## 5 Conclusions and Recommendations  
In the article, it was proven that degradation caused by environmental impacts is significant and should be considered in asphalt mixture durability. In addition, it was proven that the decrease in pavement fatigue life caused by the action of water and frost, or road salt, is also significant and could even be several dozen percent. It is worth emphasizing that environmental factors affecting pavement fatigue life (based on fatigue criteria) have not been taken into account so far. The authors proposed some solutions and assumptions about how these environmental impacts could be considered. It is a noteworthy achievement regarding the actual state of knowledge. Eleven more important conclusions were drawn from the discussed results, which took into account asphalt mixtures and pavement construction modeling separately. 1. Water and frost or road salt impacts caused significant (up to 15%) material degradation. Environmental factors should be considered in asphalt mixture laboratory test procedures (especially fatigue life). 2. The degradation of mixtures caused by environmental factors (water and freeze, road salt) depends on the type of binder used in the mixture and the impact considered. 3. The mixtures containing highly modified 25/55/80 HIMA asphalt, demonstrated the highest (up to 2.88 times higher) resistance to water, frost, and road salt. Modifying the asphalt matrix by adding SBS polymer increases mixture resistance to environmental factors. 4. The presence of temperature-lowering additives (special waves or chemicals-WMA production technology) in the asphalt matrix increased the mixes' susceptibility to environmental factors. 5. The use of proprietary methods allows for a more comprehensive and straightforward study of the asphalt mixtures considering the environmental impacts-material could be reused for further tests, e.g., fatigue. 6. Increasing SBS polymer content in the asphalt matrix (25/55-60 (C4) vs. 25/55-80 HIMA (D4)) allowed for increasing mix resistance to water, frost, and road salt by up to 36%. 7. Applying the hot technology (in comparison to warm) enabled to increase in mix resistance (up to 2.47 times-B4 vs. A4) to analyzed environmental factors. 8. The developed degradation ratio \(DI_{(S)}\) based on stiffness modulus changes in the 4-PB test enables effective analysis of mixture degradation caused by water, frost, and road salt. Figure 12: Degradation ratio (DI \(\tau\)) considering stiffness changes in the mix. All the discussed pavement constructions revealed a significant decrease (up to 26%) in durability caused by environmental impacts. Water, frost, or road salt should be also considered in pavement durability. * Road salt impact is less destructive (from 18 to 63%) than water and frost impact considering pavement durability. * The pavement consisting of highly modified asphalt (25/55-80 HIMA) turned out to be up to 2.00 times more resistant to water and frost impact and up to 2.77 times more resistant to road salt impact. Mixtures based on polymer-modified bitumen should be used in constructions subjected to difficult environmental and traffic conditions. * The pavement consisting of WMA asphalt (35/50 WMA) could be up to 2.38 times less resistant to environmental factors than asphalts mixtures made in hot technology. It is not recommended to use mixtures produced in warm technology in areas where road salt usage is frequent or in roads built-in coastal regions where the impact of salt occurs throughout the year. Conceptualization, E.M.; methodology, E.M.; software, E.M.; validation, E.M. and P.M.; formal analysis, E.M.; investigation, E.M.; resources, E.M.; data curation, E.M.; writing--original draft preparation, E.M.; writing--review and editing, E.M. and P.M.; visualization, E.M.; supervision, E.M. and P.M.; project administration, E.M.; funding acquisition, P.M. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Not applicable.