صدرا سقائي

Cold recycled asphalt mixtures (CRAM) have attracted significant attention as a sustainable approach for rehabilitating deteriorated pavements due to their energy efficiency, reduced consumption of natural resources, an‎d lower environmental impacts. However, their mechanical performance, moisture susceptibility, an‎d tendency to crack at low temperatures have limited their widespread application. In this study, laboratory-prepared mixtures were produced using reclaimed asphalt pavement (RAP), new dolomitic aggregates, an‎d a cationic slow-setting emulsion (CSS-1). The objective was to eva‎luate the effect of micronized silicon carbide (SiC) powder at various contents (0.5%, 1%, 1.5%, 2%, an‎d 2.5% by weight of binder) on the functional properties of cold recycled asphalt mixtures. The performance of the mixtures was assessed through moisture susceptibility, dynamic creep, semicircular bending (SCB) tests under Modes I an‎d II, crack resistance index (CRI), an‎d healing index (HI) at three temperatures: 0°C, −12°C, an‎d −24°C. Statistical analysis of variance (ANOVA) was performed at a 95% confidence level to determine the significance of the observed variations. The results indicated that the maximum improvement in moisture resistance occurred in the mixture containing 1.5% SiC, showing an approximately 7.6% increase compared with the control sample. In the dynamic creep test, the best performance was observed at 2% SiC, exhibiting a 76% improvement over the control mixture. Furthermore, SiC addition enhanced fracture resistance, crack propagation resistance, an‎d low-temperature CRI values. The healing index (HI) of samples with 2% SiC improved by approximately 16–38% relative to the control. Overall, these findings demonstrate that incorporating up to 2% SiC powder can simultaneously improve the moisture resistance, mechanical strength, crack resistance, an‎d self-healing capability of cold recycled asphalt mixtures, offering an effective strategy for extending the service life of aged pavements.

مخلوط آسفالتي بازيافت سرد , پودر سيليكون كاربيد , انرژي شكست , شاخص خودترميمي , تحليل آماري واريانس

Cold recycled asphalt mixture , Silicon Carbide powder , Fracture Energy , Healing index , Analysis of Variance (ANOVA)

SadraSaghaei

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