Recycled asphalt pavement as a base and sub-base material

Laboratory and field investigations were conducted to evaluate the use of recycled asphalt pavement (RAP) in roadway base and sub-base applications. The laboratory resilient modulus test results showed RAP has comparable strength with dense graded aggregate base and sub-base material used in the State of New Jersey. Using the spectral-analysis-of-the-surface-waves method (SASW), the field testing program evaluated the elastic modulus of the RAP base in the field and verified the laboratory results. The field test results showed higher modulus and stiffness for RAP than the dense graded aggregate base normally used in state of New Jersey.