水镁石纤维-钢渣细骨料混凝土力学性能研究

Study on Mechanical Properties of Brucite Fiber-Steel Slag Fine Aggregate Concrete

为进一步提高钢渣利用率,降低环境污染,针对钢渣细骨料劣化混凝土力学性能现状,引入水镁石纤维,研究不同钢渣细骨料、水镁石纤维掺量对混凝土抗压及抗弯拉强度影响,探讨钢渣细骨料劣化混凝土性能机制,分析水镁石纤维对钢渣细骨料混凝土增强机理。结果表明,随着钢渣细骨料取代率逐步增加,混凝土坍落度下降,抗压强度及抗弯拉强度均不同程度降低。复掺水镁石纤维对钢渣细骨料混凝土的早期强度增强效果明显,与不掺水镁石纤维的30%钢渣混凝土相比,掺入30%钢渣细骨料与0.2%水镁石纤维,混凝土7 d抗压强度及抗弯拉强度分别提高15.75%、10.50%。水镁石纤维可以在水化产物间产生桥接作用,延缓裂纹发展。

To further promote the utilization of steel slag and reduce environmental pollution,brucite fiber is introduced.The influence of different steel slag fine aggregates and brucite fiber contents on concrete’s compressive and flexural strength is investigated.The performance mechanism of deteriorated concrete with steel slag fine aggregate and the reinforcement mechanism of brucite fiber in concrete with steel slag fine aggregate are discussed.The results show that as the steel slag replacement rate gradually increases,the workability of concrete decreases,and the compressive and flexural strength decreases to different degrees.The combined use of brucite fiber significantly enhances the early strength of concrete with steel slag fine aggregate,compared with 30%steel slag concrete without brucite fiber,the 7 d compressive strength and flexural tensile strength of the concrete with 30%steel slag fine aggregate and 0.2%brucite fiber increase by 15.75%and 10.50%,respectively.Brucite fiber can act as a bridge between hydration products,delay crack development.