粉煤灰影响再生细骨料混凝土抗压性能的试验研究

Experiment on Compressive Strength of Fly Ash in Recycled Fine Aggregate Concrete

通过室内试验,研究了粉煤灰等量取代水泥对再生细骨料混凝土抗压强度及其离散性的影响。试验结果表明:(1)粉煤灰等量取代水泥使得再生细骨料混凝土早期抗压强度降低,但后期抗压会超过或接近不掺粉煤灰的再生细骨料混凝土。(2)随着粉煤灰取代水泥率的增加,再生细骨料混凝土的后期抗压强度是先增大后减小,最佳取代率在15%～20%之间。3)随着粉煤灰取代水泥率的增加,再生细骨料混凝土抗压强度的离散性越大。

According to the cubic compressive strength experiment, authors studied the effects of compressive strength and discreteness due to different replacement ratio of fly ash in the recycled fine aggregate （RFA） concrete. The results illustrates that 1） an equal amount of fly ash replacing cement will reduce the early strength of RFA concrete, while the late strength will be more than or close to those without fly ash admixture.2）With the increase of fly ash replacing cement rate, late strength of RFA concrete is first increases then decreases,the best substitute rate is between 15% and 20%. 3） The growth of fly ash replacing ratio will lead the discreteness of RFA concrete＇s compressive strength become higher.