## 1 Introduction  
Concrete materials have become the second most-consumed type of material in the world [1]. Due to the considerable annual demand for concrete and aggregate, the supply of these materials in the near future is suspect. The global demand for construction aggregates is estimated to increase by 5.2%, annually, to 48.3 billion tons, until 2020. A large percentage of the global aggregate supply (approximately 67%, in 2015) is consumed in Asia-Pacific countries. The sustainable development of these materials relies on the judicious use of natural resources. The use of recycled aggregate from crushed concrete waste, for the production of new concrete, is one alternative offering an effective green solution by prolonging the lifespan of natural aggregate. Although the advantages of recycled aggregate are widely recognized, its applications remain limited. Several researchers have investigated the effects of recycled aggregate on the properties and behavior of concrete. For example, several authors investigated the effect of the parent concrete properties on the properties of recycled aggregate concrete [2; 3]. [PERSON] et al. [4] investigated concrete made with fine and coarse aggregates recycled from fresh concrete waste. [PERSON] et al. [5] investigated the effect of aggregate type on the compressive strength of concrete. The weaknesses and mortar content of recycled aggregate depend on the type, size, and strength of the natural aggregate, as well as the parent concrete strength, crusher types, and crushing processes. A parent concrete of a higher strength creates a stronger mortar and a better bond between the mortar and the natural aggregate, leading to improvements in the properties of the recycled aggregate concrete. However, the higher mortar content could have greater negative effects on the recycled aggregate concrete properties. It is extremely difficult to obtain information on the recycled aggregate, parent concrete, and aggregate production from recycling factories because concrete waste is typically obtained from a variety of sources. Therefore, another approach should be developed to more widely understand and control the effects of recycled aggregate quality on concrete properties. Such an approach would expand the application of recycled aggregate concrete in structural concrete members. [PERSON] et al. [6] proposed the study of stress-strain behavior of the fiber-reinforced plastic (FRP)-confined recycled aggregate concrete. The effects of replacement by recycled coarse aggregate, on the axial and the lateral strain of a concrete cylinder, were examined. The experimental results show that the specimens that use 20% replacement, by a coarse, recycled aggregate, behave similarly to that of normal concrete but specimens that use a 100% replacement show a lower strength and significantly different stress-strain response. [PERSON] et al. [7] investigated the mechanical behaviors of recycled aggregate, under a tri-axial compression of the FRP-confined column; the influence of a recycled aggregate content and its source were also examined. In the field of civil engineering, concrete is always reinforced with steel rebar, and the bond strength and interacting behaviors between the concrete and steel rebar are among the most important requirements of reinforced concrete (RC) design and construction. The bond behavior of concrete is controlled by the concrete type, rebar arrangement, loading conditions, and construction details [8]. The bonding strength between natural and recycled aggregate concrete and rebar are similar, although the compressive strength exhibits a downward trend with increases in the recycled coarse aggregate replacement ratio [9]. [PERSON] and [PERSON] [10] presented a model for predicting crack-width on the basis of bond stress, with different reinforcement amounts and concrete strength. It was confirmed that the effect of reinforcement amounts on the crack-width was significant.