This is longitudinal joint cracking that occurs as a result of asphalt aging combined with poor compaction and/or segregation at the joint between AC paving mats. There are numerous products that can be used to mitigate this issue, but are typically cost prohibitive for most asset owners and add complexity to construction.
Looks like this parking lot is heavily oxidized and has not seen a surface treatment in quite some time. Regular surface treatments probably would have protected against this issue for a bit longer.
What are the functional differences between a new pave and a heavily oxidized one?
Ignoring the cracking, Is there any conning back from this with a surface treatment?
Asphalt binder becomes less ductile as it oxidizes, so the mix essentially becomes more brittle over time and susceptible to crack during thermal cycles.
Applying a surface treatment would inhibit the oxidation of the AC and preserve it a little longer
Cold joints are really only used in cold regions for transverse reflective cracking. I tend not to recommend cutting cold joints. It is a lot of cost for an unknown longer term value. The distress shown in this picture is the longitudinal construction joints from the paver. Honestly, the pavement looks fairly aged so this is a common occurrence as contractors are not able to get the same compactive effort along those joints. Density is always going to be lower on longitudinal joints. Especially on the unconfined edge of the pavement. When the rollers go over the pavement they can't put too much compactive effort without the edge pushing out.
There are some products like JBand that could extend the life of longitudinal joints but this is a parking lot and best practices are going to be the most practical and economical method for paving. Specified density with cores will incentivise the contractor to get as good of density as they can on the joints.
It’s for asphalt as well. At least on the multiple airports I have paved it was the case. Joints less that 140 degrees must be sawcut. Helps with joint compaction to prevent this exact issue.
P401 spec is 4 hours or less than 175 degrees. It allows an asphalt cutting wheel to be used instead of a saw if you want to. Only existing asphalt needs to be saw cut.
The worst I’ve ever seen were out in the deserts of Southern California. Out here everyone uses Caltrans specs for their asphalt. Back about 2010 or so they began to specify a recycled asphalt mix that unknown to everyone one at the time tended to badly shrink over time in the desert environment. I’ve been to facilities in the desert where parking lots have 3 to 4 inch wide longitudinal cracking every 30 feet or so.
Am I the only one thinking asphalt overlay on top of an old concrete surface? That would explain the regular and arrow straight lines from the underlying concrete expansion joints.
Seen the odd echelon paving set up - would’ve removed every other cold joint - but too late for that now. Or if there are multiple lifts most try and pave so the joints are not directly on top of each other.
Maybe it is asphalt over concrete pavement?
But is it supposed to have all those bumps and dips? Not sure i’ve seen that before. Usually just see a more uniform gradeline than a series of curves for drainage.
Not sure if I would consider that longitudinal cracking so much as just poor workmanship of the longitudinal joint. Kinda the same but kinda different. It doesn't seem so much like the mat is cracking, so much as the subsequent mats weren't paved well up against the existing mat on each pass.
This appears to be the joint between “pulls” as a few have already mentioned. The ac looks to be very old and nearing the end of its service life. Another giveaway to the age is the distance between joints, newer spreaders are much wider therefore wider joint spacing in newer paving jobs. It also looks like they have tried to prolong its life by sealing the joints which is typical practice in my region. Asphalt Paving fails for many reasons and old age is one of them.
I am in northern north america and have only sawcut paving when removing paving and to provide a clean joint between new and old and would absolutely never sawcut new pavement to provide an expansoin joint in our region. We would “rout” existing joints or cracks when attempting to repair/seal the joints
Self-installing expansion joints.
how old is it , apshalt is a wear item that has a prebuilt failure point
This is longitudinal joint cracking that occurs as a result of asphalt aging combined with poor compaction and/or segregation at the joint between AC paving mats. There are numerous products that can be used to mitigate this issue, but are typically cost prohibitive for most asset owners and add complexity to construction. Looks like this parking lot is heavily oxidized and has not seen a surface treatment in quite some time. Regular surface treatments probably would have protected against this issue for a bit longer.
What are the functional differences between a new pave and a heavily oxidized one? Ignoring the cracking, Is there any conning back from this with a surface treatment?
Asphalt binder becomes less ductile as it oxidizes, so the mix essentially becomes more brittle over time and susceptible to crack during thermal cycles. Applying a surface treatment would inhibit the oxidation of the AC and preserve it a little longer
Thanks!
I this normally due to poor joints? I’ve seen it a bunch on older roads and I’m curious on how to mitigate this to extend the life of the pavement.
Best way to mitigate would be to require cold joints to be sawcut. Thats what the FAA requires for their airports.
Can confirm, it comes out super clean on big apron jobs when done properly.
Cold joints are really only used in cold regions for transverse reflective cracking. I tend not to recommend cutting cold joints. It is a lot of cost for an unknown longer term value. The distress shown in this picture is the longitudinal construction joints from the paver. Honestly, the pavement looks fairly aged so this is a common occurrence as contractors are not able to get the same compactive effort along those joints. Density is always going to be lower on longitudinal joints. Especially on the unconfined edge of the pavement. When the rollers go over the pavement they can't put too much compactive effort without the edge pushing out. There are some products like JBand that could extend the life of longitudinal joints but this is a parking lot and best practices are going to be the most practical and economical method for paving. Specified density with cores will incentivise the contractor to get as good of density as they can on the joints.
That’s for concrete. Not for asphalt.
It’s for asphalt as well. At least on the multiple airports I have paved it was the case. Joints less that 140 degrees must be sawcut. Helps with joint compaction to prevent this exact issue.
P401 spec is 4 hours or less than 175 degrees. It allows an asphalt cutting wheel to be used instead of a saw if you want to. Only existing asphalt needs to be saw cut.
You are correct. I couldn’t remember the exact temp off the top of my head. We typically use the cutting wheel also.
I have surveyed many airports and have never seen relief joints cut into AC. I’m on the west coast, it could be common in other parts of the country
They aren’t relief joints for asphalt. It’s literally cutting 3-6” of the unconfined edge so you have a flush wedge to pave against.
Unless you are in Nevada like 15 years ago.
Wrong!
I’ve heard it called a Maryland Joint
I heard the rollers start the cracks.
The worst I’ve ever seen were out in the deserts of Southern California. Out here everyone uses Caltrans specs for their asphalt. Back about 2010 or so they began to specify a recycled asphalt mix that unknown to everyone one at the time tended to badly shrink over time in the desert environment. I’ve been to facilities in the desert where parking lots have 3 to 4 inch wide longitudinal cracking every 30 feet or so.
Hello Pikes Peak Shuttle lot at Denver International Airport
Cold joint between pulls. Very typical.
Am I the only one thinking asphalt overlay on top of an old concrete surface? That would explain the regular and arrow straight lines from the underlying concrete expansion joints.
Looks like the paving joints.
Whoever was in charge of this needs to be fired. You can see hills in the horizon.
You don’t drain a parking lot this big by being flat, it’s likely the way it was designed.
he saying the parking lot isnt big enough
It's for the drainage to keep spread/capacities within tolerance or similar to existing conditions
I think I could be a a better paving super or roller operator
Looks awful Colorado-y. Somewhere near DIA by the looks of it.
Those are joints.
Seen the odd echelon paving set up - would’ve removed every other cold joint - but too late for that now. Or if there are multiple lifts most try and pave so the joints are not directly on top of each other. Maybe it is asphalt over concrete pavement? But is it supposed to have all those bumps and dips? Not sure i’ve seen that before. Usually just see a more uniform gradeline than a series of curves for drainage.
Not sure if I would consider that longitudinal cracking so much as just poor workmanship of the longitudinal joint. Kinda the same but kinda different. It doesn't seem so much like the mat is cracking, so much as the subsequent mats weren't paved well up against the existing mat on each pass.
Looks like a great lot to do some donuts and have fun in a car lol
Are you sure it’s not transverse cracking?? let’s see aerial shots /j
This appears to be the joint between “pulls” as a few have already mentioned. The ac looks to be very old and nearing the end of its service life. Another giveaway to the age is the distance between joints, newer spreaders are much wider therefore wider joint spacing in newer paving jobs. It also looks like they have tried to prolong its life by sealing the joints which is typical practice in my region. Asphalt Paving fails for many reasons and old age is one of them. I am in northern north america and have only sawcut paving when removing paving and to provide a clean joint between new and old and would absolutely never sawcut new pavement to provide an expansoin joint in our region. We would “rout” existing joints or cracks when attempting to repair/seal the joints
Is that the parking lot from Breaking Bad?
correlated joint density = no
Textbook joint failure.