Influence of field recycled coarse aggregate on properties of concrete
Influence of field recycled coarse aggregate on properties of concrete
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DOI：
10.1617/s11527-010-9620-x
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发表时间：
2011-01-01
影响因子：
3.8
通讯作者：
Barai, S. V.
中科院分区：
文献类型：
--
作者：
Rao, M. Chakradhara;Bhattacharyya, S. K.;Barai, S. V.
本文研究了从已拆除的15年RCC涵洞中获得的不同量的再生粗骨料对再生骨料混凝土（RAC）性能的影响。引入了一个新术语，称为“粗骨料替代率（CRR）”，其定义为再生粗骨料的重量与混凝土混合物中粗骨料总重量的比率。为了分析混凝土在新拌和硬化状态下的性能，混凝土配合比中采用了 0、0.25、0.50 和 1.0 的粗骨料替代率。研究了抗压强度和间接拉伸强度、弹性模量、吸水率、空隙体积、硬化混凝土密度和氯化物渗透深度等性能。从实验结果可以看出，在所有粗骨料替代率下，湿养护 7 天后在空气中养护的混凝土比在水下完全养护 28 天的混凝土表现出更好的强度。由于再生骨料上粘附的旧砂浆具有较高的吸收能力，再生骨料混凝土的空隙体积和吸水率分别比普通混凝土高2.61%和1.82%。抗压强度、抗拉强度和弹性模量之间的关系是通过文献中报道的普通混凝土和再生骨料混凝土模型进行开发和验证的。此外，还报告了回弹数和 UPV（超声波脉冲速度）等无损检测参数。该研究证明了现场再生粗骨料（RCA）在混凝土中的潜在用途。
This paper investigates the influence of different amounts of recycled coarse aggregates obtained from a demolished RCC culvert 15 years old on the properties of recycled aggregate concrete (RAC). A new term called "coarse aggregate replacement ratio (CRR)" is introduced and is defined as the ratio of weight of recycled coarse aggregate to the total weight of coarse aggregate in a concrete mix. To analyze the behaviour of concrete in both the fresh and hardened state, a coarse aggregate replacement ratio of 0, 0.25, 0.50 and 1.0 are adopted in the concrete mixes. The properties namely compressive and indirect tensile strengths, modulus of elasticity, water absorption, volume of voids, density of hardened concrete and depth of chloride penetration are studied. From the experimental results it is observed that the concrete cured in air after 7 days of wet curing shows better strength than concrete cured completely under water for 28 days for all coarse aggregate replacement ratios. The volume of voids and water absorption of recycled aggregate concrete are 2.61 and 1.82% higher than those of normal concrete due to the high absorption capacity of old mortar adhered to recycled aggregates. The relationships among compressive strength, tensile strengths and modulus of elasticity are developed and verified with the models reported in the literature for both normal and recycled aggregate concrete. In addition, the non-destructive testing parameters such as rebound number and UPV (Ultrasonic pulse velocity) are reported. The study demonstrates the potential use of field recycled coarse aggregates (RCA) in concrete.