally, in the lanes.
To safely sweep the area, Moylan says maintenance crews must close a lane to traffic and surround the sweeper with safety trucks. To help keep traffic moving, crews usually sweep at night.
But Transportation Department spokesman Stan Suchan says there have been accidents along the highway as a result of motorists attempting to pass maintenance crews, "so motorists need to pay attention and give them some room."
Suchan says maintenance crews will "do our best to keep up with debris in this area and continue to sweep this road several times a year, and before and after all construction work."
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• Roger Sellers of Kent, who regularly commutes to Fort Lewis, says windshields on both his cars have been cracked by rocks on Highway 18 through Auburn and Interstate 5 through Tacoma. "I can't count the number of windshield chips and sand-blasted paint nicks on my cars from this commute," he said. His suggestion: Besides increasing the fleet of road sweepers, the state should consider using rock salt on roads, if needed, instead of sand.
• Rick Lingle of Burien, who says he drove 18-wheelers for 25 years, says the problem with some motorists getting cracked windshields may be that they're following trucks too closely. "I've lived here for many years and I don't have them," he said. "Some people do follow too close."
Bumper note
Officials at Seattle-Tacoma International Airport say a recent study indicates that at least some of the ground-traffic troubles at the airport can be attributed to drivers circling the airport's pickup drive repeatedly while trying to pick up arriving passengers.
"We learned that 40 percent of cars and drivers on the pickup drive are making at least two trips through the airport before picking up their arriving passenger," said Michael Civitelli, manager of airport operations.
During peak periods, cars looping around the drive create backups that affect the ticketing drive, Civitelli said. The departure and pickup lanes merge onto the recirculation ramps, meaning that a backup at baggage claim can slow passengers trying to get to outbound flights.
Civitelli said Port of Seattle officials are looking at a number of long-term solutions for breaking the traffic jam. In the meantime, they've issued some suggestions for drivers:
• Check the airline's Web site to learn the actual arrival time of a flight. There's no point in showing up at the scheduled arrival time if the flight is delayed.
• Plan to arrive at Sea-Tac 30 minutes after the flight's actual arrival time. Officials say it could take that long for a passenger to get off the plane, get out of the concourse to the main terminal and claim luggage.
• Consider parking in the airport garage and meeting an arriving passenger inside, at the baggage-claim area.
Bumper welcomes feedback on topics appearing in this column. E-mail us at bumper@seattletimes.com or call Charles Brown at 206-464-2206.
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