The rheological behavior of recycled asphalt binders is important in the design of the optimum content of reclaimed asphalt pavement (RAP) material to be used in highway recycling projects. In this study, oscillatory tests were performed on recycled binders of varying RAP concentrations. The complex modulus master curves were constructed using the time–temperature superposition principle. The zero shear viscosities (ZSVs) were estimated using the Carreau–Yasuda model on the complex viscosity master curves for all the recycled binder combinations. It was found that the activation energy of flow changed linearly from 115.1 to $185.8\mathrm{kJ}/\mathrm{mol}$ with an increase in the RAP content, whereas ZSV varied exponentially with an increase in the RAP content. A good correlation was found between the ZSV and the Superpave rutting parameter ($G^{*}/\sin \delta$ ). An equation was derived to predict the $G^{*}/\sin \delta$ at any RAP concentration and temperature. For practical use, a $G^{*}/\sin \delta$ contour plot approach is introduced to calculate directly the maximum and minimum RAP content for any target binder grade suitable for the construction site. cA noticeable change in rheological behavior of recycled binders was observed on either side of the 40% RAP incorporation level.

Precise travel time prediction allows travelers and system controllers to be aware of the future conditions on roadways and helps in pre-trip planning and traffic control strategy formulation to lessen the travel time and mitigate traffic congestion problems. This research investigates the possibility of using the GPS trajectory dataset for travel time prediction in Indian traffic conditions having heterogeneous disordered traffic and improvement in prediction accuracy by shifting from the traditional historical average method to modern machine learning algorithms such as linear regressions, decision tree, random forest, and gradient boosting regression. The present study uses massive location data consisting of historical trajectories that were collected by installing GPS devices on the probe vehicles. A 3.6 km long stretch of the Delhi–Noida Direct (DND) flyway is selected as a case study to predict the travel time and compare the performance as well as the efficiency of various travel time prediction algorithms.

The utilization of recycled asphalt pavement in the construction and maintenance of flexible pavement with asphalt emulsion is advantageous and environmentally friendly. It saves energy due to zero heat loss during the mixing and laying of pavement compared to hot mix asphalt. Recycled asphalt pavement (RAP) is a sustainable material in place of virgin aggregates in road construction. The focus of this study is (i) virgin aggregate production, (ii) the utilization of waste material (additive), (iii) reducing the production temperature, and (iv) recycled RAP material in the pavement. This paper attempts to create a venue for using RAP greater than 50% during pavement construction. Cold mix asphalt (CMA) containing 0%, 50%, and 100% RAP materials with different dosages of cement, fly ash, and Stabil-road at 1%, 2%, and 3% of dry aggregate weight were used for ascertaining the mechanical and volumetric properties of mixtures. The mechanical properties for CMA samples, such as stability, tensile strength, moisture susceptibility, stiffness modulus, and the abrasion loss of CMA samples, were evaluated with and without RAP incorporation. Present laboratory studies revealed that a cold mix containing 50% RAP materials produced a higher stability value than the control mix, irrespective of the types of additives in its contents. All the additives can potentially resist moisture damage in the mix. Also, a significant improvement in the resilient modulus was considered for RAP-incorporated mixtures with the additives.