摘要
机制砂石粉部分替代粉煤灰是铁路工程中制备混凝土的重要技术手段。针对云南弥蒙铁路建设沿线缺乏优质粉煤灰的工程现状,通过制备20%低品质粉煤灰+80%水泥、10%石粉+10%低品质粉煤灰+80%水泥以及20%石粉+80%水泥3类胶凝材料体系,研究石粉替代粉煤灰对铁路混凝土性能的影响。结果表明:石粉和粉煤灰复掺可改善浆体的工作性;石粉替代粉煤灰均会降低混凝土的抗压强度和弹性模量,对C40混凝土的影响更大;石粉替代率的增加会增大硬化浆体的56 d电通量,加剧浆体的干燥收缩,扩大碳化深度,但对抗冻融性能影响较小。
It is the crucial technology in railway engineering to substitute stone powder from the production of manufactured sand for fly ash on concrete.On the background that high-quality fly ash is scarce along the Mi-Meng railway in Yunnan province,this article prepared three cementitious materials systems:20%lower-grade fly ash+80%cement,10%stone powder+10%lower-grade fly ash+80%cement as well as 20%stone powder+80%cement.The effect using stone powder instead of fly ash on the properties of railway concrete was studied.The results suggested that the compressive strength and elastic modular of concrete,particularly C40 concrete,were reduced by the replacement.When increasing the incorporation of stone powder,the 56-day electric flux of concrete increased,the drying shrinkage of hardened paste was more intense and the carbonation depth was increased,but the freeze-thaw resistance of concrete could basically remain unchanged.
作者
宋小兵
任达元
张轩伟
夏京亮
王晶
关青锋
周永祥
SONG Xiaobing;REN Dayuan;ZHANG Xuanwei;XIA Jingliang;WANG Jing;GUAN Qingfeng;ZHOU Yongxiang(The 4th Engineering Co.Ltd.,of China Railway 12th Bureau Group,Xi'an 710021,China;China Academy of Building Research,Beijing 100013,China;State Key Laboratory of Building Safety and Environment,Beijing 100013,China)
出处
《新型建筑材料》
2021年第4期27-31,共5页
New Building Materials
关键词
机制砂石粉
粉煤灰
混凝土
力学性能
耐久性能
stone powder in manufactured sand
fly ash
concrete
mechanical property
durability
