## 1 Introduction
Several tests have concluded that the incorporation of recycled products (coarse aggregates) should not exceed 20% to preserve the properties of recycled concrete; this is a worldwide normative recommendation. In the case of fine material, although it is not regulated or is not allowed, scientific studies have shown that there is no alteration when it does not exceed 10% substitution and it can be improved with granulometric gradation in the addition of fine material generating greater cohesiveness [38; 52; 53; 54; 55; 56; 57; 58; 59]. Concrete is definitely one of the most versatile materials used in construction, as evidenced by the increase in its production in recent decades. It has great durability and strength, both of which are properties obtained by compaction. An alternative product is a self-compacting concrete (SSC), a two-phase material with improved properties that possess good fluidity and filling capacity around complex formwork and reinforcement. It can be cast into the formwork and consolidated by the application of weight without the need for external vibrations to achieve compaction. SSC is used to facilitate proper filling and structural performance of restrained and/or reinforced areas [60; 61]. This material possesses different characteristics from traditional concrete, for example, in terms of strength. The idea of this material was first introduced in 1992 by Okamura and has gained ground over time in the construction industry [60; 62; 63] due to the ease of placement in hard-to-reach areas with less effort and in less time [64]. Research and development in the construction industry have focused on evaluating techniques to improve the properties of self-compacted concrete, achieving higher performance in hardening, strength, durability, and surface quality [64; 65; 66]. The advantages of this type of material include technological, social, and economic advantages; however, its cost is two to three times higher than that of conventional concrete due to the high demand for cementations materials and chemical admixtures (superplasticizers or water reducers). In this sense, various mineral admixtures have been used, such as limestone, fly ash, and ground brick residues, to reduce costs and increase the slump of the concrete mix with the aim of improving mechanical properties. In this case, the deformability and cohesion, its durability, and the packing of the particles to obtain a decrease in permeability thus highlights the importance of making a proper selection of the aggregates to be used [67; 68; 69; 70]. In view of the concrete industry's high energy consumption due to the high demand for natural resources and the environmental risks it poses, recycled aggregates have been used as partial or full substitutes to minimize the environmental impact, taking a significant step towards establishing a sustainable society and boosting the circular economy [51; 71; 72]. Recycled aggregate is a type of composite material, the quality of which depends directly on the origin of the waste, the place and reason for demolition, and the original characteristics of the concrete [72]. Therefore, we should not lose sight of the fact that any change in the aggregate, no matter how small it may seem, will have a significant effect not only on the properties of the concrete but also on the cost of production, transportation, and commercialization. In this sense, several researchers have focused their studies on the use of recycled aggregates both coarse, in most cases, and fine [53; 59; 73; 74; 75]. The coarse recycled aggregate consists of two different materials: natural coarse aggregate and cement mortar bonded to the coarse aggregate (between 20-70%) [17]. [PERSON] et al. (2015) [67] observed that the fresh properties of self-compacting concrete with recycled aggregates could be maintained within EFNARC standards, although the compressive strength was found to be slightly lower than that of self-compacting concrete with normal aggregates.