This study examines the mechanical and durability properties of five different concrete mixes using the construction and demolition waste as partial replacement of coarse aggregate. In the concrete mixes, a constant water–cement (w/c) ratio of 0.43 was used. In contrast, the natural coarse aggregates were replaced by recycled coarse aggregate using five different replacement percentages, i.e. 0 (R0), 30% (R30), 50% (R50), 70% (R70) and 100% (R100). The durability of recycled aggregate concrete (RAC) was investigated for 28, 90, 180, 365 and 720 days. The standard procedures were adopted for durability tests such as half-cell potential (ASTM C876), hydraulic permeability (DIN 1048) after exposure in salt spray machine, pull-out test (ASTM C900) and carbonation (CEN test). The results showed that the mechanical and durability properties of concrete with a replacement percentage of 0% and 30% are approximately similar. The comparative study of different replacement percentages showed that concrete with a 30% replacement percentage of natural coarse aggregate by recycled concrete aggregate can be used as structural concrete in the construction sector of Pakistan.

本研究使用建筑和拆除废物作为粗骨料的部分替代品，检查了五种不同混凝土混合物的机械和耐久性性能。在混凝土混合物中，使用了 0.43 的恒定水灰比 (w/c)。相比之下，天然粗骨料被再生粗骨料使用五种不同的替代百分比替代，即0（R0）、30%（R30）、50%（R50）、70%（R70）和100%（R100）。对再生骨料混凝土 (RAC) 的耐久性进行了 28、90、180、365 和 720 天的研究。采用标准程序进行耐久性测试，例如半电池电位 (ASTM C876)、盐雾机暴露后的透水率 (DIN 1048)、拔出测试 (ASTM C900) 和碳化 (CEN 测试)。结果表明，置换率为0%和30%的混凝土的力学性能和耐久性能基本相似。不同替代率的对比研究表明，用再生混凝土骨料替代天然粗骨料30%的混凝土可用作巴基斯坦建筑部门的结构混凝土。