is tarmac recycled

[matty2670]

what happens to old tarmac when it's dug up? Is it recycled or does something else happen to it?

[Clanad]

At least here in the U.S., old pavement is recycled by grinding it through a huge machine and using it for either fill in new roads or heated, melted and re-mixed into what we call asphalt...

[matty2670]

Thanks Clanad. A work colleague brought this up recently and it's been bugging us ever since!

[sddsddean]

I do a lot of road planing (big machine takes up to 250mm of tarmac off the road and it goes into the back of our trucks). The vast majority of it we sell to farmers and anyone else who wants to make up their muddy tracks and yards. If you put it down right it will go down like rock. In this respect it is recycled. We do sometimes take it to the local tarmac plant where it is re-used. It cannot be used for the top coat (wearing course), but can be used in base course and road base (up to about 25% I think). The main company that make road planers is a German firm called Wirtgen and they have brought out a machine that you hook up a bitumen tanker and a cement tanker to and it recycles the planings directly into base course. I haven't seen one and as far as I know there isn't one in the UK, but its a large investment as they cost about �1million each.

[sddsddean]

Heres a planer at work
http://www.american-material-handling.com/Road Tec/ColdPlaner.jpg

[Panic Button]

Some of the bridleways near us which were an absolute quagmire, have now been made useable by minced up old roadway being dumped there.

In amongst the rubble are old cats eyes, surprisingly large lumps of iron. I'm surprised the planing machine can cope with them.

With the price of metal these days I'm surpirised they didn't pick them out.

[sddsddean]

Thats unusal PB. Usually a couple of blokes go along breaking out the cats eyes in front of the planer. As you say, people don't realise how big the frames are. The planer has no problem with the more modern plastic stick on studs. Also it always surprises me that they dont remove the square silver studs at pedestrian crossings, as they have a 4" long spike on them sticking them into the tarmac.