To facilitate an accurate and rapid characterization of the dynamic modulus of rubber reinforced asphalt mixture, experimentation is here combined with advanced computational homogenization to conduct a series of analyses. First, the dynamic moduli of pure and waste rubber modified asphalt mixtures are obtained experimentally. Subsequently, meso-structure digital twins are generated in MATLAB, and the viscoelastic parameters of the mastic are deduced and verified through dynamic modulus simulations using 2D and 3D homogeneous models subjected to sinusoidal loading. Third, the mixtures are simulated in Abaqus using a novel elastic displacement load approach, which enables significantly faster but still accurate analyses. The results indicate the enhanced deformation resistance of waste rubber mixtures. Numerical results of the virtual mixtures at various temperatures closely match the experimental ones. In parallel, test windows with five different sizes are extracted from five locations of the original model, having an insight into errors introduced by scaling sizes and changing constraint conditions. The proposed elastic displacement load method can provide dynamic moduli rapidly and accurately, demonstrating agreement with the sinusoidal displacement load approach. The 2/3 and 1/2 scaled models, sampled in different locations, proved good predictivity, differently from 1/3, 1/4, and 1/5 ones, characterized by expected increasing errors. The influence of loading constraints on the simulation results is finally underscored by discussing both the dynamic modulus and displacement/stress contours.

In this study, the effects of waste chopped basalt fiber (WCBF) and waste chopped polyester fiber (WCPF), along with their characteristic parameters, on the mechanical properties and crack resistance of recycled aggregate asphalt mixture (RAAM) were systematically studied. The research aims to enhance pavement service life while reducing reliance on non-renewable resources and minimizing environmental impact. The key pavement performance indicators, including rutting resistance, low-temperature crack resistance, and water stability were evaluated. Semi-circular bending (SCB) tests, digital image correlation (DIC), and crack resistance (R-curve) analysis were employed to quantify fracture behavior and energy dissipation. A comprehensive life cycle assessment (LCA) was conducted to quantify the associated environmental impacts. The results show that the incorporation of fibers significantly improves the crack resistance of RAAM, and WCBF modification is generally superior to WCPF with the same characteristic parameters. The superior performance of WCBF over WCPF is attributed to its higher tensile strength and better interfacial adhesion with the asphalt matrix, which facilitated more effective stress transfer and crack bridging. Compared with the control group, the waste chopped basalt fiber with a length of 6 mm and a diameter of 7 mu m (BF-6-7) shows the best performance, the dynamic stability is increased by 92.9 %, fracture energy increased by 48.8 %, and flexibility index increased by 135.5 %. Fracture analysis revealed that fibers increased crack tortuosity, delayed propagation via bridging effects, and dissipated energy through pull-out or fracture. LCA results revealed that the BF-6-7 mixture reduced global warming potential and energy consumption by 15.5 % and 12.4 % per ton, respectively. Within the LCA framework, based on a model that translates improvements in fracture energy into an extension of service life, the assessment results show that service life is extended by 35 %, maintenance frequency is reduced by 40 %, and 82 % of the total emission reduction is achieved. This study provides mechanistic insights into the crack resistance of fiberreinforced RAAM and establishes a quantifiable environmental basis for selecting optimal fiber parameters. These findings support the synergistic use of waste materials and promote sustainable pavement engineering.

Phase change materials (PCMs) have been recognized as promising materials for thermoregulation in asphalt pavements. To improve the thermoregulation range and efficiency, two polyethylene glycols with different molecular weights (PEG2000 and PEG10000) were absorbed into the treated diatomite powder via vacuum adsorption to prepare the binary shape-stabilized composite PCMs (the PCMs). The diatomite powder was modified through a combined process of calcination, microwave irradiation, and acid–base treatment. The thermoregulation performance and properties of asphalt binders incorporating the PCMs were evaluated through a series of laboratory tests. Results indicate that the combined treatment significantly increases the diatomite total pore volume from 0.475cm³/g to 0.766cm³/g and its specific surface area from 30.2350m²/g to 71.1170m²/g. The PCMs with the mass ratio mPEG2000:mPEG10000 = 4:6 enables precise regulation of the phase change temperature within the range of 48.40℃-64.85℃, with corresponding latent heat values ranging from 180.52J/g to 199.88J/g. At a PCMs content of 20%, the temperature rise rate of the asphalt binder decreased by 41.3% while that within the phase transition plateau was reduced by as much as 62%, indicating a significant thermoregulation effect. The incorporation of the PCMs increases the softening point, viscosity, rutting factor, and creep stiffness of asphalt binders. Nevertheless, it compromises the low-temperature performance, as evidenced by decreased ductility and a lower penetration index. The appropriate content of the PCMs should be determined by balancing high- and low-temperature performance according to practical requirements.

This study systematically investigates the synergistic effects and mechanisms of waste-chopped basalt fiber (WCBF) with varying characteristic parameters (lengths: 3, 6, 12 mm; diameters: 7, 16, 25 mu m) on asphalt mixture (AM) performance across high, medium and low-temperature domains. The primary objective is to establish a quantitative relationship between the characteristic properties (length and diameter) of WCBF and the multi-temperature performance of basalt fiber reinforced asphalt mixture (BFAM), thereby optimizing the fiber characteristic parameters to achieve sustainable pavement applications. Uniaxial dynamic creep tests, direct tensile cyclic fatigue tests, and thermal stress-restrained sample tests were employed to evaluate hightemperature deformation resistance, intermediate-temperature fatigue behavior, and low-temperature crack resistance. Dynamic modulus analysis and equal cross-section theory were further applied to elucidate the synergistic mechanisms. The results indicate that the characteristic parameters of WCBF consistently influence the asphalt mixture across diverse temperature domains. When the fiber diameter remains constant, the performance of BFAM exhibits an initial increase followed by a subsequent decrease with increasing fiber length. Conversely, when the fiber length is fixed, a decrease in performance is observed with an increase in fiber diameter. The optimal performance of the asphalt mixture when blended with BF-6-7 was observed across all temperature domains. The characteristic parameters of the fibers directly affect the monofilament dispersion and interfacial adhesion regulated by the specific surface area, the formation of the stress transfer spatial network, and the proportional regulation of the viscoelastic components, which are the main factors affecting the performance of AM. Notably, smaller diameters maximized the cross-sectional moment of inertia, while intermediate lengths balanced fiber-asphalt interactions and defect minimization. This paper reuses waste-chopped basalt fibers by changing their characteristic parameters, and the modification effect and mechanism of fiber characteristic parameters on the performance of asphalt mixtures were studied, providing ideas and technical references for the efficient utilization of WCBF.

Ecological river slope protection techniques have received considerable attention for sustainable development. This study focuses on a newly developed material called cast-in-situ vegetation concrete (CVC), which incorporates vegetation and punched holes. A series of anti-scouring tests were conducted to optimize its construction parameters. Wave scouring tests on bare slopes and rainfall scouring tests on vegetated slopes were carried out to evaluate the effects of flow velocity, rainfall intensity, slope gradient, punched hole parameters, and construction thickness on underlying soil erosion. Additionally, high-flow scouring tests were conducted to examine the overall survival status of vegetation after scouring under different construction thicknesses and perforation parameters. The results indicate that flow velocity, rainfall intensity, and slope gradient are positively correlated with soil erosion. Among these, Perforation Group A (4.5 cm in depth, 2.5 cm in diameter, 2.8 cm in spacing) demonstrated superior performance to Perforation Group B (4.0 cm in depth, 1.0 cm in diameter, 3.5 cm in spacing), exhibiting lower erosion volume and better vegetation-reinforced slope protection effects. In terms of promoting stable vegetation survival, construction thicknesses of 6 cm or 10 cm were found to be preferable to 15 cm. Therefore, the parameters of Perforation Group A with a thickness of 6 cm or 10 cm are recommended. These findings offer practical guidance for the application of Cast-in-place Vegetation Concrete (CVC) technology in ecological slope protection.

To quantitatively evaluate the influence of asphalt migration on skid resistance degradation, this study investigated an SBS-modified asphalt SMA-13 mixture under selected temperature-load combinations. Accelerated loading abrasion tests, layered extraction tests, British Pendulum Number (BPN) tests, and Mean Texture Depth (MTD) tests were conducted. The evolution of asphalt migration, BPN, and MTD during abrasion was then characterized. The results show that both temperature and load promoted asphalt migration toward the surface layer. Increasing temperature had a more pronounced effect on asphalt migration and BPN loss. BPN increased during the initial abrasion stage and entered a degradation stage after 5,000 cycles. In contrast, MTD continuously decreased, while asphalt migration continuously increased with abrasion cycles. Taking 5,000 cycles as the baseline, the asphalt migration increment showed strong positive correlations with both BPN loss and MTD loss. Within the tested range, every 0.1% increase in asphalt migration increment corresponded to an average BPN loss of approximately 2.95 and an MTD loss of approximately 0.030 mm. The positive correlation between MTD loss and BPN loss indicates that macro-texture loss is an important pathway linking asphalt migration to skid resistance degradation. Furthermore, the migration-associated loss ratio increased with abrasion cycles. At 50,000 cycles, the average BPN migration-associated loss ratio and MTD migration-associated loss ratio reached 70.7% and 66.8%, respectively. These results indicate that asphalt migration had a stronger explanatory effect on BPN loss and MTD loss in the middle-to-late abrasion stage. These findings provide a reference for improving the skid resistance durability of asphalt pavements by considering asphalt migration and macro-texture degradation.

Polyurethane Porous Elastic Mixture (PUPEM), also known as Poroelastic Road Surface (PERS). PUPEM is an innovative material that effectively improves pavement durability, reduces traffic noise and simultaneously utilizes waste rubbers. However, there is a lack of systematic investigation on the performances, void structure characteristics, long-term sound absorption mechanism and their relationships for PUPEM. For these purposes, the performances of PUPEM were evaluated through wheel-tracking tests, low-temperature bending tests, immersion Marshall tests, freeze-thaw splitting tests, Cantabro loss tests, and binder drainage tests. The characteristics of void structure were extracted and analyzed by the computer tomography scanning system. Specimens subjected to void-clogging and thermo-oxidative aging were prepared to evaluate the long-term sound absorption performance of PUPEM. Results indicate that PUPEM has excellent high-temperature stability, good low-temperature cracking resistance, and the satisfied water stability. The gradation with larger interconnected voids exhibits superior sound absorption, particularly in the low-frequency range. Void clogging has a pronounced impact on sound absorption performance, while the effect of thermo-oxidative aging is comparatively minor. Additionally, the maximum sound absorption coefficient is predominantly determined by the total void volume, fractal dimension, and reconstructed porosity. A predictive model for the sound absorption coefficient, incorporating total void volume, fractal dimension, and reconstructed porosity, was established through correlation analysis. This model offers meaningful insights for advancing the research and application of polyurethane porous elastic mixtures in sound absorption.

Asphalt pavements offer significant potential for the large-scale reuse of recycled concrete aggregates (RCA). However, the porous adhered mortar of RCA introduces some defects in the aggregate-asphalt interfacial transition zones (ITZ), which weaken the performance of asphalt mixture. Considering the limitations of individual treatments in enhancing the comprehensive properties of RCA, a gas treatment (COQ carbonation), a liquid treatment (tetraethyl orthosilicate silicification), and the gas-liquid combined treatment were conducted and compared in this study. Systematic evaluations were further carried out on the influence of above treatments on RCA, asphalt mixtures incorporating RCA, and their ITZ. Results demonstrate that the carbonation-silicification treatment leads to a 75% reduction in the water absorption, a 30.02% decrease in the crushing value, a 43.97% decrease in the Los Angeles abrasion value, a 10.32% reduction in the alkali content, and a 67.31% improvement in soundness. These changes imply aggregate strength that approaches that of natural aggregates, reduced porosity, and decreased adhesion to asphalt. Consequently, the asphalt mixtures incorporating RCA exhibit a 10.87% reduction in asphalt-aggregate ratio, a 38.18% decrease in dynamic stability, a 46.77% increase in lowtemperature failure strain, and a slight decrease in moisture-damage resistance, representing a normalization of their performance toward that of asphalt mixtures with natural aggregates. At the microscopic level, the average peak of the pore size distribution curve of RCA decreases by 82.2%, the critical pore diameter decreases by 48.96%, and the silicon calcium ratio of the ITZ declines by 12.71%. The combined treatment densifies the internal pores and seals the surface pores of RCA, improves the smoothness of the interface between the adhered mortar and the asphalt mastic, and increases the proportion of strength-related compounds of ITZ. These findings validate the effectiveness of the gas-liquid combined treatment in enhancing the properties of RCA for asphalt pavements.

The interface behavior largely determines the mechanical response of fiber-reinforced asphalt mixtures. However, accurately identifying and characterizing the interface transition zone (ITZ) and its physicochemical properties still pose challenges. To investigate the ITZ and interactions of the fiber-asphalt mastic-aggregate, Fourier-transform infrared (FTIR) spectroscopy was utilized for analyzing the physical-chemical interaction mechanisms, while scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS) was employed to identify and quantify the extent of the ITZs. Then the relationship between the ITZs and the interfacial bonding performance was discussed. The results indicate that the addition of fibers or aggregates does not result in significant chemical bonding, primarily relying on physical adsorption. The carbon, silicon, and oxygen elements are effective in identifying the ITZs between the inorganic fibers and asphalt mastics, whereas sulfur element exhibits a more pronounced presence in the polyester fiber-asphalt mastic interface. The ITZ width between the fibers and asphalt mastics is approximately 3.3-5.9 mu m, with the polyester fiber -asphalt mastic exhibiting the greatest thickness at 5.9 mu m. Notably, silicon/calcium element is prominent in the identification of the ITZs among the aggregate-asphalt mastics, with widths ranging from 29 to 37 mu m, and the limestone-asphalt mastic ITZ is the widest at 36.3 mu m. The width of the ITZ is not completely positively correlated with the interfacial bonding performance. Rather, it is also influenced by the intrinsic properties of the twophase materials. This study offers a robust methodology for the quantitative analysis of the transition zone at the fiber-asphalt-aggregate interface, establishing a foundation for further comprehensive research.

The increasing generation of construction and demolition waste (CDW) and the overexploitation of natural aggregates (NA) have necessitated sustainable solutions for recycled aggregate concrete (RAC). This study proposes an innovative inorganic-organic combined modification method using water glass (WG) and sodium methyl silicate (SMS) to enhance the performance of recycled coarse aggregate (RCA) and RAC. A comprehensive experimental program was conducted, including crushing value tests, capillary water absorption, compressive and splitting tensile strength analysis, nanoindentation and Fourier transform infrared spectroscopy (FTIR). The results demonstrated that the combined treatment of 40% WG and 10% SMS significantly improved the RCA properties, reducing water absorption by up to 46.47% and increasing the compressive strength of the RAC by 34.8%. Through mechanistic analysis, it was found that after treatment with SMS solution, a hydrophobic film formed on the surface of the RCA, thereby preventing the transmission of moisture. The interface transition zone between the RCA and the new cement mortar was enhanced, consequently improving the mechanical properties of the RAC. This study contributes to improving the properties of recycled aggregate and recycled aggregate concrete, and to the understanding of the mechanism of combined modification.

The diameter of basalt fiber influences the reinforcement of basalt fiber asphalt mixtures. However, the performance evaluation and mechanistic analysis of asphalt mixtures reinforced with varying fiber diameters have been insufficiently studied. AC-13 asphalt mixtures were designed and prepared with four different fiber diameters 7 μm, 16 μm, 25 μm, and an equal-mass mixture of these. The reinforcement mechanisms were analyzed using the equal cross-section theory. Results indicate that the incorporation of 7 μm and mixed-diameter basalt fibers significantly enhances the pavement performance of the asphalt mixtures compared to the control group without fibers. Additionally, it is shown by triaxial shear tests that the cohesion of the asphalt mixtures with the aforementioned two diameters of basalt fibers is strengthened by 61.5% and 55.5%, respectively. The dynamic modulus values in the high-frequency range are found to be positively correlated with fiber diameters. Since the fiber mass content and modulus were held constant, a decrease in diameter was observed to lead to an increase in fiber quantity. This is manifested by a multiple-fold increase in the total transformed cross-section (TTCR) index for 7 μm fiber asphalt mixtures, as described by the equal cross-section theory. It is concluded that the performance improvement of the asphalt mixtures can be further enhanced under the same fiber content and cost conditions by optimizing diameter parameters.

The use of crumb rubber (CR) derived from waste tires in bitumen for paving offers significant benefits, including the enhancement of pavement durability and a reduction in the environmental issues associated with tire waste. The aim of this study is to investigate the rheological properties of high-cured crumb rubber-modified bitumen (HCRMB) after aging. Results indicate that HCRMB has better fatigue resistance and low-temperature stress relaxation performance compared to neat bitumen, and a higher CR content results in a more obvious improvement in low temperature and aging resistance. Under unaged conditions, elevating the CR content could deteriorate the compatibility of HCRMB. Furthermore, there is a continuous interaction between CR desulfurization, polymer degradation, and neat bitumen age-hardening in HCRMB, resulting in a nonlinear trend of the rheological indices with CR desulfurization level and polymer degradation level during aging.

Incorporating fiber stabilizers into warm mix asphalt (WMA) to enhance the performance has been a significant subject, which facilitates the realization of green road paving and extends the durability of asphalt pavements. This study emphasizes the potential of basalt fibers as a promising additive for WMA materials. The rheological properties of WMA binders were examined by dynamic shear rheometer, multiple stress creep recovery, and bending beam rheometer tests, along with the influence of basalt fibers on the microstructure and composition of WMA binders through atomic force microscopy and Fourier transform infrared spectroscopy. Subsequently, the construction workability and pavement performance of basalt-fiber-reinforced WMA mixtures were analyzed by conventional asphalt mixture tests. The results indicated that sufficient heating and mixing resulted in a modest increase in the viscosity of the WMA binder containing 6% Aspha-min. There were not significant chemical reactions between the four WMA binders and basalt fibers, but the mixing caused noticeable changes in surface structure and morphology of asphalt binders. Notably, Energy Champion 120 had the most significant influence on the component structure of asphalt binders, nearly eliminating the "bee-like" structure. The introduction of basalt fibers led to a slight increase in both mixing and compaction temperatures. Additionally, all four additives had an adverse effect on the water damage resistance performance of asphalt mixtures, and none of them was able to enhance the properties associated with both high and low temperatures. Through comprehensive evaluation and analysis, basalt fiber has a significant enhancement effect on the comprehensive performance of the WMA mixtures.

Recycled concrete aggregates (RCAs) produced by crushing the demolished concrete from construction and demolition waste (C&DW) are potential raw materials for sustainable asphalt pavement, providing an alternative method to facilitate the efficient use of C&DW. However, the deterioration of RCAs brings risks to the load-bearing capacity of the aggregate skeleton of asphalt mixture. This study aims to investigate the mechanical properties, especially the crack propagation behaviors of asphalt mixtures containing RCAs (AM-RCAs). For this purpose, dense graded asphalt mixtures with RCAs replacement proportions of 0, 17, 37, and 56.7 % were designed and prepared for performance tests, including high-temperature rutting tests, low-temperature small beam tests, water immersion Marshall tests, freeze-thaw splitting tests, uniaxial penetration tests, indirect tensile asphalt-cracking tests, semi-circular bending tests, and dynamic creep tests. Digital image correlation (DIC) was synchronized with the semi-circular bending test to record the entire crack propagation process of the AM-RCAs. Depending on the replacement proportions of RCA, AM-RCAs exhibit a higher asphalt-aggregate ratio and improved high-temperature stability and water stability, but sharply decreased cracking resistance. With the increase of the RCAs replacement proportions, the CTIndex values decrease by 32.9, 31.6, and 38.4 %, respectively; the W-fb values decrease by 6.95, 9.75, and 11.28 %, respectively; the G(f )values decrease by 22.4, 23.1, and 30.5 %, respectively; and the FI values decrease by 16.6, 17.5, and 42.9 %, respectively. DIC analysis indicates that the areas prone to cracking along the crack propagation paths of the specimens are the RCAs-adhered mortars and their interfaces with asphalt binders, emphasizing the necessity of strengthening treatments of RCAs. The average crack-propagation rate of AM-RCAs increases by more than 7.3 %, and the fracture toughness decreases by more than 3.9 %, indicating that AM-RCAs are more prone to cracking than asphalt mixtures using natural aggregates (AM-NAs). These findings provide a visual and quantitative method for evaluating the crack propagation behavior of AM-RCAs.

Despite advancements in bitumen technology, traditional bitumen often fails to meet the increasing demands for durability and environmental sustainability. In this study, thermoplastic polyurethane (TPU) and waste rubber powder (WRP) were utilized to prepare a composite-modified bitumen to overcome the performance limitations of conventional bitumen. The performance of this composite-modified bitumen was comprehensively evaluated through rheological tests, thermal stability tests, infrared spectroscopy, and micro-morphological analysis. Molecular dynamics simulations revealed the molecular-level interactions between TPU and WRP, further explaining the enhancement mechanisms. The study showed that WRP undergoes a crosslinking reaction at high temperatures, enhancing the thermal stability of the composite-modified bitumen, while the elasticity of TPU promotes a microlevel interlocking mechanism that improves mechanical properties and deformation resistance. The optimal mixing ratios of TPU to WRP were determined to be 8 % and 10 %. The three-dimensional network structure formed by the long polymer chains of TPU as the main framework, interspersed with WRP, effectively optimizes the temperature stability and elastic recovery of the bitumen. This study not only fills a critical gap in research on the synergistic effects of TPU and WRP but also provides a theoretical and experimental foundation for developing low-noise, durable bitumen pavements.

Asphalt is a kind of high viscosity material with fluidity under certain conditions, which results in the healing function to repair small cracks of asphalt pavement by itself, and thus prolonging the service life of the pavement. With the aging process, the flow behavior of asphalt will gradually deteriorate and synchronously impact the self-healing performance. To gain a deeper understanding of the changes in asphalt's performance characteristics after aging, Fourier transform infrared spectroscopy tests, Frequency scanning tests, and Fatigue-healing-fatigue tests were conducted to examine the changes in flow behavior and self-healing properties of asphalt enduring secondary aging. The results showed that SBS modified asphalt presented superior anti-aging performance compared to base asphalt, since the SBS modifier can effectively prevent the formation of sulfoxides and carbonyl groups in asphalt. However, SBS modifier will also inhibit the flow behavior of asphalt due to its complex three-dimensional spatial structure, leading to a decrease in flow behavior index from 0.967 for unaged base asphalt to 0.672 for SBS modified asphalt, respectively. Furthermore, both of the flow behavior and self-healing performance will be affected by aging process. After secondary aging, the flow behavior index of base and SBS modified asphalt decreased by 9.8% and 12.1% compared to the corresponding virgin asphalt mastics, respectively, while the self-healing performance decreasing by 83.9% and 57.6%. These findings provide an innovative perspective for secondary recycling research and application of asphalt pavements.

This study examines the impact of incorporating a high content of waste tire rubber into bitumen on its aging behavior, utilizing the terminal blend method. The binders were subjected to both thermal oxidative and weathering aging processes. To assess their chemo-rheological behavior before and after aging, a series of tests were performed, including gel permeation chromatography (GPC), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), temperature sweep analysis, rheological master curve evaluation, and multiple stress creep recovery tests. Additionally, the morphological changes were observed using fluorescence microscopy. GPC and ATR-FTIR observations show that during the aging process of high-content terminal blend rubber modified bitumen (HCTBMB), the crumb rubber (CR) desulfurization and the polymer degradation process occur simultaneously. In the short-term aging stage, the CR desulfurization behavior dominates, and as aging progresses, polymer degradation becomes more significant, surpassing CR desulfurization. Besides, as aging progresses further, HCTBMB initially softens during short-term aging but becomes harder in the long-term aging phase. Additionally, this transition is accompanied by the degradation of some high-molecular polymers into medium and small molecular-weight polymers. After extended aging, polymer particles are nearly absent in the HCTBMB, which exhibits superior anti-aging properties compared to the base bitumen. Moreover, the oxidation level strongly influences the complex modulus, and the extent of CR desulfurization is influenced by the CR content, which in turn significantly affects the proportion of both macromolecular and medium molecular polymers.

The poor quality of recycled coarse aggregate (RCA), particularly its high water absorption and low strength, has long restricted the development of recycled aggregate concrete (RAC). In this study, a novel combined spraying treatment method integrating cement slurry and a methyl sodium silicate (MSS) solution was proposed to improve the comprehensive performance of RCA. The effects of the treatment on RCA properties, including crushing value, water absorption, dynamic water absorption, apparent density, micromorphology, and contact angle, were systematically investigated. Furthermore, the treated RCA was incorporated into concrete to evaluate the mechanical strength, water absorption, and interfacial transition zone (ITZ) properties of the resulting RAC. The results indicated that cement slurry treatment alone significantly reduced the crushing value of the RCA by 30.1% but had little effect on water absorption. Conversely, MSS solution treatment reduced RCA water absorption by 29.6% without affecting its strength. The combined spraying method successfully enhanced both strength and water absorption performance. When applied in the RAC, cement slurry-treated RCA improved compressive and splitting tensile strengths, while MSS-treated RCA notably reduced water absorption. RAC prepared with combined-treated RCA achieved further strength improvement, and although its water absorption was not as low as that of MSS-only treated RAC, it still showed a substantial decrease compared to untreated RCA. Nanoindentation and microstructural analyses revealed that MSS enhanced the ITZ by forming a hydrophobic molecular film and reacting with new mortar, inhibiting water transport and improving RAC durability. An optimal MSS concentration of 10% was identified for achieving the best combined performance in strength and durability.