Rheological Properties Of Binders Research Articles

Evolution of Rheological and Microscopic Properties of Asphalt Binders under Fuel Corrosion

Vehicle fuel leaks can adversely affect the performance of asphalt pavements. To study the mechanisms of fuel corrosion damage in asphalt, four asphalt binders were selected in this study, and the evolution of their rheological and microscopic properties was investigated. Fuel corrosion caused continuous mass loss in asphalt binders. Base asphalt lost more than 50% of its mass after 24 h of fuel corrosion, while modified asphalts had better resistance. According to dynamic shear rheometer tests and multiple stress creep recovery tests, modifiers improved the high-temperature rheological properties of these asphalt binders. As the degree of fuel corrosion deepened, the indexes characterizing the high-temperature performance deteriorated. Rubber-modified asphalt showed the best resistance to high-temperature deformation, while the performance of LDPE-modified asphalt was more stable. In contrast, fuel corrosion improved the resistance of asphalt binders to low-temperature cracking to some extent: the creep strength (S) decreased as the creep rate (m) increased, and the resistance of SBS-modified asphalt to low-temperature cracking was optimal, with a 36% decrease in S-value after 24 h of fuel corrosion. Fourier transform infrared spectroscopy tests showed that diesel corrosion was a process of this physical dissolution, with no change in the chemical functional groups. Meanwhile, by using fluorescence images and analyzing the four-component test results, we found that fuel corrosion disrupted the stabilized structure formed by the modifiers, and the heavy components in the asphalt binders were converted into light components. This study reveals the evolution of the rheological and microscopic properties of asphalt under fuel corrosion, which can provide a reference for the optimization of fuel corrosion resistance in asphalt pavement.

Evaluation of Rheological and Microscopic Properties of SBS-Modified Asphalt Binder with Multiple Regeneration

Evaluation of Rheological and Microscopic Properties of SBS-Modified Asphalt Binder with Multiple Regeneration

A Bayesian deep learning approach for rheological properties prediction of asphalt binders considering uncertainty of output

Traditional methods for assessing rheological properties are often time-consuming, labor-intensive, and subject to operator bias. Moreover, conventional deep learning models may suffer from overconfidence in their predictions, limiting their applicability in real-world scenarios. A Bayesian deep learning framework that provides accurate predictions of asphalt binder rheological properties and quantifies the associated uncertainties is proposed to address these challenges. Atomic Force Microscopy images were employed as input values for the model, and the Dynamic Shear Rheometer test for the rheological property measurements was used. The proposed Bayesian deep learning model used Markov Chain Monte Carlo techniques to estimate model parameters and associated uncertainties. The effectiveness of the approach through an application involving multiple additives to validate the generality of the proposed framework was demonstrated. The results indicate that the Bayesian deep learning model offers improved prediction accuracy, reduced testing time, and operator-independent results compared to conventional methods. Additionally, quantifying uncertainties in predictions enable more informed decision-making and risk assessments in asphalt binder selection and pavement design. Overall, this study provides a novel and robust approach for predicting the rheological properties of asphalt binders, paving the way for more efficient and reliable pavement engineering practices.

Preparation and characterization of polyurethane-modified asphalt containing dynamic covalent bonds

Self-healing behavior of binder has important potential for promoting low-carbon service and extending service life of asphalt pavement. A novel self-healing polyurethane modified asphalt with dynamic covalent bonds was prepared in this work. The chemical structure, thermal-oxygen stability, rheological properties, fatigue properties and self-healing capability of polyurethane modified asphalt with dynamic covalent bonds were systemically investigated through Fourier infrared spectrum test, thermal gravimetric test, dynamic shear rheology test, linear amplitude sweep(LAS) test and multiple fatigue-healing-fatigue test. The result indicates disulfide dynamic covalent bond and oxime urethane dynamic covalent bond were successfully introduced into polyurethane cross-linking structure in asphalt, and the thermal-oxygen stability of asphalt has a significant increase after modification under the environmental conditions of construction and service. Rheological properties analysis suggests the introduction of dynamic covalent bonds is beneficial to improve the low-temperature toughness of polyurethane modified asphalt, and enhances its low-temperature cracking resistance. LAS analysis indicates the fatigue life of polyurethane modified asphalt can also be lengthened by over 70% at different strain levels(1.5%, 2.5% and 5%) with the introduction of dynamic covalent bonds, which is attributed to the excellent conformation adjustment ability and stress dissipation ability of dynamic cross-linking structure in asphalt. The multiple fatigue-healing-fatigue test shows the self-healing capability of polyurethane modified asphalt has an improvement with the introduction of dynamic covalent bonds, especially at the later stage with serious fatigue damage, and oxime urethane dynamic covalent bond shows the better contribution effect as compared with disulfide bond. This is due to the reversible fracture-rearrangement characteristics of dynamic covalent bonds. This work provides a new idea for improving the self-healing capacity and rheological properties of binder, reducing the frequency of pavement maintenance and extending the pavement service life.

Use of Random Forest to Predict Intermediate Temperature SCB Jc Parameter of Long-Term Aged Asphalt Mixtures

With the growing use of reclaimed asphalt pavement (RAP), recycled asphalt shingles (RAS), and other innovative additives in asphalt mixtures, there are concerns about the accuracy of Superpave volumetric-based mixture design. Performance tests in mix design procedures are needed to ensure desirable pavement performance. The Louisiana Department of Transportation and Development (LADOTD) has adopted the semi-circular bend (SCB) critical strain energy release rate parameter, Jc, to evaluate the cracking resistance of asphalt mixtures. To address practical shortcomings, this study aims to develop a predictive model to estimate SCB Jc at intermediate temperature of long-term aged (LTA) asphalt specimens from volumetric properties of plant-produced asphalt mixtures, and rheological and chemical properties of unaged asphalt binder by using a machine-learning model, random forest. Asphalt mixture SCB test and asphalt binder rheological and chemical properties tests were conducted. Stepwise correlation analysis was used to determine the most influential variables to SCB Jc. Random forest model was optimized using grid search with hyperparameter combinations. Results show that the developed random forest model was able to predict the SCB Jc fracture parameter of asphalt mixtures and a good agreement was observed between predicted and measured SCB Jc values. Variable importance scores based on mean decrease in impurity (MDI) showed that the Δ Tc had the most influence on SCB Jc prediction accuracy, and other inputs such as coarse aggregate type, LTA days, Fourier transform infrared spectroscopy test carbonyl index, and linear amplitude sweep test ALas also had significant effects on SCB Jc.

Effect of chemical warm-mix additives on asphalt binder rheological and chemical properties in the context of aging

Warm-Mix Asphalt (WMA) has achieved gradually increasing popularity among researchers and agencies because of the environmental and economic benefits associated with lower production temperatures. An ongoing research study sponsored by the Oklahoma Department of Transportation (ODOT) is focusing on evaluating how different chemical WMA additives and the associated lower production temperatures impact asphalt binder and mixture properties and exploring potential relationships between asphalt rheology and chemistry in the context of chemical WMA and various aging conditions. This manuscript presents partial findings from this study that involved testing of two binder types (modified and unmodified binder) and four different WMA additives (chemical additives). Different aging conditions were simulated by changing the Rolling Thin Film Oven (RTFO) temperature, and by subjecting the binder to different cycles of Pressure Aging Vessel (PAV) aging. Frequency and Temperature Sweep tests by a Dynamic Shear Rheometer (DSR) and Bending Beam Rheometer (BBR) tests were performed for rheological characterization, while Fourier Transform Infrared Spectrometer (FTIR) test was conducted for chemical characterization. Analysis of the test results indicated that while all the WMA additives can improve the rheological and chemical properties of control binders at original and RTFO conditions, two additives cause inferior properties after 20 h, 40 h, and 60 h of PAV aging, indicating possible higher aging susceptibility and long-term performance concerns. Good correlations (R2 greater than 0.8) observed between binder rheological parameters and chemical indices indicate the existence of fundamental relationships between asphalt binder’s engineering properties and chemical make-up, which also supports the possibility of using FTIR as a quick screen or fingerprint tool for binder selection and comparison. Two new rheological parameters have been proposed for evaluation of the polymer-modified binder in this study. This was important to address the presence of multi-transition behavior in modified binders. These two parameters show consistent trends with increasing aging conditions.

A Study of the Rheological, Physicomechanical, and Thermomechanical Properties of Epoxy Binders with Various Curing Agents

A Study of the Rheological, Physicomechanical, and Thermomechanical Properties of Epoxy Binders with Various Curing Agents

Investigation of the Rheological Properties of Asphalt Binders Modified with Nanomaterial

This study examined the effects of the Aerosil 150 addition on the rheological characteristics of bituminous binders at various temperatures. In the study, a frequency sweep test was applied to determine the rheological properties of pure binders and binders with 2%, 4% and 6% Aerosil 150 additives. Unaged binders were subjected to the frequency sweep test using a Bohlin DSR rheometer at test temperatures ranging from 40°C to 80°C (increasing by 10°C). The results showed that adding Aerosil 150 additive to the pure binder raised the binder's complex modulus (G*) values while decreasing the phase angle (δ) values. At 40 °C 0.1 Hz frequency, 2%, 4% and 6% Aerosil 150 doped binders gave G* values 1.52, 2.02 and 3 times higher than pure binder, respectively. The same ratio is 1.31, 1.54 and 1.99 times at 5 Hz frequency and 1.28, 1.47 and 1.82 times at 10 Hz frequency. At the same temperature, as the frequency value increases, the binders' complex modulus values approach each other. When the phase angle values at 40°C were examined, the 2%, 4%, and 6% Aerosil 150 modified binders, when compared to pure binder at 0.1 Hz frequency, yielded 2.75°C, 5.56°C, and 9.17°C lower phase angle values, respectively. This decrease is 3.19, 5.04 and 7.33 °C at 5 Hz frequency and 3.09, 4.84 and 6.76 °C at 10 Hz frequency. This shows that at various frequencies, the modified binder behaves more adaptably than the pure binder. The fact that the binder has a low δ value against a high G* value indicates that it will exhibit more flexible behavior. It was discovered as a result that Aeresil 150 modified binders performed better in terms of rheological qualities than pure binders.

Characterizing the Aging and Performance of Asphalt Binder Blends Containing Recycled Materials

Abstract The aging of asphalt concrete is mainly governed by the aging of the asphalt binder, which is a naturally occurring organic hydrocarbon. Both chemical and rheological properties of asphalt binder are expected to change as aging continues. The pavement industry is increasing the use of different recycled materials in the construction and rehabilitation of flexible pavements to preserve natural resources, save costs, and reduce environmental emissions. The aged binder from recycled materials is expected to alter the binder properties and its aging characteristics in the new mix. In this study, 3 different virgin base binder types (PG 64-16, PG 58-22, and PG 70-10) and 7 different binder blends containing recycled binders (up to 100 % binder replacement) were subjected to different aging conditions. The rheological and chemical properties of these binders were characterized using a dynamic shear rheometer and Fourier transform infrared spectroscopy, respectively. It was found that the Glover-Rowe parameter distinctively captured the change in binder rheological properties with aging for the different binder blends. A good correlation (R2 value of 0.83–1.00) was observed between binder chemical and rheological properties. The source and performance grade of the base binder were found to govern the correlation between the rheological and chemical properties of the blended binder. Hamburg wheel tracking (for rutting and moisture sensitivity) and indirect tensile asphalt cracking test (for fracture) tests were conducted on asphalt mixes maintaining the same blended binder ratios. The laboratory mix performance parameters were found to correlate well with the properties of the blended binders. Therefore, properties of the blended binders can be an important source of information for predicting the performance of asphalt mixes containing recycled materials.

Application of bio-resin in road materials: Rheological and chemical properties of asphalt binder modified by lignin-phenolic resin

The development of new sustainable green road materials with bio-resin is a hot topic in pavement engineering. To improve the efficiency of lignin as a sustainable pavement material, an asphalt binder modified by lignin-based resin was prepared, and its properties were evaluated. Firstly, lignin was extracted from biomass (corn straw) by thermochemical method to prepare lignin-based phenol formaldehyde (LPF) resin. After that, LPF resin-modified asphalt and phenol formaldehyde (PF) resin-modified asphalt were prepared. Then the effects of LPF resin and PF resin on asphalt properties were evaluated by chemical analysis and rheological performance tests. The results showed that lignin was involved in resin synthesis, LPF resin with PF resin had similar thermogravimetric curves, and the thermal stability of LPF resin was slightly lower than PF resin. Both LPF resin and PF resin can increase the proportion of large-size molecules and elastic components of asphalt binder and enhance its high-temperature deformation recovery ability. Moreover, the fatigue performance and aging resistance of the binder were also enhanced by the addition of LPF resin and PF resin. Although the addition of LPF resin and PF resin will increase the G-R parameters of virgin asphalt binder, it can reduce the effect of aging on the G-R parameters of asphalt binder. It seems that LPF resin and PF resin can improve the cracking resistance of asphalt binders.

Evaluation of long-term oven aging protocols on field cracking performance of asphalt binders containing reclaimed asphaltic materials (RAP/RAS)

This study compared two loose mixes’ long-term oven aging (LTOA) protocols (i.e., 5-day at 95°C and 8-hour at 135°C) based on asphalt binder rheological and chemical properties. The protocols were then correlated with field aging conditions. Extracted and recovered asphalt binders from four asphalt mixtures were tested in the Dynamic Shear Rheometer (DSR), Bending Beam Rheometer (BBR), Double-Edge-Notched-Tension (DENT) Test, and Fourier Transform Infrared Spectroscopy by Attenuated Total Reflectance (FTIR-ATR). Based on the research results, the loose mix aging protocol of 5-day at 95°C replicates the effects of 2- and 3-year field oxidative aging on the rheological and chemical properties of the binders. The laboratory protocol of 8-hour at 135°C yielded a higher level of aging to the binders compared to the 5-day at 95°C protocol. Additional testing is planned to determine if these loose mix LTOA protocols can simulate 4–5-year field aging in Alabama.

Rheological investigation on the ageing performance of bio-recycled asphalt binders and mixtures

The current need to move towards more sustainable technologies in the construction sector has promoted the investigation of using alternative materials in asphalt mixtures for pavements. Biomaterials, used as biobinders, have shown their potential as partial replacement of bitumen in asphalt mixtures as solution to decreasing the demand for fossil-fuel-based binders as well as CO2 emissions. However, more research is needed to increase the replacement of bitumen in asphalt mixtures. In this investigation,biobinders are used as full replacement of virgin bitumen and as recycling agent within asphalt mixtures with high Reclaimed Asphalt (RA) content. Blends of biobinders and RA binders, and bio-recycled asphalt mixtures, were produced, subjected to ageing and rheologically characterised. The results show that the rheological properties of binders’ blends seem adequate for their use, while the bio-recycled asphalt mixtures seem to have a faster ageing than conventional ones, hence their full-scale application still remains a concern.

Rejuvenation of aged asphalt binders by waste engine oil and SBS blend: Physical, chemical, and rheological properties of binders and mechanical evaluations of mixtures

Due to the poor cracking performance of aged binders, the use of reclaimed asphalt pavement (RAP) in road pavements is limited. When applying a greater RAP percentage, the use of a rejuvenator is necessary. The rejuvenator's unfavourable softening impact, on the other hand, causes the pavement to be vulnerable to rutting. As a result, RAP binders with optimized rutting and fatigue cracking properties are required. Therefore, this study was carried out to evaluate the simultaneous effects of 70% waste engine oil (WEO) and 30% SBS copolymer as a compound rejuvenator (WS-rejuvenator) on the performance of asphalt binders and mixtures containing RAP binders of 30% and 50%. The physical, chemical and rheological properties of asphalt binders were evaluated using the conventional tests, SARA (Saturate, Aromatic, Resin, and Asphaltene) analysis, FTIR test, thermal gravimetric analysis (TGA), DSR, and BBR. The mechanical properties of mixtures were examined using the Marshall, indirect tensile strength, moisture damage, rutting, and aggregate coating tests. The findings showed that WS-rejuvenator at 5% and 10% recovered the physical characteristics of asphalt binders containing 30% and 50% RAP, respectively. Furthermore, WS-rejuvenator was able to compensate for the light components of the RAP binder that were lost over time. As a consequence, the behavior of the RAP binder at high, moderate, and low temperatures was recovered to that of the virgin binder. By mixing the RAP binder with the compound rejuvenator, the oxygenation indices were effectively reduced. The TGA revealed that the thermal stability of regenerated binders was equivalent to that of the virgin binders. In addition, the mechanical properties of regenerated mixes were enhanced in comparison to the control mixture. In summary, the adoption of RAP and WEO-SBS rejuvenator in asphalt mixtures show promising outcomes to enhance greener pavement materials application in the future.

Rheological and adhesive properties of nanocomposite bitumen binders based on hydrophilic or hydrophobic silica and modified with bio-oil

Improved adhesive and cohesive properties of bitumen blends with bio-oil and two types of silica nanoparticles having either hydrophilic or hydrophobic surface were studied. The morphology of the modified bitumen and its rheological properties at normal and elevated temperatures were also investigated in detail. The addition of 5–20 wt% bio-oil leads to the appearance of a small yield stress in the bitumen melt and a reduction in the loss tangent for the cooled mixture. At the same time, the addition of 5% bio-oil is the most optimal, as it results in an increase of the thermodynamic work of adhesion and the measured adhesive strength of the bitumen binder to the silicate surface by 16–21%. The addition of silica nanoparticles in quantities up to 15 wt% causes a more significant increase in the yield stress as well as an even greater improvement in the stiffness and elasticity of the bitumen binder at normal temperature. Moreover, the nanoparticles increase the cohesive strength of the bitumen binder up to 60% and bidirectionally change its adhesion characteristics, depending on the nature of their surface. At a concentration of 15 wt%, the hydrophobic silica doubles the adhesion of the binder to steel, whereas the hydrophilic one conversely halves it.

Relationship between colloidal index and chemo-rheological properties of asphalt binders modified by various recycling agents

This paper examines relation between colloidal index (CI) and chemo-rheological properties of asphalt binders modified by five different recycling agents (RAs) including paraffinic oils, aromatic extracts, naphthenic oils, triglycerides/fatty acids, and tall oils. To monitor the change of binder properties, each binder was exposed to different aging conditions. Saturates, aromatics, resins and asphaltenes content of each modified binder, as well as its rheological and low-temperature cracking properties were determined before and after aging. It was found that recycling agents could vary the softening and long-term performance of the modified binders based on their chemical makeup. While all RAs softened the binder, only few could restore binder rheological properties. The study results revealed a strong linear relation between the CI and the chemo-rheological properties of binders. For instance, the flexural creep stiffness and Log complex modulus found to inversely related to CI while the phase angle and relaxation constant (m-value) found to be directly related to CI. The study results highlight the source dependency of RAs’ efficacy to restore and maintain binder properties after aging.

Evaluating the Rheological Properties of High-Modulus Asphalt Binders Modified with Rubber Polymer Composite Modifier

With the increasing traffic loading and changing climatic conditions, there is a need to use novel superior performing pavement materials such as high-modulus asphalt binders and asphalt mixtures to mitigate field distress such as rutting, cracking, etc. This laboratory study was thus conducted to explore and substantiate the usage of Rubber Polymer Composite Modifier (RPCM) for high-modulus asphalt binder modification. The base asphalt binder used in the study comprised A-70# Petroleum asphalt binder with RPCM dosages of 0.25%, 0.30%, 0.35%, 0.40% and 0.45%, separately. The laboratory tests conducted for characterizing the asphalt binder rheological and morphological properties included the dynamic mechanical analysis (DM), temperature-frequency sweep in the dynamic shear rheometer (DSR) device, bending beam rheometer (BBR), and florescence microscopic (FM) imaging. The corresponding test results exhibited satisfactory compatibility and potential for using RPCM as a high-modulus asphalt binder modifier to enhance the base asphalt binder’s rheological properties, both with respect to high- and low-temperature performance improvements. For the A-70# Petroleum asphalt binder that was evaluated, the optimum RPCM dosage was found to be 0.30–0.35%. In comparison to styrene–butadiene–styrene (SBS), asphalt binder modification with RPCM exhibited superior high-temperature rutting resistance properties (as measured in terms of the complex modulus and phase angle) and vice versa for the low-temperature cracking properties. Overall, the study beneficially contributes to the literature through provision of a reference datum toward the exploratory usage of RPCM for high-modulus asphalt binder modification and performance enhancements.

Rheological and chemical properties of field aged binders and their variation within the wearing course

Field ageing is investigated based on recovered binders. Fifteen sections were considered, consisting of unmodified and polymer-modified binders (PmB). Binders were recovered from the wearing course, after slicing the cores horizontally. To assess field and laboratory ageing tendencies, recovered binders were compared to a set of reference binders, tested before and after laboratory ageing. For three sites, the binders recovered from bottom slices were long-term aged and compared to the properties of top slices. Stiffness-based rheological parameters showed good relations to the carbonyl index. Field and laboratory ageing induced the same trends, but field ageing often turned out to be more severe. It was shown, for three sections, that a standard ageing test applied to the bottom slices is not enough to reach the ageing levels of the top slices. Finally, a relation between the vertical ageing profile and the void content of the corresponding asphalt mixtures was observed.

Rheological, physicochemical, and microstructural properties of asphalt binder modified by fumed silica nanoparticles

Warm mix asphalt (WMA) is gaining increased attention in the asphalt paving industry as an eco-friendly and sustainable technology. WMA technologies are favorable in producing asphalt mixtures at temperatures 20–60 °C lower in comparison to conventional hot mix asphalt. This saves non-renewable fossil fuels, reduces energy consumption, and minimizes vapors and greenhouse gas emissions in the production, placement and conservation processes of asphalt mixtures. At the same time, this temperature reduction must not reduce the performance of asphalt pavements in-field. Low aging resistance, high moisture susceptibility, and low durability are generally seen as substantial drawbacks of WMA, which can lead to inferior pavement performance, and increased maintenance costs. This is partly due to the fact that low production temperature may increase the amount of water molecules trapped in the asphalt mixture. As a potential remedy, here we use fumed silica nanoparticles (FSN) have shown excellent potential in enhancing moisture and aging susceptibility of asphalt binders. In this study, asphalt binder modification by means of FSN was investigated, considering the effects of short-term and long-term aging on the rheological, thermal, and microstructural binder properties. This research paves the way for optimizing WMA by nanoparticles to present enhanced green asphalt technology.

Impact of the asphalt binder rheological behavior on the value of the ΔTc parameter

The current Performance Grading system for asphalt binders in the USA, determines limiting temperatures for appropriate binder use. Practically, the low limiting temperature is based on rheological measurements made using the Bending Beam Rheometer (BBR). The absolute value of the creep modulus and/or its slope vs loading time in a log scale, are being used. However, the current specifications are being challenged and it has been proposed adding a new criterion, called ΔTc; its ability to better predict thermal cracking is the subject of intense discussions. In this paper, we mathematically show how ΔTc relates to other binder rheological properties. Then, we discuss the practical consequences in order to highlight the relevant parameters controlling ΔTc. Experimental data are used to substantiate the main findings. This shows that ΔTc is of “pure” rheological origin and care must be taken when trying to predict cracking results from rheological data only.

Study on Rheological Properties of Bituminous Binders and Mixtures Containing Waste Printed Circuit Boards (PCBs) and SBR Compound Modified Bitumen

Improper handling of waste printed circuit boards (PCBs) can cause serious pollution to the water and soil environments. In order to explore a new method of recycling waste PCBs, this study investigated the effect of PCBs and butadiene styrene rubber (SBR) on the rheological properties of neat bitumen. The dynamic shear rheological (DSR) test was used to study the effect of different PCB contents on the high-temperature rheological properties of SBR-modified bitumen. Fluorescence microscopy and Fourier-transform infrared spectroscopy were used to study the microstructure change law and modification mechanism of PCB and SBR composite modified bitumen. Finally, the feasibility of the bitumen properties was verified through a test of the bituminous mixture properties. The DSR test results showed that the addition of PCBs improves the elastic recovery modulus, dynamic shear modulus, and rutting factor of SBR-modified bitumen, indicating that the high-temperature properties were improved. Infrared spectroscopy analysis revealed that a new absorption peak was generated in the infrared spectrum of the compound bitumen after the addition of PCBs, and the intensity of the original absorption peak also changed, indicating that PCBs and SBR-modified bitumen were mainly physically blended and accompanied by a weak chemical reaction. It was further found that the absorption peak of the unsaturated C=C double bond was significantly enhanced, and the increase in the content of the unsaturated bond C=C in the main chain of the polymer significantly increases the stiffness of the bitumen. Macroscopically, the high-temperature rutting resistance was improved to a certain extent. The fluorescence diagram shows that when PCBs do not exceed 10%, the PCBs can form a homogeneous structure and be dispersed in SBR-modified bitumen. The road test of PCBs and SBR composite modified bituminous mixtures showed that PCBs can significantly improve the rutting resistance and water stability of SBR-modified bitumen at high temperatures at the recommended optimum content. The crack resistance at low temperatures is weakened but still meets actual engineering requirements. The correlation analysis between the properties of bitumen and bituminous mixtures is carried out based on grey correlation theory. The results show that the index of modified bitumen has a very good guiding effect on the bituminous mixture properties. The development of PCBs and SBR composite-modified bitumen provides a new practical method for recycling waste PCBs.