And then there's the bone-
(Edited July 13: added info on co. that did GV work.)
The work was done by Intermountain Slurry Seal, whose Calif. area manager said, basically, that the work was done to preserve the road, but not to improve the ride quality, unlike an asphalt overlay. The industry term for what was done is "Pavement Preservation treatment": "the City selected [a] two part system. The first application was a asphalt rubber chip seal that contains up to 20% recycled tires. The second part was a Caltrans slurry seal application."
(see letter appended to this post for more.)
As for why the ride would be worse now than pre-treatment, the response was:
"As far as the road being bumpy now with this treatment, what was there is still there. Our aggregate that is used for the final coat is 1 \4 minus material. "Hmm. Still a mystery then?
(Anyone want to take it up? or offer your perceptions of road quality now vs. formerly? )
Related: an interesting story in The Union today, Kyle Magin's Bid dispute disrupts Tinloy Street bus station project , showing what happens when federal construction monies intersect with "buy local" preferences.
Full email from Steve Olsen, California Area Manager of Intermountain Slurry Seal, regarding the 'resurfacing' of Idaho-Maryland Road to Sutton to Dorsey:
(Ctrl+ to enlarge, Ctrl- to shrink again)
To start with, the treatment that was selected for this road is a proven Pavement Preservation treatment not what industry would refer to as a resurfacing project as you stated. These Pavement Preservation treatments do not improve the ride quality. This in comparison to what a asphalt overlay or full blown rehabilitation will provide. The treatment that the City selected is two part system. The first application was a asphalt rubber chip seal that contains up to 20% recycled tires. The second part was a Caltrans slurry seal application. These treatments are commonly called Cape Seals. These treatments are selected for various reasons. The best time for selection is when the Pavement is in very good condition. But in these tough economic times that is not always the case. These Pavement strategies are very simple in terms of the economic value. For for every dollar spent on Preservation this can save up to 10 dollars by delaying costly rehabilitation costs. These treatment cover so much more Square Footage for the dollar in comparison to the costs for overlays and rehabilitations. I'm not positive but the City may have also applied and received a rebate grant from the California Waste Management board for the use of the asphalt rubber chip seal.
At the end of the day these Pavement Preservation strategies have a proven history of providing seal protection for the existing asphalt surface combined with the short and long term costs savings. These treatment do not provide much improved rideablity that more expensive treatments can provide. Just keep in the back of your mind that again these treatments are never selected where the ride quality is a prerequisite for the finished job or where pavement profiling takes place to measure the improved ride qualities.
Hope this helps.
Respectfully,
Steve Olsen.
Second (July 13) email:
These treatments provide added skid resistance value over traditional pavements. So the ride quality could appear to have rough ride. Example- Co- Efficient skid numbers for asphalt come in the low 30's. Cape seals can enter the high 50's. The lower the number the smoother the surface and vice versus. You get a rougher surface with higher skid numbers. As far as the road being bumpy now with this treatment. What was there is still there. Our aggregate that is used for the final coat is 1 \4 minus material. Very small.
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