Chicago Green Pavement

Well done Chicago City Hall! And if you are interested I have another green idea that might interest you. That way, you could turn the Old Song (from Calamity Jane) into "I just blew in from our Green City. Oh! Chicago City is mighty pretty! Etc. Etc"

Rumo(u)r has it that recycled plastic railway/railroad ties/sleepers are also in use there.

Good, innit?

Update: PA has been using both products in their asphalt and concrete mixes for the past 30yrs. Our company alone has sold over 250,000 tons of asphalt with 45% RAP, plus recycled bag house fines, while burning WDLF to the city of Philadelphia this year. Never mine the numerous other municipalities throughout the greater Delaware and Lehigh Valleys that have been recieving it. It's about time Chicago caught up to the times

hmm That real intresting. There has been a company in Bowling Green, KY that has been doing that for about 10 years.

....and Chicken Shed, NV.

Congratulations Chicago! The next step is to incorporate RAP material in other pavement layers.

Do you know that in Europe there're some studies that found that the use of cold stabilized RAP material in base layers can strengthen all the pavements structures?!

Go ahead, let's try some new and better green pavements.

best wishes

That's a very common practice here in Pennsylvania to use RAP as a sub-base for asphalt pavements. Same thing with crushed concrete. It seems Chicago and Europe need to catch-up a little..

That's true, although no one can really tell the environmental effects of using "only" RAP in subbase layers.

What I was trying to say is that there're Recent studies that prove that the correct stabilization of RAP, with emulsion or cement can constitute a very good subbase layer, with very good and satisfactory elasticity modulus. You only have to study the correct formula.

Congratulations for Pensilvania too...and, let's try some new solutions!

We have been try a technique called rol-u-mack (not sure of the spelling), which basically is a milling machine milling up the road conveys it to a mixer with asphalt lays it back down then rolls it it again. Several problems occur because PA has a high freeze/thaw factor this would brake up rather quickly if it used as a pavement surface plus the ride ability is really poor. If used as a sub-base if is very expense because of the addition of asphalt to it. We usually try and keep asphalt and concrete away from each other because they usually do not stick together and you end up with pop outs causes potholes.

The correct use of RAP material and cement can constitute a high quality subbase pavement. I can assure it to you. I've made some lab and in field experiences with very good results. The results were so good that it's possible to reduce asphalt layers.

Althought I agree that cement anf bitumen must stay way from eachother, RAP material has always very hard bitumen, (10/20) that soffered several changes since they were inicialy aplied in new pavements. So if I can get a cold mix of RAP, cement and a virgin agregate I can make a good base layer that provides better pavements.

Besides it's a very low cost solution that can provide a new use of waste material such as RAP, avoidind the need to spend energy heating this material and mixing it with another hot asphalt mix. It's common to use hot recycling techniques allover the world.