摘要
为实现肯尼亚资源的高效利用,采用Athi River地区丰富的凝灰岩作为矿物掺合料制备高强混凝土,研究凝灰岩掺量和养护制度对混凝土拌合物性能、力学性能、抗氯离子渗透和抗碳化性能的影响。结果显示,随凝灰岩掺量增加,混凝土拌合物的增实因数和含气量均先增大后减小;掺入凝灰岩会导致混凝土抗压强度降低,但不同的养护方式表现出不同的强化作用,蒸养通过火山灰效应提高混凝土早期强度,标养通过优化内部孔结构提高混凝土后期强度;凝灰岩掺量为10%时,混凝土氯离子扩散系数最小,当凝灰岩掺量为5%~10%时,建议采用标养;当凝灰岩掺量为15%~25%时,建议采用蒸养;混凝土抗碳化性能受养护条件影响较大,蒸养可以有效抵抗碳化侵蚀。
To achieve efficient utilization of resources in the Kenyan region,volcanic ash from the Athi River area,rich in tuff,is used as a mineral admixture to prepare high-strength concrete.This study investigates the effects of the amount of tuff admixture and curing regimes on the properties of concrete mixtures,mechanical properties,chloride ion penetration resistance,and carbonation resistance.The results show that as the amount of tuff admixture increases,both the bulking factor and air content of the concrete mixture first increase and then decrease.The incorporation of tuff leads to a reduction in the compressive strength of the concrete,but different curing methods exhibit varying degrees of strengthening effect.Steam curing enhances the early strength of the concrete through the pozzolanic effect,while standard curing optimizes the internal pore structure to improve the later strength of the concrete.When the tuff admixture is 10%,the chloride ion diffusion coefficient of the concrete is at its minimum.It is recommended to use standard curing when the tuff admixture is between 5%and 10%,and steam curing when the tuff admixture is between 15%and 25%.The carbonation resistance of the concrete is significantly affected by the curing conditions,steam curing can effectively resist carbonation erosion.
作者
王恒
董藏龙
路珏
夏京亮
WANG Heng;DONG Zanglong;LU Jue;XIA Jingliang(China Road and Bridge Engineering Co.Ltd.,Beijing 100011,China;CCCC Fourth Navigation Engineering Bureau Co.Ltd.,Guangzhou 510290,China;China Academy of Building Research,Beijing 100013,China)
出处
《新型建筑材料》
2024年第9期104-107,124,共5页
New Building Materials
关键词
高强混凝土
凝灰岩
拌合物性能
力学性能
耐久性能
high strength concrete
tuff
mixing properties
mechanical property
durability properties
