Pavement performance is the ability of pavement to remain in an acceptable condition to serve the intended users over a period of time. There are several principal, combined factors that affect flexible pavement performance such as environmental conditions, pavement materials, and traffic loads. Vehicle overloading is considered one of the most significant causes of accelerating flexible pavement deterioration, reducing the pavement’s design life, and affecting the overall sustainability of the pavement system. Therefore, researchers are continuously examining pavement systems with a view to finding the most suitable solutions for sustainable development in road construction systems in order to reduce both costs and pollution. In this study, we present a framework to conduct nonparametric and parametric survival analysis for asphalt pavement test sections, to assess the influence of using reclaimed asphalt pavement (RAP) on fatigue service life, to indicate the most significant subset of risk factors (covariates), and to study the effect of overweight axles on flexible pavement performance. All the data concerned were extracted from the long-term pavement performance (LTPP) program. The Kaplan–Meier (KM) survival probability curves of multiple pavement distresses were developed to compare the failure probability for various distresses and to determine the median survival time for each distress. The fatigue survival curves for the test sections using RAP and virgin materials were developed separately and the equality of the two survival curves was tested and affirmed. Several parametric survival analyses were conducted to select the most significant subset of covariates. For fatigue cracking and, after dropping the insignificant predictors, a model was developed to show the quantitative relationship between fatigue failure time and potentially influential factors. The analysis indicated that the increase in the percentage of overloaded axles from 0% to 20% can reduce the fatigue survival life of flexible pavement by up to 55%. In the absence of overweight axles, a one-inch increase in asphalt layer thickness can extend the fatigue service life by about half a year. However, in the presence of 20% of overweight axles, a one-inch increase in thickness can extend the fatigue service life by only 0.22 years. Therefore, additional virgin materials and resources are needed to maintain traffic conditions in the road network and to compensate for the reduction in fatigue service life. Moreover, the effect of the increase in overweight axles from 0% to 15% on reducing the fatigue survival life is found to be similar to the effect of increasing the AADTT tenfold. Therefore, the sustainability of pavement is directly affected by the fatigue survival life.

Newer technologies such as warm mix asphalt (WMA) and reclaimed asphalt pavement (RAP) have gained international approval and have been considered as appropriate solutions that support the sustainability goals of the highway sector. However, both technologies present some shortcomings. The lower mixing and compaction temperatures of WMA reduce the binder aging and the bond between the aggregates and the coating binder, thus resulting in less rutting resistance and higher moisture susceptibility. On the other hand, RAP mixes tend to be stiffer and more brittle than conventional hot mix asphalt (HMA) due to the effect of aged binder. This tends to increase the crack propagation distresses. In an attempt to overcome their individual shortcomings, this study investigated the new concept of a combined WMA-RAP technology. The chemical WMA additive Rediset LQ1102CE was utilized with mixtures incorporating low (15%), medium (25%), and high (45%) RAP contents. Dynamic modulus (DM) and flow number (FN) tests were conducted to investigate the effect of Rediset on the behavior of RAP mixtures. The dynamic modulus |E*| mastercurves were developed using the sigmoidal model and Franken model was used to fit the accumulated permanent deformation curve. The results of this study showed that Rediset addition improved the cracking resistance of RAP mixtures. However, the rutting resistance was reduced but kept within the acceptable range except for mixtures containing low RAP content.

Due to the depletion of natural aggregates and high maintenance cost of highway systems, developing sustainable asphalt concrete (AC) mixes that use waste materials instead of virgin raw materials is necessary. A large amount of waste glass material is globally generated per year that could be beneficial to sustain the asphalt industry. In this context, the present paper evaluates the properties and performance of AC mixtures that utilize crushed waste glass as a replacement material of filler aggregates. Three AC mixes with percentages of filler replacement in the range from 0%, 25%, to 50% were fabricated. Complex modulus testing was performed to evaluate the dynamic modulus |E*| and phase angle δ over a range of temperatures and loading frequencies. In addition, the flow number (FN) test was conducted to assess the rutting potential of the mixtures. The results showed that the mix containing 25% of crushed glass is likely to better resist fatigue cracking; however, the inclusion of glass in the AC reduced the rutting resistance compared to conventional hot mix asphalt (HMA). Finally, the results of the flow number test and the simple performance indicators were compared and used to rank the mechanical performance of the various mixtures.