Effect of recycled concrete agregate on properties of roller compacted concrete

In recent years urban renewal programs implemented huge concrete waste in Turkey. Using these wastes as recycled aggregate in roller compacted concrete (RCC) is one of the possibilities to reduce large amount of them. The object of this thesis is using recycled aggregate in roller compacted concrete. For this purpose 150, 200 and 250 kg/m3 cement dosage were chosen as the binder in RCC mixtures. In all of the mixtures 0%, 25%, 50%, 75% and 100% by weıght of crushed coarse limestone aggregate was replaced wıth recycled concrete aggregate. Water/cement ratios were find by experimental studies and 15 RCC mixtures were prepared. The compressive strength, splitting tensile strength and drop weight impact tests were applied to assess the mechanical properties and water absorption, capillary absorption, permeability, freeze-thaw resistance and superficial abrasion tests were applied to obtain the durability characteristics of the mixtures. The results showed that increasing the amount of recycled aggregate decreased both the mechanical properties and durability characteristics of concrete. However up to 25% replacement level, recycled aggregate had not a significant detrimental effect on the properties of concrete. Besides, the detrimental effect of RCC substitution reduced by increasing the cement content of the mixtures. Keywords: Roller compacted concrete, recycled aggregate, cement dosages, optimum water content, mechanical properties, durability