Evaluation of healing potential of bituminous binders using a viscoelastic continuum damage approach

A simplified viscoelastic continuum damage model was adopted to analyze experimental data obtained from healing tests consisting of continuous shear loading interrupted by single rest periods. Tests were conducted on various bituminous binders with the purpose of highlighting the aptitude of the proposed methodology in discriminating and ranking their healing potential. Healing was quantitatively assessed by introducing two indicators (HRC and HRS) derived from damage characteristic functions. Results revealed the existence of some irreversible damage after continuous shear loading. In addition, even though polymer modification enhances healing properties of base bitumen, in some cases neat binders may outperform polymer-modified binders.