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The increasing volume of road traffic, heavier axle loads on pavements and extreme weather events have exposed the limitations of conventional asphalt pavements, particularly susceptibility to rutting, thermal cracking, and rapid aging [1,2], so that better performance of road construction materials are required.Despite their widespread use and despite the relatively low cost, conventional unmodified bituminous binders exhibit limited thermal stability and narrow operational temperature [3] and the poor resistance to oxidative degradation makes them prone to aging, leading to rutting at high temperatures and cracking at low temperatures [4]. One of the most effective approaches to enhancing the durability of asphalt concrete is modifying bitumen with polymers [5], which improves its rheological properties, increases deformation resistance, and slows aging processes [2].Among the most promising thermoplastic modifiers is ethylene-vinyl acetate (EVA), a copolymer of ethylene and vinyl acetate. Recent studies demonstrate that EVA-modified binders can reduce rutting by up to 80% while delaying oxidative aging due to their oxygen-scavenging capacity [4,6]. In addition, it was found capable of forming a three-dimensional network structure within bitumen [7]. This significantly increases stiffness and enhances the thermal resistance of the modified binder, thereby reducing pavement susceptibility to rutting [7,8]. Thorough research provided foundational evidence that EVA increases binder stiffness and elasticity at high temperatures and low frequencies, depending on bitumen-polymer compatibility and EVA concentration [9]. Findings from ref [10] confirm that both the concentration and molecular structure of EVA critically determine its effectiveness as a modifier. Moreover, the polar nature of EVA ensures good compatibility with bitumen and improves the material adhesive properties, also in the presence of water [11]. Another notable aspect of EVA is its potential in warm-mix applications due to its melt behavior, making it an attractive candidate for recycling-driven modification techniques [10]. However, EVA-modified binders can become overly rigid at low temperatures, resulting in brittle behavior that limits their use in cold regions [11].To offset the drawbacks of EVA and achieve a balanced set of properties, composite modifiers-such as combinations with crumb rubber or bio-oil additives-are increasingly being explored [4].In the context of growing attention to the environmental impact of construction, the reuse of waste materials, including polymeric and rubber-based waste, has become a key direction for sustainable development. This also to promote sustainability through waste valorization [12,13].For instance, a study [13] demonstrated that leather, rubber, and plastic waste account for the major share of disposal costs and volumes. An ever-increasing pressure on waste resources and environmental protection leads to a clear transition to a regenerative circular economy [14][15][16]. A large portion of these materials is still incinerated for energy recovery, whereas the adoption of reuse and recycling strategies could significantly reduce both environmental and economic burdens. Another study supports the viability of crumb rubber as a sustainable alternative to traditional modifiers [17] through a preblending technique improving compatibility, mechanical performance, and aging resistance in modified asphalt.Despite progress in bitumen polymer modification technologies, the effects of various secondary polymer additives-such as ground rubber waste and EVA granules-on the physicomechanical properties of asphalt concrete remain insufficiently studied. This research addresses that gap by examining the effects of EVA and rubber waste on asphalt mixture properties.In this context, Crumb rubber, derived from end-of-life tires, offers a complementary solution. Its viscoelasticity enhances crack resistance at low temperatures and dampens trafficinduced vibrations [12]. Together with improving rutting resistance, EVA uniquely contributes to low-temperature flexibility, making it a balanced modifier for climate resilience [18].Yet, challenges persist, including incomplete compatibility with bitumen and higher production temperatures [4]. Recent advances in hybrid modification (e.g., EVA-rubber blends) aim to balance these properties, though mechanistic understanding remains incomplete [19].Specifically, this research investigates the influence of these modifiers on strength, deformation, and moisture-related performance indicators, including water absorption, water resistance, compressive strength, crack resistance, and shear stability. By combining rheological testing, FTIR spectroscopy, and lifecycle cost analysis, the study aims to provide a more comprehensive understanding of how secondary polymer modifiers influence the behavior of asphalt concrete, providing a roadmap for optimizing polymer-modified asphalt mixtures in diverse climates. The work is notable. The construction sector generates 1.3 billion tons of polymer waste annually, with tire rubber and EVA-based packaging contributing significantly to landfill burdens [18] so their incorporation into asphalt would lead to undiscussed economic and environmental benefits. For instance, every ton of crumb rubber used in asphalt diverts 300 passenger tires from landfills while cutting production costs by 15-20% [12]. This also would align with UN Sustainable Development Goals (SDGs 9, 11, and 12) by reducing raw material consumption and CO₂ emissions [19].This study utilized road bitumen of grade BND 70/100. The main physical and mechanical properties of the bitumen used are presented in Table 1. Crumb rubber and EVA granules, shown in Figure 1, were used as industrial waste-based modifiers. To evaluate the effectiveness of these additives, a dry mixing method was applied.According to this method, the dosage of modifiers was set at 20% of the bitumen mass. This proportion was selected based on previous studies by other researchers [20].Fig. 1. Appearance of the modifiers: A -EVA granules; B -crumb rubber.The asphalt concrete type B mixtures with modifiers were prepared by weighing the calculated amount of raw materials, heating the aggregates in a drying oven to the required temperature (180-185 °C), adding the modifiers and bitumen, and mixing the components in a laboratory paddle mixer. Mixing was carried out until a visually homogeneous blend was achieved.To prepare asphalt concrete of type B, in addition to bitumen and modifiers, the following mineral aggregates were used:1) Crushed gravel aggregates (fractions 10-20 mm and 5-10 mm);2) Sand from crushed stone screenings (fraction 0-5 mm);3) Activated mineral filler MP-1.All raw materials were tested for compliance with current standards. The particle size distributions of the gravel, sand, and mineral filler were determined. The physical and mechanical characteristics of the aggregates are presented in Tables 234. The crushed gravel aggregates are of high quality, exhibiting strong mechanical strength, high abrasion resistance, and adequate frost resistance for use in moderate climatic conditions.Low water absorption and a high percentage of crushed particles ensure good adhesion to the bituminous binder and contribute to the overall stability of the asphalt concrete mixture. At the second stage of the study, samples of type B asphalt concrete mixture were prepared in accordance with the requirements of standard ST RK 1225-2025, with a bitumen content of 5.0%. To evaluate the effect of modifying additives, a series of experimental mixtures was produced by incorporating 20% modifier by weight relative to the bitumen content. A reference mixture without any additives was used as the control sample. The distribution of mineral components in the mixture is presented in Table 5. The physical and mechanical characteristics of asphalt concrete mixtures were investigated in accordance with the requirements of international ASTM standards. The samples were tested using the following indicators:Water saturation was determined as the ratio of the mass of water absorbed by the sample to its dry mass, in accordance with ASTM D2726. Compressive strength was measured at temperatures of 20 and 50 °C in accordance with ST RK 1218. Moisture resistance under prolonged water saturation was assessed as the ratio of the strength of the water-saturated sample to the strength in a dry state, following ASTM D4867. Crack resistance was determined based on tensile strength at splitting at 0 °C and a deformation rate of 50 mm/min, in accordance with ASTM D6931. Shear stability was evaluated using the internal friction coefficient and shear adhesion measured at 50 °C.The resistance of asphalt concrete mixtures to plastic deformation was assessed according to the European standard EN 12697-22. This method simulates cyclic vehicular loads on the specimen at 60 °C, enabling conditions close to real-life pavement operation in hot climates. The rut depth was measured after 10,000 wheel passes. Three types of type B asphalt concrete mixtures were prepared for the test: a control mixture (without modifier), a mixture with 25% rubber granulate, and a mixture with 25% EVA granules (based on the binder mass).To assess the chemical changes occurring in bitumen as a result of modification, Fouriertransform infrared spectroscopy (FTIR) was employed. The analysis was carried out in the range of 4000-400 cm⁻¹ using an ALPHA II spectrometer.This study presents a comprehensive evaluation of the effect of secondary polymer modifiers on key physical and mechanical properties of asphalt concrete mixtures. The aim of the analysis was to determine the degree of improvement in performance characteristics with the addition of EVA granules and rubber granulate, as well as to identify differences in their mechanisms of action.Particular attention was paid to parameters such as compressive strength at different temperatures, water saturation, moisture resistance, crack resistance, shear stability, and rutting resistance. These indicators are critically important for assessing the durability and operational reliability of road pavements under variable climatic and mechanical loads.Analysis of the control type B asphalt concrete mixture (Table 6) showed that the compressive strength at 50 °C was 0.9 MPa, and the shear adhesion was 0.21 MPa. These values indicate insufficient thermal stability and low resistance to plastic deformation, which may limit pavement durability in hot climates and under heavy traffic. Therefore, it is necessary to modify the mixture to enhance its performance characteristics in accordance with international road construction standards and methodologies. The introduction of secondary polymer additives had a significant effect on the properties of asphalt concrete mixtures. According to the data presented in Table 7, the use of rubber granulate led to a reduction in the water saturation of asphalt concrete from 2.7 to 2.4%, indicating increased density and structural homogeneity of the mixture. Similar observations are reported in [12], where it was shown that rubber particles enhance the contact between the binder and the mineral skeleton, contributing to a reduction in air voids and improved moisture resistance.At the same time, the addition of EVA granules resulted in an increase in water saturation of the asphalt concrete to 3.3%. This may be attributed to the polar nature of the modifier itself, as well as its less effective adhesion to mineral components and bitumen. Moreover, when using the dry mixing method, EVA granules may distribute unevenly, causing local structural defects and increased porosity. Despite this, mechanical properties such as crack resistance and rutting resistance showed significant improvement, confirming the effectiveness of EVA as a modifying additive when the dosage and mixing technology are properly selected. For instance, the use of 25% EVA granules increased the thermal resistance of the mixture, doubling crack resistance at 0°C doubling from 3.0 to 6.9 MPa. Compressive strength also increased to 2.2 MPa compared to the control sample (0.9 MPa).Physical and mechanical characteristics of modified asphalt concrete. Thus, modification with EVA granules contributes to the formation of more thermally stable and crack-resistant asphalt concrete. These results confirm the high efficiency of EVA as a modifier, provided that the optimal component ratio is maintained.The resistance of asphalt mixtures to plastic deformation under prolonged loading is one of the key criteria for their operational reliability. This parameter is especially important in regions with hot climates and heavy traffic, where rutting significantly reduces the service life of the pavement.As part of this study, three types of asphalt mixtures were analyzed: a control mixture (without modifiers), and compositions containing 25% EVA granules and rubber granulate. A comparative analysis of the results (Fig. 2) allows assessment of the effectiveness of the modifiers in improving resistance to plastic deformation.Analysis of the experimental data (Fig. 2) shows a significant reduction in rut depth when polymer modifiers are used. In the control mix without additives, the residual deformation reached 4.9 mm after 10,000 wheel passes at a temperature of 60 °C, indicating high susceptibility to plastic flow. The addition of 25% rubber granulate reduced this value to 3.5 mm, reflecting a partial improvement in the structural stability of the pavement. The most pronounced effect was observed with EVA granule modification: the rut depth was only 0.77 mm, which represents an almost 85% reduction compared to the control mix.These results confirm the high efficiency of EVA as a modifier capable of significantly enhancing the resistance of asphalt pavement to permanent deformation, due to the formation of a network structure within the bitumen matrix and improved rheological performance at elevated temperatures.FTIR spectroscopy has been chosen as an investigative tool because it can give information on the degrees of inter-and intra-molecular interactions in the systems under study.Fig. 3 presents the FTIR spectra of the original asphalt concrete and its modified forms with EVA granules and rubber crumb. All spectra show characteristic absorption bands: stretching vibrations of C-H bonds in alkyl groups (~2920 and ~2850 cm⁻¹), deformation vibrations of CH₂/CH₃ (~1455 cm⁻¹) and CH₃ (~1375 cm⁻¹), as well as a band around 1030 cm⁻¹ associated with S=O group vibrations [21]. Complete band attribution is reported in Table 8. Infrared frequencies of functional groups and their assignments. It is worth noting the presence of a weak and broad band at the very high side frequency in the 4000-3350 cm⁻¹ range. Magnified portion is reported in Fig. 4.!""" #A"" #""" BA"" B""" CA"" C""" A"" "'! "'A "'( "')"'* "'+ C'",-./01233./456T89 :.;5/<1=5-6T41 >C 9 6? 6@ 6A Fig. 4. Magnified portion of the 3250-4000 cm -1 range of the FTIR spectra.This feature is generally due to the OH or NH functional groups in bound molecules, with a sharp contribution at 3640 cm⁻¹ emerging from the broad band and most probably due to the presence of some monomers (not interacting OH-or NH-containing molecules). While both O-H and N-H stretches appear in the general vicinity of 3300 cm⁻¹, the width and intensity of the peaks, along with other spectral data, can be used to distinguish between them. O-H stretches are generally broader and stronger, while N-H stretches are typically narrower and weaker, due to differences in hydrogen bonding and electronegativity [22]. This band feature is typical of crumb rubber due to its content in O and N atoms, and consequently the bitumen containing it exhibits the corresponding IR feature. However, in absence of further accompanying information it is hard to distinguish what kind of amine/alcohol is involved from the purely IR band detection.!""" #AB" #B"" #CB" Perusal of the 3000-2800 cm -1 spectral range, which is reported in Fig. 5, can give further interesting information. In this region the peaks are due to the symmetric and antisymmetric stretching (nS and nAS respectively) of CH2 and CH3 groups, as indicated in the figure as labels.Considering that these groups are located along the alkyl chain forming aliphatic portions of the molecules, most reasonably located in the maltene fraction of the system, the relative intensity ratio of such peaks is sensitive to the molecular lateral packing of the alkyl chains, as found in some model systems [23].It must be pointed out that an increase in the lateral packing order of the alkyl chains results in a decrease in the intensity of the CH2 symmetric stretching band relative to the CH3 antisymmetric stretching band [24,25].It can be seen, here, that no difference in any of the peak positions takes place. This shows that a change in the lateral packing of the alkyl chains both in the skeletal CH2 groups and in the terminal CH3 groups is ruled out. Only some small deviations, just above from the statistical error, takes place in the intensity, but it affects almost in the same way all the four contributions, ruling ! ?B AC # ! B AC ! ! B AC #also out changes in relative intensity among these absorptions. Consequently, the local structure experienced by the alkyl chains is not dependent on the presence of EVA or crumb rubber. This is an indication that the of the most in the fraction is not by the presence or absence of crumb rubber or EVA granules, reasonably due to the interactions with them. the addition of such materials the of with and the interactions of bituminous with the or crumb particles can only their with the results that such interactions must be The that of the have chemical and low to interactions with EVA and crumb rubber, the modification of asphalt concrete with rubber crumb is by the or of a band in the cm⁻¹ characteristic of vinyl of as well as in the intensity of in the cm⁻¹ range. shown in the same Fig. remains almost reflecting the stability of the of the modified spectra of asphalt concrete modified with EVA show the of a peak at cm⁻¹, associated with vibrations may to the stretching of This may indicate the formation of or functional groups as a result of interactions between EVA and the components of the bituminous which is with the reported in [9]. the peak at cm -1 due to the functional group absorption, is in the of bitumen, it is characteristics of this the FTIR spectra confirm the presence of functional groups associated with EVA and rubber as well as their chemical with the asphalt concrete. EVA modification has a more pronounced effect on the chemical structure of the binder due to the introduction of polar groups, whereas rubber granules the physical structure of the assess the of using secondary polymer modifiers, a evaluation was to the impact of EVA granules and rubber crumb on the cost of asphalt concrete mixtures and the overall of road this the dosage of polymer modifiers was set at 25% by weight of the binder in the asphalt mixture, as this proportion provided the performance in of strength, crack resistance, and deformation stability. This dosage was as a reference to the effect of polymer additives on the overall cost of the pavement. The are based on current for the materials costs associated with and However, the performance characteristics through modification are to reduce the for and thereby the overall economic viability of this shown in Table 9, the economic is when using EVA granules, which is attributed to their cost compared to crumb rubber, as well as a significant reduction in the overall cost of the asphalt mixture. The resulting can up to compared to the unmodified be that the presented are based on of materials and an modifier dosage by binder The economic evaluation only the material and the improvement in performance characteristics of the modified mixtures can reduce the frequency and volume of further the economic of the study presented a comprehensive evaluation of the impact of secondary polymer granules and crumb the performance of type B asphalt concrete mixtures. The results demonstrated that both modifiers enhance the mechanical and durability properties of the the degree of improvement addition of EVA granules led to a notable increase in rutting resistance rut depth to 0.77 improved cracking resistance to 6.9 and compressive strength at elevated Crumb rubber also showed a particularly in improving water resistance, its overall impact was less pronounced compared to spectroscopy the different modification the structural of EVA and the physical influence of rubber the analysis showed that the use of EVA granules offers the cost to while reducing environmental impact through the recycling of polymer the use of EVA granules as a bitumen modifier represents an effective and sustainable to enhancing the reliability and of asphalt research on assessing the performance of the modified mixtures under low-temperature the influence of climatic and to the laboratory under