Unlike conventional pavements with a service life of 20~30 years, perpetual pavements (PPs) are designed to have a 50-year service life without requiring major maintenance and rehabilitation (M&R) activities. In this way, PPs are more cost-effective than conventional rigid pavements (CRPs) and conventional flexible pavements (CFPs). Nonetheless, even though the economic and mechanical aspects of PPs have been widely studied and well documented, the literature is limited regarding the environmental assessment of PPs. Consequently, this research estimated the environmental burden associated with five pavement structures (one CRP, one CFP, and three PP structures) through the life-cycle assessment (LCA) methodology. Notably, the PaLATE computational tool was used to carry out the LCAs. The results indicated that for CFP, most of the environmental impacts are generated by the M&R activities. Otherwise, for CRP and PP structures, the most impact occurred during the initial construction stage. The study results also revealed that materials production is the sub-stage that most contributed to the generation of environmental detriments. Overall, this comparative case study concluded that the pavement alternative with the slightest environmental damage is the PP structure.

Due to economical reasons and the need for environmental conservatism, there has been an increasing shift towards the use of reclaimed asphalt pavement (RAP) materials in the pavement construction industry. This is a relatively new concept in Colombia with scarce local documented literature, particularly on the mechanical properties of the hot mix asphalt (HMA) mixtures modified by addition of RAP and the corresponding mixture design procedures. This research focused on evaluating the effects of partial- and total-replacements of aggregates by RAP on the mechanical response of dense-graded HMA mixtures. Corresponding results suggest that the highest indirect tensile strength and resilient modulus values in both dry- and wet-condition were obtained for the HMA mixtures produced with 100% replacement of granular material by RAP

Warm-mix asphalt (WMA) technology and recycling of asphalt pavement, i.e., reclaimed asphalt pavement (RAP), have been becoming more popular in recent years due to their economic and environmental benefits. Similarly, bio-oil rejuvenators seem to be a viable solution when the usage of high percentages of RAP is desired. However, employing a high percentage of RAP in WMA using bio-oil rejuvenator remains very limited. This experimental study investigates the use of high percentages of RAP (i.e., up to 90%) in WMA using bio-oil rejuvenator. To this end, rheological tests including rotational viscosity (RV), multiple stress creep recovery (MSCR), and linear amplitude sweep (LAS) were carried out on different combinations of binders. Wheel tracking (rutting), indirect tensile stiffness modulus (ITSM), four-point bending beam fatigue, and moisture susceptibility tests were performed to evaluate the performance of the asphalt mixtures containing different binders. Test results demonstrated that the asphalt mixture with 90% RAP and a bio-oil rejuvenator had 37% higher fatigue life and 4% improvement in moisture resistance.