The use of recycled aggregate (RA) to produce recycled aggregate concrete (RAC) is a proven way of decreasing the consumption of natural aggregate (NA) and the landfilling of construction and demolition waste. However, adoption of codes for the design of RAC and RAC structures has been lacking. Within the framework of the new fib Model Code 2020 and Eurocode 2, provisions for RAC can be adopted. Therefore, in this study, a comprehensive and critical review of literature on RAC is performed as well as own meta-analyses of results. Material properties of RAC and structural behavior of reinforced and prestressed RAC members are analyzed, and based on the findings, code adjustments for RAC are proposed. The results show that, in order to incorporate RAC into design codes, changes are necessary in expressions for physical–mechanical properties (volumetric mass, modulus of elasticity, tensile strength, fracture energy, peak and ultimate strains, shrinkage strain and creep coefficient), durability-related properties (minimum concrete cover for durability) and structural behavior (shear strength of members not requiring shear reinforcement and deflections). The recommendations are formulated in terms of the total mass substitution ratio of RA that can be classified as Type A according to standard EN 206 for concrete. The results and findings presented herein can provide an important contribution toward the codification of RAC use and the wider utilization of RA in construction.

中文翻译：

---

实现再生骨料混凝土结构的规范化设计：新 fib 模型代码 2020 和欧洲规范 2 的背景

使用再生骨料 (RA) 生产再生骨料混凝土 (RAC) 是一种行之有效的减少天然骨料 (NA) 消耗和建筑和拆除废物填埋的方法。但是，一直缺乏用于 RAC 和 RAC 结构设计的代码的采用。在新的fib框架内模型代码 2020 和欧洲规范 2，可以采用 RAC 的规定。因此，在这项研究中，对 RAC 的文献进行了全面和批判性的审查，并对结果进行了自己的荟萃分析。分析了 RAC 的材料特性以及加强和预应力 RAC 构件的结构行为，并根据研究结果提出了 RAC 的规范调整。结果表明，为了将 RAC 纳入设计规范，必须改变物理机械特性的表达式（体积质量、弹性模量、拉伸强度、断裂能、峰值和极限应变、收缩应变和蠕变系数），与耐久性相关的特性（用于耐久性的最小混凝土覆盖层）和结构行为（不需要剪切钢筋和挠度的构件的剪切强度）。这些建议是根据 RA 的总质量替代比制定的，根据混凝土标准 EN 206 可将其归类为 A 类。本文提出的结果和发现可以为 RAC 使用的编纂和 RA 在建筑中的更广泛应用做出重要贡献。