## 1 Introduction  
An enormous hazard to the human ecological environment is posed by the destruction of obsolete buildings in China, which generates a lot of construction solid waste, of which concrete solid waste makes up around 40% [1]. Instead of natural coarse aggregate (NCA), many researchers have employed recycled coarse aggregate (RCA). The \"Standards for the Use of Recycled Aggregates and Recycled Aggregate Concrete\" were recommended by the Japan Construction Industry Association in 1977, and recycled aggregates and recycled aggregate concrete were defined in Chapter 4. When the replacement rate of the recycled coarse aggregate was 50%, the concrete's strength was enhanced by readjusting the aggregate's particle gradation. Additionally, there was an increase in diversity in concrete strength.  
In 1992, [PERSON] proposed a self-compacting concrete substance. Flow capacity (filling), passage capacity (fluidity), viscosity, and stability (resistance to segregation) are the characteristics of self-compacting concrete [2, 3, 4, 5, 6, 7]. The mechanical properties of recycled aggregate self-compacting concrete do not significantly alter when the percentage of recycled aggregate does not exceed 50% [8, 9, 10, 11]. Numerous studies have demonstrated that with the right replacement ratio, recycled coarse aggregate self-compacting concrete (RCASCC)can perform better than standard self-compacting concrete in terms of workability and fundamental mechanical properties [12; 13; 14; 15; 16]. Thus, it is possible to use RCASCC.  
Sulfate ions have the potential to seriously harm concrete structures. Gypsum and calcium sulfo-aluminate are produced when sulfates react with the calcium silicate hydrated (C-S-H) gel, expanding in volume and causing surface cracking or softening. Additionally, cracks facilitate the infiltration of corrosive water containing sulfate and other ions, which speeds up the decomposition of the concrete. Cracks also damage the cement hydrates' bonding characteristics, which significantly reduces the durability of concrete [17]. Recent studies have looked at recycled concrete with coarse particles' resilience to sulfate. While the results vary, they all demonstrate that high replacement rates lower a material's resistance to sulfate attack. These investigations used recycled aggregates with various compositions as well as various substitution rates and erosion settings [17]. Despite substantial research on the mechanical and durability characteristics of SCC produced using RCA, only a small number of studies have specifically focused on these characteristics [18].  
Many locations in Xinjiang are salty, and salty soil includes a variety of hazardous ions, the most prevalent of which are sulfate ions [19]. Few investigations on the dry and wet sulfate cycle erosion of recycled aggregate self-compacting concrete have been carried out thus far. The current study expands on previous research by examining the impact of recycled aggregate self-compacting concrete's sulfate resistance in order to provide some reference indices for its practical implementation [9]. A reference index for the creation of requirements for self-compacting concrete with recycled aggregate is another goal of the project. Additionally, it serves as a reference for the creation of self-compacting concrete requirements [20]. By integrating experimental approaches and theoretical analysis, the damage process and degradation mechanism of self-compacting concrete with RCA during a dry-wet cycle and linked sulfate erosion are explored [14].