Evaluation of high performance noise-reducing asphalt layers using accelerated pavement testing

An optimal wearing course should provide safety, comfort, and durability while minimizing the impact on the environment. Some of those functions are antinomic and thus difficult to integrate considering the current state of the art. A large experimental program was carried out, involving the evaluation of 10 asphalt mix designs. Two innovative acoustic mixes, plus a traditional one, were selected from this program. Lab experiments demonstrated that the grading curves and void structure of these new mixes lead to a good compromise between acoustic performance, skid resistance, durability, and rolling resistance. A full-scale experiment was then carried out on an accelerated pavement testing facility, to validate the good behavior highlighted by laboratory studies embodied by the enhancement of acoustic absorption (peak values of 0.86 and 0.78 for the two innovative acoustic mixes, 0.39 for the reference mix) for equivalent mechanical properties. After the experiment, the properties of the test sections (mechanical properties, surface roughness, skid resistance, and acoustic properties) were evaluated. The results confirmed the good durability of the mixes under traffic loading.