纳米二氧化硅与钢纤维对再生混凝土力学性能的影响  

Effect of nano-silica and steel fibers on the mechanical properties of recycled aggregate concrete

作　　者：王俊波[1,2] 申贺文 王永贵 黄旭阳[1] WANG Junbo;SHEN Hewen;WANG Yonggui;HUANG Xuyang(College of Civil Engineering,Henan Polytechnic University,Jiaozuo 454000,China;China Construction Seventh Engineering Division.Co.,Ltd.,Zhengzhou 450004,China;Henan Province Engineering Laboratory for Eco-architecture and Built Environment,Henan Polytechnic University,Jiaozuo 454000,China)

机构地区：[1]河南理工大学土木工程学院,河南焦作454000 [2]中国建筑第七工程局有限公司,河南郑州450004 [3]河南理工大学生态建筑与环境构建河南省工程实验室,河南焦作454000

出　　处：《武汉科技大学学报》2025年第2期121-132,共12页Journal of Wuhan University of Science and Technology

基　　金：国家自然科学基金项目(51608179);河南省科技攻关项目(242102320361);河南理工大学基本科研业务费专项项目(NSFRF240627).

摘　　要：为提高再生混凝土的力学性能,通过掺入纳米SiO_(2)与钢纤维对其进行改性。以再生骨料取代率、纳米SiO_(2)及钢纤维掺量为控制参数,利用力学性能试验,分析了不同参数对再生混凝土破坏形态、力学性能、弯曲韧性的影响。结果表明,掺入钢纤维有利于改善再生混凝土力学性能,尤其能明显提高混凝土的劈裂抗拉强度及抗折强度。掺入纳米SiO_(2)可使再生混凝土力学性能均有所提高,同时可改善钢纤维再生混凝土延性。与单一掺入钢纤维或纳米SiO_(2)相比,复合掺入纳米SiO_(2)与钢纤维对再生混凝土各项力学性能的提升效果更显著,最佳的纳米SiO_(2)与钢纤维掺量分别为1%、1.5%。掺入纳米SiO_(2)可提高钢纤维再生混凝土的弯曲韧性,复合掺入纳米SiO_(2)与钢纤维对混凝土弯曲韧性的提升效果要优于单独掺入纳米SiO_(2)或钢纤维。建议采用JG/T 472—2015《钢纤维混凝土》标准评价纳米SiO_(2)与钢纤维增强再生混凝土的弯曲韧性。To enhance the mechanical properties of recycled aggregate concrete,modifications were implemented by incorporating nano-silica(SiO_(2))and steel fibers.The study employed mechanical performance tests to analyze the effects of key control parameters—recycled aggregate replacement ratio,nano-SiO_(2)dosage,and steel fiber content—on the failure mode,mechanical properties,and flexural toughness of recycled aggregate concrete.The results show that the addition of steel fibers significantly improved the mechanical properties of recycled aggregate concrete,particularly enhancing its splitting tensile strength and flexural strength.Nano-SiO_(2)improved the overall mechanical performance of recycled aggregate concrete and enhanced the ductility of steel fiber-reinforced recycled aggregate concrete.Compared with individual incorporation of steel fibers or nano-SiO_(2),the synergistic use of nano-SiO_(2)and steel fibers yielded more pronounced improvements in all mechanical properties of recycled aggregate concrete.The optimal dosages were identified as 1%nano-SiO_(2)and 1.5%steel fibers.Nano-SiO_(2)enhanced the flexural toughness of steel fiber-reinforced recycled aggregate concrete,and the combined application of nano-SiO_(2)and steel fibers outperformed either material used independently in improving flexural toughness.It is recommended that the JG/T 472—2015 standard be adopted to evaluate the flexural toughness of nano-SiO_(2)and steel fiber-enhanced recycled aggregate concrete.

关 键 词：再生混凝土 再生骨料 纳米SiO_(2) 钢纤维 破坏形态 力学性能 弯曲韧性 

分 类 号：TU528[建筑科学—建筑技术科学]