本文进行同配合比条件下再生骨料混凝土(RAC)与基准混凝土力学性能比较的试验研究。采用来源于高、中、低三种不同水胶比(0.60、0.40、0.26)混凝土加工而成的再生骨料。配制RAC,测定抗压强度、劈裂抗拉强度和断裂能。同配合比RAC的断裂能比基准混凝土有所降低,且降幅随水胶比下降而增大。故低水胶比RAC的抗裂纹扩展能力较低。高水胶比RAC抗压强度略低于基准混凝土;而低水胶比RAC抗压强度则高于基准混凝土。是缘于再生骨料吸水性较高。使实际水胶比降低。但同等配合比条件下RAC的劈裂抗拉强度均低于基准混凝土。
An experimental research on comparison of mechanical properties between recycled aggregate concrete (RAC) and control concrete at identical mix proportions is presented. Concretes at three water/binder ratios (0.60, 0.40, and 0.26 ) were processed to form recycled aggregate (RA), which were further used to prepare RAC. Compressive strength, tensile splitring strength, and fracture energy were determined respectively. The results indicate that fracture energy of RAC was lower than that of control concrete at the same mix proportions. The lower the water/binder ratio, the greater the difference in fracture energy between RAC and control concrete. Therefore, RAC at a low water/binder ratio had a relatively low crack growth resistance, although its strength was relatively high. At a high water/binder ratio, compressive strength of RAC was slightly lower than that of control concrete, while at a low water/binder ratio, compressive strength of RAC was higher than that of control concrete, which is attributed to water absorption of RA, and decreased water/binder ratio. Nevertheless, tensile splitting strength of RAC was always lower than that of control concrete at the identical mix proportions.