Santos Sara A, da Silva Pedro R, de Brito Jorge
Civil Engineering Master, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisbon, Portugal.
CERIS, Instituto Superior de Engenharia de Lisboa, Instituto Politécnico de Lisboa, 1959-007 Lisbon, Portugal.
Materials (Basel). 2017 Aug 4;10(8):904. doi: 10.3390/ma10080904.
This paper intends to evaluate the feasibility of reintroducing recycled concrete aggregates in the precast industry. The mechanical properties of self-compacting concrete (SCC) with incorporation of recycled aggregates (RA) (coarse recycled aggregates (CRA) and fine recycled aggregates (FRA)) from crushed precast elements were evaluated. The goal was to evaluate the ability of producing SCC with a minimum pre-established performance in terms of mechanical strength, incorporating variable ratios of RA (FRA/CRA%: 0/0%, 25/25%, 50/50%, 0/100% and 100/0%) produced from precast source concretes with similar target performances. This replication in SCC was made for two strength classes (45 MPa and 65 MPa), with the intention of obtaining as final result concrete with recycled aggregates whose characteristics are compatible with those of a SCC with natural aggregates in terms of workability and mechanical strength. The results enabled conclusions to be established regarding the SCC's produced with fine and coarse recycled aggregates from the precast industry, based on its mechanical properties. The properties studied are strongly affected by the type and content of recycled aggregates. The potential demonstrated, mainly in the hardened state, by the joint use of fine and coarse recycled aggregate is emphasized.
本文旨在评估在预制行业重新引入再生混凝土骨料的可行性。对掺入来自破碎预制构件的再生骨料（RA）（粗再生骨料（CRA）和细再生骨料（FRA））的自密实混凝土（SCC）的力学性能进行了评估。目标是评估在掺入不同比例（FRA/CRA%：0/0%、25/25%、50/50%、0/100%和100/0%）的由具有相似目标性能的预制源混凝土生产的RA的情况下，生产出具有最低预先设定的力学强度性能的SCC的能力。针对两种强度等级（45MPa和65MPa）在SCC中进行了这种复制，目的是最终获得在工作性和力学强度方面其特性与含有天然骨料的SCC的特性相兼容的再生骨料混凝土。基于其力学性能，这些结果使得能够就由预制行业的细再生骨料和粗再生骨料生产的SCC得出结论。所研究的性能受到再生骨料的类型和含量的强烈影响。强调了细再生骨料和粗再生骨料联合使用主要在硬化状态下所展现出的潜力。
