What challenges prevent the generalized use of recycled asphalt pavement (RAP)?
Using RAP in new construction and rehabilitation of pavements is decades old and continues to be a very popular approach in several countries because of many reasons. However, its use is not wide spread among all regions even in countries with extensive experience with the material. I believe the reason for this is either lack of knowledge on how to manage and use the stockpiled RAP in the most efficient way or improper production and construction of the material when RAP is incorporated. Spreading the knowledge on proper design/usage and efficient technology transfer can increase the likelihood of RAP usage.
Is asphalt concrete made with 100 percent RAP material a viable prospect?
We have been using pure RAP with no virgin aggregate in our laboratory experiments with the goal of characterizing the RAP asphalt binder through innovative non-destructive testing, a major breakthrough with great environmental/economical benefits as the use of solvents in recovering binder is minimized. Designing/preparing asphalt mixes with 100 percent RAP in the laboratory is an easy task but production of 100 RAP in the hot mix asphalt plant and construction of this material at a quality level remains a challenge. Our industry has gained tremendous experience in using high percent RAP in hot/warm asphalt mixes but we are not at a point where we can use it at 100 percent level without sacrificing quality but I believe this is achievable as we move forward.
As a researcher, what is the chief value of presenting your work at an IRF conference?
Presenting results of our research at this event fits very well with the IRF mission of promoting better and safer roads, resulting in social, environmental and economical benefits. One venue towards achieving this mission is through development of new and innovative technological solutions in road material characterization, such as the work presented at this conference. IRF works with so many countries and research presented at a forum provided by IRF has a great impact as it reaches out to a large audience in various parts of the World.