School of Materials Science and Engineering, Southeast University, Nanjing, 210096, Jiangsu, China.
Jiangsu Transportation Research Institute, Nanjing, 211112, Jiangsu, China.
Environ Sci Pollut Res Int. 2022 Jan;29(3):3616-3628. doi: 10.1007/s11356-021-15883-2. Epub 2021 Aug 14.
Nowadays, utilizing large amount industrial by-product fly ash (FA) as the alternatives for cement in self-compacting concrete (SCC) had attracted more attention. In this study, FA was employed in SCC at five levels (0 %, 20 %, 30 %, 40 %, 50 %). The mechanical behaviors, the water porosities, the transport properties, and the sustainability of FA series SCC were investigated. At the initial curing stage (3 days), the use of FA in SCC reduces mechanical properties and increases water porosity, water absorption and water absorption coefficient (sorptivity) of SCC. FA series SCC have the lower resistance against carbon dioxide attack and chloride ion penetration than cement-based SCC. The prolonging curing time is beneficial to improve the long-term behaviors of FA- blended SCC. After SCC made by 20 %, 30 %, and 40 % FA water-curing for 90 days, there are the reduction of 0.44-2.09 % in the mechanical behaviors and the increase of 0.082-0.41 % in the water porosity, compared to pure-cement SCC. Beyond the content of FA (40 %), the difference s of the mechanical properties and the water porosity between SCC with 50 % FA and fully cement SCC are below the value of 2.5 %. With the progress in the curing time, the largest reduction rates of the water absorption and the sorptivity in all SCC mixtures were found in 50 % FA-blended SCC. Utilizing 50 % FA in SCC reduces the total charge passed values of SCC. The manufacture of 50 % FA-blended SCC has the lowest energy consumption and released amounts of CO, NO, and SO in all series SCC mixtures. The application of high-level FA to SCC is the positive assistance to prepare sustainable SCC with satisfying long-term behaviors.
如今,利用大量工业副产品粉煤灰(FA)替代水泥在自密实混凝土(SCC)中的应用引起了更多关注。本研究在 SCC 中使用 FA 五个水平(0%、20%、30%、40%、50%)。研究了 FA 系列 SCC 的力学性能、水分孔隙率、传输性能和可持续性。在初始养护阶段(3 天),FA 在 SCC 中的使用降低了力学性能,增加了 SCC 的水分孔隙率、吸水率和吸水率系数(吸水性)。FA 系列 SCC 的抗二氧化碳侵蚀和氯离子渗透能力低于水泥基 SCC。延长养护时间有利于改善 FA 掺 SCC 的长期性能。用 20%、30%和 40%FA 水养护 90 天后的 SCC,其力学性能降低 0.44-2.09%,水分孔隙率增加 0.082-0.41%,与纯水泥 SCC 相比。超过 FA 含量(40%)后,50%FA SCC 和全水泥 SCC 的力学性能和水分孔隙率差异均低于 2.5%。随着养护时间的延长,所有 SCC 混合物中吸水率和吸水性的最大降低率均出现在 50%FA 掺合 SCC 中。在 SCC 中使用 50%FA 可降低 SCC 的总电荷量。在所有系列 SCC 混合物中,50%FA 掺合 SCC 的制造能耗最低,CO、NO 和 SO 的释放量最低。在 SCC 中应用高水平 FA 是制备具有令人满意的长期性能的可持续 SCC 的积极辅助。