life of asphalt
#1
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life of asphalt
This is part question and part rant
The one lane dead end road I live off of was paved 25 yrs ago. A dozen or so yrs ago they patched a chuck hole, 6 months ago they repaved the last 100' of the road and now last week the county came thru and patched every other bad spot
I know the gov't never has enough money and read in the paper that they claim they only have enough funding to repave the roads every 45 yrs .... although the 2 lane road our road connects to has been repaved 3 times since 1992. Anyone know how long an asphalt road is supposed to last between pavings?
OK, probably more rant than question
The one lane dead end road I live off of was paved 25 yrs ago. A dozen or so yrs ago they patched a chuck hole, 6 months ago they repaved the last 100' of the road and now last week the county came thru and patched every other bad spot
I know the gov't never has enough money and read in the paper that they claim they only have enough funding to repave the roads every 45 yrs .... although the 2 lane road our road connects to has been repaved 3 times since 1992. Anyone know how long an asphalt road is supposed to last between pavings?
OK, probably more rant than question
#2
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My understanding is it's based a lot on the weight of the vehicles using it. Barring anything heavy, they can last decades. Drive a semi on it once in a while and the lifespan plummets quickly.
#3
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25 yrs = 2.5 decades
A garbage truck is probably the heaviest vehicle that travels the road on a regular basis, maybe a dump truck 1-2 times a year. There are 11 houses/trailers on the road [1 house has been vacant for yrs] so not a lot of car traffic but even so I bet it wouldn't take a lot of effort with my tractor to tear up the pavement as it's crumbling in quite a few areas that they didn't patch.
A garbage truck is probably the heaviest vehicle that travels the road on a regular basis, maybe a dump truck 1-2 times a year. There are 11 houses/trailers on the road [1 house has been vacant for yrs] so not a lot of car traffic but even so I bet it wouldn't take a lot of effort with my tractor to tear up the pavement as it's crumbling in quite a few areas that they didn't patch.
#4
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I really know nothing about paving roads but my opinion is that it depends more on the substrate, the ground under the asphalt, than the asphalt itself. If the substrate is absolutely solid then the asphalt should last a very long time. If the substrate is soft or shifting dirt the asphalt won't last very long at all.
Many decades ago Seattle used what I thought was a good system. They would pave the street with about six to ten inches of reinforced concrete and then add about four inches of asphalt. The concrete provided the strong substrate but was hard to patch so the asphalt, which is easy to patch, provided a "wear layer" protecting the concrete. Of course this was a rather expensive method and is no longer in use.
When they added carpool lanes to the freeways they simply compacted the dirt and laid several inches of asphalt. These lanes are not lasting all that well.
Many decades ago Seattle used what I thought was a good system. They would pave the street with about six to ten inches of reinforced concrete and then add about four inches of asphalt. The concrete provided the strong substrate but was hard to patch so the asphalt, which is easy to patch, provided a "wear layer" protecting the concrete. Of course this was a rather expensive method and is no longer in use.
When they added carpool lanes to the freeways they simply compacted the dirt and laid several inches of asphalt. These lanes are not lasting all that well.
#5
This.
And how or what purpose the road was designed for. For residential use a dump truck, overloaded, twice a year could accelerate it's demise.
depends more on the substrate, the ground under the asphalt, than the asphalt itself. If the substrate is absolutely solid then the asphalt should last a very long time. If the substrate is soft or shifting dirt the asphalt won't last very long at all.
#6
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While I don't know what the base under the road consists of, my property is predominately slate rock which is often used around here as a base for driveways. The road was gravel chip and seal when I bought the place in early '91 but was paved shortly after [but before I moved here]
For those of you in residential neighborhoods - how often do they repave?
For those of you in residential neighborhoods - how often do they repave?
#7
For those of you in residential neighborhoods - how often do they repave?
#8
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In my old neighborhood the city would "seal coat" the streets about every five years. This consisted of laying a coat of liquid asphalt and then dropping either crushed rock or pea gravel into the asphalt and then rolling it. We would have clouds of dust for a few days and then a somewhat rougher than average asphalt road for a few weeks until everything settled. They stated this would prolong the life of the road and reduce the need for total repaving. I've lived in my current house for sixteen years and I have never seen any "seal coating" of the streets in the area although the city newsletter will sometimes mention an area to be seal coated.
When I was a kid in Seattle they brought in a machine that ground up the top-most layer of asphalt and then a second machine that had umpteen propane burners under it softened the remaining asphalt while a standard asphalt-laying rig added new asphalt and that was followed by a roller to compact the new to the old. Did a great job of rebuilding the wear layer of the streets. I only saw that type of operation that one time but for several years I have seen machines that grind/chew off the upper layers of asphalt, sometimes down to the concrete substrate, and then they lay new asphalt. I've also seen big chunks of new asphalt break out when using this technique.
When I was a kid in Seattle they brought in a machine that ground up the top-most layer of asphalt and then a second machine that had umpteen propane burners under it softened the remaining asphalt while a standard asphalt-laying rig added new asphalt and that was followed by a roller to compact the new to the old. Did a great job of rebuilding the wear layer of the streets. I only saw that type of operation that one time but for several years I have seen machines that grind/chew off the upper layers of asphalt, sometimes down to the concrete substrate, and then they lay new asphalt. I've also seen big chunks of new asphalt break out when using this technique.
#9
"seal coat" the streets about every five years. This consisted of laying a coat of liquid asphalt and then dropping either crushed rock or pea gravel into the asphalt and then rolling it.
#10
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I don't think I've seen them oil and spread chat on a road since the 60's but I remember it being a common occurrence, not sure why they stopped. It is common procedure in the south for them to chew up the top layer of asphalt prior to laying new. I assume the chewed up asphalt gets recycled into a new batch.
Didn't realize that other neighborhoods had their roads just as neglected. I thought most of it had to do with our corrupt hwy dept although we voted in a new hwy commissioner last year so there is hope things will get better.
Didn't realize that other neighborhoods had their roads just as neglected. I thought most of it had to do with our corrupt hwy dept although we voted in a new hwy commissioner last year so there is hope things will get better.
#11
The road leading to our drive is paved once a century, I believe They do the tar/pebble thingy every so often when we complain enough.
Georgia DOT has a few machines similar to what you mention. They eat up the pavement, reconstitute it in a chamber mixing it with whatever is appropriate, then the same machine lays out a road behind it that only needs compressing. Quite an impressive machine to say the least.
they brought in a machine
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Again, when I was a kid there were a few dirt roads in our neighborhood that were periodically "oiled". This was NOT the same as seal coating as it was actually a hot oil that was sprayed over the dirt. The old man that lived across the street used to drive a road oil rig until it caught fire while he was filling it. He had to jump off and hurt his back in the process. That crap was more like residual (bunker) fuel oil than anything else I could describe. Of course environmental reasons prevent the use of oil on roads these days.
#13
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I assume the 'oil' that was spread on the paved road followed by a thin layer of chat or stone dust was a type of coal oil sealer. I also remember the dirt roads that were oiled to cut down on the dust. I always thought it was used oil mixed with whatever was handy .... not that I ever knew for sure
#14
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Sealer and chip rock is still used a lot where I live. My dad has lived in the same house for 35 years now and I've seen that done at least three times on his street.
#15
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I developed an almost unhealthy fascination with paving technologies when I worked for a state DOT. I still love the smell of hot asphalt. That can't be healthy, can it? I can tell you, there are so many different technologies and techniques out there -- and like so much else, it comes down to time and money. I've seen new roads last for years, and I've seen them crumble in months.
I've still seen "fresh oil" signs in use around the country where dirt roads are "oiled," but they're almost never really petroleum oil products. Maybe agricultural oil products, usually other kinds of binders or agents, like resins, acrylics, or even mag or calcium chloride. Those are the same liquids that are used in ice removal or road salt prewetting, since they draw moisture from the air. It helps keep moisture in the dirt and reduce dust.
Like others said, chip-sealing, or seal-coating, is still common practice in some parts. It's not terrible for replacing a wear layer. But substrate is so important, as is maintenance. Where I live now, the DOT is great about hot tar or mastic-sealing cracks. Happy squiggles all over the road. But it prevents water infiltration and damage from freeze-thaw cycles. Cross the border, and the DOT apparently doesn't know what repaving or maintenance is. They just let it crumble, then tamp in some cold patch. If it lasts a year, it's a surprise.
I've still seen "fresh oil" signs in use around the country where dirt roads are "oiled," but they're almost never really petroleum oil products. Maybe agricultural oil products, usually other kinds of binders or agents, like resins, acrylics, or even mag or calcium chloride. Those are the same liquids that are used in ice removal or road salt prewetting, since they draw moisture from the air. It helps keep moisture in the dirt and reduce dust.
Like others said, chip-sealing, or seal-coating, is still common practice in some parts. It's not terrible for replacing a wear layer. But substrate is so important, as is maintenance. Where I live now, the DOT is great about hot tar or mastic-sealing cracks. Happy squiggles all over the road. But it prevents water infiltration and damage from freeze-thaw cycles. Cross the border, and the DOT apparently doesn't know what repaving or maintenance is. They just let it crumble, then tamp in some cold patch. If it lasts a year, it's a surprise.