Lu Dong, Zhong Jing, Yan Baobao, Gong Jing, He Ziye, Zhang Guanhua, Song Chengzhe
College of Urban Construction, Wuchang University of Technology, Wuhan 430223, China.
School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China.
Materials (Basel). 2021 Jan 4;14(1):215. doi: 10.3390/ma14010215.
It has been reported that iron tailing powder (ITP) has the potential to partially replace cement to prepare ultra-high-performance concrete (UHPC). However, the reactivity of ITP particles in concrete largely depends on the curing method. This study investigates the effects of curing conditions on the mechanical and microstructural properties of UHPC containing ITP. To achieve this objective, three research tasks are conducted, including (1) preparing seven concrete formulations by introducing ITP; (2) characterizing their mechanical performance under different curing regimes; and (3) analyzing their microstructure by XRD patterns, FTIR analysis, and SEM observation. The experimental results show that there is an optimum ITP dosage (15%) for their application. The concrete with 15% ITP under standard curing obtains 94.3 MPa at 7 days, their early-age strength could be even further increased by ~30% (warm-water curing) and ~35% (steamed curing). The steam curing regime stimulates the activity of ITP and refines the microstructure. This study demonstrates the potential of replacing Portland cement with ITP in UHPC production.
据报道，铁尾矿粉（ITP）有潜力部分替代水泥来制备超高性能混凝土（UHPC）。然而，ITP颗粒在混凝土中的反应活性很大程度上取决于养护方法。本研究调查了养护条件对含ITP的UHPC力学性能和微观结构性能的影响。为实现这一目标，开展了三项研究任务，包括（1）通过引入ITP制备七种混凝土配方；（2）表征它们在不同养护制度下的力学性能；（3）通过XRD图谱、FTIR分析和SEM观察来分析它们的微观结构。实验结果表明，其应用存在一个最佳ITP用量（15%）。在标准养护下含15% ITP的混凝土在7天时抗压强度达到94.3 MPa，其早期强度通过温水养护可进一步提高约30%，通过蒸汽养护可进一步提高约35%。蒸汽养护制度激发了ITP的活性并细化了微观结构。本研究证明了在UHPC生产中用ITP替代波特兰水泥的潜力。
