为促进工业废弃物资源化利用并提升道路混凝土性能,系统评估了稻壳灰(RHA)对低细度自密实混凝土(LF-SCC)路用性能的影响.以0%~50%水泥替代率为变量,开展了工作性能、力学性能和耐久性测试,并结合扫描电子显微镜(SEM)、能谱分析(EDS)与压汞法(MIP)探讨其作用机理.结果表明:20%的RHA替代率表现最佳,其28 d抗压、劈裂抗拉及抗折强度分别提升5.73%、2.48%和2.50%,抗氯离子渗透性达“极低”水平,吸水率和渗透深度分别降低75%和60%.SEM和EDS分析表明,适量RHA通过促进火山灰反应生成大量C—S—H凝胶,显著优化孔隙结构;MIP测试显示28 d后20%RHA替代率的总孔隙率仅为5.34%,最可几孔径细化至28.9 nm,有害孔占比显著减少;而过量掺入则因未反应SiO2积聚导致性能劣化,推荐20%为最佳RHA掺量.
To promote the resource utilization of industrial waste and enhance the performance of road concrete, the effects of rice husk ash (RHA) on the performance of low-fineness self-compacting concrete (LF-SCC) for road applications were systematically evaluated. With cement replacement rates ranging from 0% to 50%, the workability, mechanical properties, and durability tests were conducted, and the mechanisms were explored through scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and mercury intrusion porosimetry (MIP). The results showed that the 20% RHA replacement rate yield the best performance. At 28 days, compressive strength, splitting tensile strength, and flexural strength are increased by 5.73%, 2.48%, and 2.50%, respectively. The chloride ion permeability reach an “extremely low” level, while water absorption and penetration depth are reduced by 75% and 60%, respectively. SEM and EDS analyses indicated that an appropriate amount of RHA promote pozzolanic reactions, resulting in the formation of large amounts of C—S—H gel, which significantly optimize the pore structure. MIP tests revealed that the total porosity with 20% RHA replacement rate at 28 days is only 5.34%, with the most probable pore diameter is reduced to 28.9 nm, and the proportion of harmful pores significantly is decreased. However, excessive incorporation of RHA lead to performance degradation due to the accumulation of unreacted SiO2. Therefore, the 20% RHA replacement rate is recommended as the optimal dosage.
[1] Bahmani H,Mostofinejad D.Sustainable self-compacting concrete:performance optimization using calcium oxide-activated slag and sugar factory lime waste[J].Construction and Building Materials,2025,492:142956.
[2] 韩建平,韩维丽,文旭皓,等.钢纤维对自密实混凝土工作性能和抗压韧性影响的试验研究[J].兰州理工大学学报,2024,50(5):112-117.
[3] 李京军,张雪莲,李哲,等. 冻融环境下钢纤维增强自密实轻骨料混凝土弯曲韧性研究[J].工程科学与技术,2025,57(2):214-222.
[4] 李静,呼浩楠.纤维增强自密实混凝土力学性能与孔结构特征[J].复合材料学报,2025,42(7):6104-6125.
[5] 汪镇,王磊,赵刚.纤维增强混凝土在复合盐半浸泡环境下的劣化性能[J].兰州理工大学学报,2025,51(5):21-28.
[6] Ali M B,Rahman S,Hossain M S.A review on emission analysis in cement industries[J].Renewable and Sustainable Energy Reviews,2011,15(5):2252-2261.
[7] 赵云,毕继红,王照耀,等.矿渣粉对钢纤维自密实混凝土性能的影响[J].建筑材料学报,2022,25(1):24-30.
[8] 滕晓丹,黎永鸿,韦宵宁,等.橡胶颗粒和稻壳灰复掺改性ECC拉压性能与裂缝特征[J].复合材料学报,2024,41(7):3716-3725.
[9] 余阳,邹桢,张春巍.稻壳灰混凝土耐久性研究综述[J].沈阳工业大学学报,2025,47(3):377-388.
[10] 侯永强,尹升华,王雷鸣,等.粉煤灰-稻壳灰基胶结充填体的力学性能、微观结构及参数优化[J].中国矿业,2025,34(8):178-189.
[11] Bauchkar S D,Chore H S.Experimental studies on rheological properties of smart dynamic concrete[J].Advances in concrete construction,2017,5(3):183-199.
[12] Kannur B,Chore H S.Assessing semiflowable self-consolidating concrete with sugarcane bagasse ash for application in rigid pavement[J].Journal of Materials in Civil Engineering,2023,35(10):4023358.
[13] Kannur B,Chore H S.Strength and durability study of low-fines self-consolidating concrete as a pavement material using fly ash and bagasse ash[J].European Journal of Environmental and Civil Engineering,2023,27(11):3507-3524.
[14] 何林,侯付闯.稻壳灰对水工混凝土性能的影响[J].水利技术监督,2024(9):205-208.
[15] 何越骁,黄维蓉,唐喜,等.C60细石自密实混凝土耐久性能影响因素试验研究[J].湖南大学学报(自然科学版),2023,50(12):92-101.
[16] JGJ 52—2006 普通混凝土用砂、石质量及检验方法标准[S].
[17] JGJ/T 283—2012 自密实混凝土应用技术规程[S].
[18] EFNARC-2005 The European guidelines for self-compacting concrete[S].
[19] GB/T 50081—2019 混凝土物理力学性能试验方法标准[S].
[20] GB/T 50082—2024 混凝土长期性能和耐久性能试验方法标准[S].
[21] JTG D40—2011 公路水泥混凝土路面设计规范[S].
[22] Alsheyab M A,Khasawneh M A,Abualia A,et al.A critical review of fatigue cracking in asphalt concrete pavement:a challenge to pavement durability[J].Innovative Infrastructure Solutions,2024,9(10):386.
[23] 李凯,杨璐璐,史才军.基于不规则骨料堆积结构的混凝土水渗透性的研究[J].材料导报,2024,38(12):103-110.
[24] 黄华,郭梦雪,张伟,等.粉煤灰-矿渣基地聚物混凝土力学性能与微观结构[J].哈尔滨工业大学学报,2022,54(3):74-84.
[25] 吴中伟.混凝土科学技术近期发展方向的探讨[J].硅酸盐学报,1979(3):262-270.
