عنوان مقاله [English]
The global environmental issues in recent century causes that recycling and using recycled materials became on the top of concentration in every sciences. The huge amount of fund that should be assigned for road construction and asphalt maintenance, difficulties on finding proper materials and limits on road projects budget causes highly attentions on using recycled asphalt mixtures. This study introduces using copper slag in cold-in-place recycled (CIR) asphalt mixtures as replacement material for fine aggregates. While using copper slag could be a great help for factories to make free of their production’s waste. Since the amount of copper slag which are produced by copper industries are significant in Iran and road projects contains a large volume of aggregates, using copper slag could results in economic production of asphalt and would be desirable for factories to save spaces of storing their wastes. In this research, copper slag has been introduced as aggregate for grading refinement of CIR asphalt mixture and feasibility of utilizing copper slag aggregates have been investigated. To reach this aim, a mixture of reclaimed asphalt pavement (RAP), copper slag aggregates and limestone aggregates with bitumen emulsion (in two types of anionic and cationic) have been used in this study. Properties of asphalt mixture such as Marshall Stability, durability, resilient modulus and permanent deformation were evaluated to find the effect of each additive on the properties of blends of mentioned recycled aggregates. According to the data obtained from Marshall Stability, indirect tensile strength and resilient modulus tests, using cooper slag as aggregates in CIR asphalt mixture results in better performance than mixtures containing limestone. Moreover, results of dynamic creep test indicates that mixtures containing copper slag as the coarse portion are more resistant to permanent deformation and caused a lower rut depth. In addition, a sample containing anionic bitumen emulsion shows better performance than samples made with cationic bitumen emulsion.