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I looking for technics for rolling out hot & cold seams. We sometimes run into trouble with seams that are very noticable after compaction.
It all starts with your crew. the screed man has to have the right thickness and the lute man has to push off the right amount of material. jump on the seam as soon as you can,and pinch about 2″ of the hot material and then go to 4″ and then about a half a drum. and so on. and the weather makes a big difference. a cold seam will always show more than a hot seam. and a good rollerman can make you look good!!
targuy is right if the hot and cold mat are even but if the joint is in an invert or onthe crown of the road its a little differant. inverts are very hard to roll without leaving roller marks. start by pinching just 2 inchs or less then move to the hot mat androll with the edge of the rollerin the center of the invert. this is not real easy so go slow. weve found if your roller operator is making alot of marks its sometimes easier to run your platetamper perpindicular across the joint while its hot this will remove most of them. a joint in the crown of the road is easy as long as your screed man doesnt have his head up his ass. we always run the center of the drum rihgt on the crown this puts the most weight on the joint. we never vibrate the crown as it will smash the aggragate and turn the joint white. the inspectors in pa frown on that. i hope this helps you out. the best way to learn this is like everything else, try differant techniches and do what works best for you with the conditions your in [roller type, weather,etc] good luck
We always carry a torch for hot on cold joint matching. Keep the heat on the joint just ahead of the roller.
Ahh well you aint gonna make a seam look amazing unless you hit it hot. We were running into this issue because we were doing alot of in city highway work, like 40-50 foot wide roads and 20 foot screeds, what we did was run 3 pavers side by side staggered by only 15 feet or so and that way we got all the seams really hot.
In smaller subdivisions, parking lots etc, you just have unload a few trucks then lift up and go back and keep that seam hot even if you have to leave joints.. Tell your roller man to stay about 6-7 inches away from the side and join em hot.
As for rolling if its hot i’ll go 6 to 9 inches in and pinch it then 3/4 drum on the way back on that pass , if its cold 2 flat mats, ill pinch that 2-3 inches in, I wouldnt reccomend leaving a cold seam in a parabolic road on the crown.
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