| dc.description.abstract | Asphalt is one of the most common materials in pavement construction in the world. The United States has more than 4.3 million kilometers of roads and highways, with 94 percent of those being flexible pavement according to the National Asphalt Pavement Association. Moreover, the asphalt mixture is a complex material which is a blend of asphalt binder, aggregate, and air voids. The properties of these components have a major impact on the overall performance of the asphalt mixture. Furthermore, asphalt concrete pavement is affected by traffic loading, temperature, moisture, and aging. Pavement deteriorates under the abovementioned conditions; for example, cracking, raveling, and potholes can develop impacting pavement serviceability. Past studies have demonstrated that various asphalt mixtures have the ability to heal with time. Healing can counteract deterioration on asphalt pavements performance. Numerous researchers have proposed several models for predicting healing of microdamage in different materials. However, most of those models were developed to predict the responses under specific states, and consequently, usually do not represent the behavior of material accurately. The main purpose of this research is to study the influence of microdamage healing on stress intensity factor (SIF), displacement, and stress fields near a crack tip in the materials that have the ability to heal. The microdamage healing model that is used in this study considers the effects of both instantaneous healing and time-dependent bonding strength. The results indicate that an increase in the value of bonding strength and the length of the healing process zone lead to a reduction in both stress and displacement fields near the crack tip. | en |
