Department of Civil Engineering, Hanyang University, Ansan 425-791, Republic of Korea.
Waste Manag. 2011 Nov;31(11):2352-60. doi: 10.1016/j.wasman.2011.06.014. Epub 2011 Jul 23.
Construction and demolition waste has been dramatically increased in the last decade, and social and environmental concerns on the recycling have consequently been increased. Recent technology has greatly improved the recycling process for waste concrete. This study investigates the fundamental characteristics of concrete using recycled concrete aggregate (RCA) for its application to structural concrete members. The specimens used 100% coarse RCA, various replacement levels of natural aggregate with fine RCA, and several levels of fly ash addition. Compressive strength of mortar and concrete which used RCA gradually decreased as the amount of the recycled materials increased. Regardless of curing conditions and fly ash addition, the 28 days strength of the recycled aggregate concrete was greater than the design strength, 40 MPa, with a complete replacement of coarse aggregate and a replacement level of natural fine aggregate by fine RCA up to 60%. The recycled aggregate concrete achieved sufficient resistance to the chloride ion penetration. The measured carbonation depth did not indicate a clear relationship to the fine RCA replacement ratio but the recycled aggregate concrete could also attain adequate carbonation resistance. Based on the results from the experimental investigations, it is believed that the recycled aggregate concrete can be successfully applied to structural concrete members.
在过去的十年中，建筑和拆除垃圾的产生量急剧增加，因此人们对其回收利用的社会和环境问题的关注也相应增加。最近的技术极大地改进了废混凝土的回收过程。本研究使用再生混凝土骨料（RCA）来研究混凝土的基本特性，以将其应用于结构混凝土构件。所使用的试件全部采用粗 RCA，用细 RCA 部分替代天然骨料，以及添加不同数量的粉煤灰。随着再生材料用量的增加，使用 RCA 的砂浆和混凝土的抗压强度逐渐降低。无论养护条件和粉煤灰的添加如何，完全用粗骨料替代和用细 RCA 替代高达 60%的天然细骨料的再生骨料混凝土的 28 天强度都大于设计强度 40MPa。再生骨料混凝土具有足够的抗氯离子渗透能力。测量的碳化深度与细 RCA 替代率没有明显的关系，但再生骨料混凝土也可以达到足够的抗碳化能力。根据实验研究的结果，可以认为再生骨料混凝土可以成功地应用于结构混凝土构件。
