Cracking Asphalt

[chessie4905]

 I notice here many roads are getting  crosswise cracking asphalt after a few years of applying. You feel it at every joint, maybe 50 feet apart. Used to be this commonly happened front paving over former concrete roads. But these roads were never concrete. I wonder if during the last crude oil price spike, that they started to reduce the amount of tar to stone mix used. It would make road surface more durable, but less able to deal with contraction. Just wondering.

[richard5933]

Same here in cheese country. Our county highway was repaved with new asphalt only ten years ago, and now it's nothing but a series of wide cracks across the road bed every 10-20 yards. Can't blame the concrete underneath, as there is none. They did a grind-in-place repave, where they grind the old asphalt in place and then run compactors over it to create a new base level. My guess is that the water table is still too high and/or the ditches are too shallow and the snow melt and rain end up under the road bed, which in turn causes cracking in the winter freezes. Can't blame road salt really, because since the downturn in 2008 they've cut back drastically on the amount of salt used.

[lvmci]

Hi All, I travel to Flagstaff frequently from Las Vegas, by US93 (soon to be I -11 ) and I-40 and has heavy ttraffic. The old US93 from Boulder Dam to Kingman AZ is some of the oldest pavement around and it was done in short sections, 10 to 15 foot perpendicular sections. Kinda like how concrete is poured. And all of those sections are potato chipping, like old roof shingles, all at the same time, this is besides the heavy traffic corrosion. I noticed they redid the worst section in the more countiuous flow style, for the start of I- 11 on the AZ side of the Dam. Hopefully that will not break down in short sections, lvmci...

[PP]

I read an article a while back that they're constantly experimenting with different asphalt mixtures trying to come up with something durable and cheap. We have a road near us that caused the Mini we used to tow to literally fall apart because the wheels were so small they fell into the expansion cracks. Not good!

[lostagain]

Various levels of government collect billions $ in fuel taxes. There is no excuse for bad roads.

JV

[luvrbus]

They started years back using more bunker C than asphalt in roads it cut out 1 more step in refining and plus the EPA thought bunker C was better for the environment when it came to run off water. They needed a place to go with the bunker C since the railroads and shipping stop using it so now your roads get it 

[TomC]

My last year of trucking was 2,000. That year Texas was repaving a section of I-10 east of El Paso. The method?-First lay down a thick layer of Asphalt, then over that fully reinforced continuous pour concrete. I recently drove that section and was impressed that 18 years later the concrete was still very smooth. Obviously Texas has down pat the method by which to totally repave a highway and for a projected 50 year life. Good Luck, TomC

[chessie4905]

In Pa. at Water Street, they poured concrete, and then paved on top of it . Has held up well. A section out near Allentown was paved with 14 inches of concrete with diangle joints.

[eagle19952]

Obviously Texas has down pat the method by which to totally repave a highway and for a projected 50 year life.

Obviously, the subsurface there is stable.
Has as much to do with it than the mixture.
Funding has a lot to do with it too, but I won't go there.

[richard5933]

In Pa. at Water Street, they poured concrete, and then paved on top of it . Has held up well. A section out near Allentown was paved with 14 inches of concrete with diangle joints.

They've tried something similar around here, only with less-than-stellar results. When the concrete surface gets beyond repair, they grind it down about an inch till they hit solid material. Then they lay asphalt over the old concrete. All is good until the next winter when the concrete underneath begins to move and cracks the asphalt. Then water gets in from the melting snow, refreezes, and bye-bye asphalt.

It truly is all about the base. And the salt. And the sub-zero temps that will heave and crack an otherwise great stretch of asphalt.

[luvrbus]

It's about about the plasticity of soil,you need to treat a high plasticity soil with lime or fly ash to lower the PI Texas is good about spending the money to treat a sub base.Same with a building I have had to under cut slabs for WalMart to some times 4 ft below finished floor grade then haul in select material with a low plasticity (PI) or mix the existing removed dirt treat it with lime and bring it back to sub level in 8 inches lifts very costly but the buildings never heaved or the floor cracked.You can read about plasticity if it's to high the water will not pass through it and when it freezes there goes your payment or building       

[6805eagleguy]

I just drive an eagle so I don't feel the expansion joints!
No offense to the non-eagle guys!

[chessie4905]

I call b.s. on that.

[Dave5Cs]

He said that on PORPOISE.....

[DoubleEagle]

We porpoise over the cracks on purpose.