再生混凝土耐久性的试验研究 Ⅰ.再生混凝土的冻融循环试验

Durability Test Investigation on the Recycled Aggregate Concrete (Part 1 Freeze Dissolution Circulation Test on Recycled Aggregate Concrete )

在实验室预制C20普通混凝土,28d后用破碎机将其破碎筛选调配制成再生粗骨料与细骨料,以此再生骨料100%替代天然碎石和砂子制备再生混凝土,探讨了再生混凝土的耐久性能———抵抗冻融循环的能力。耐久性试验用混凝土水灰比质量分数分别为45%,65%。结果表明,100%再生混凝土(简称RR混凝土)试件的冻融循环抵抗性与粗、细骨料置换率为0%的普通混凝土(简称NN混凝土)试件相比,相对动弹性系数和耐久性系数分别降低6%和9%,但都能满足评价冻融循环抵抗性的最低指标。

C20 normal concrete was prepared, after 28 days crush processing was carried out in the laboratory and recycled coarse aggregate and recyled fine aggregate were obtained concrete was placed instead of a normal macadam and sand, using the recycled aggregate 100% , an analysis of the durable performace-repetition fregingthawing-resistance performance of recyeled concrete. The water cement ratio of the concrete for durability test are 0.45 and 0.65. However, the index used as the standard of freezing-thawing-resistance nature was satisfied.