摘要
为扩大煤炭工业固体废弃物煤矸石在建筑行业的利用场景,降低天然建筑材料使用量,减小环境污染,采用煤矸石制备粗骨料取代天然碎石,以粉煤灰、硅灰作为补强矿物材料制备煤矸石混凝土,研究干湿循环对煤矸石混凝土抗氯盐侵蚀机理及影响。结果表明:随氯盐干湿循环侵蚀作用次数增加,煤矸石混凝土的抗压强度呈先增大后降低、质量损失率呈先减小后增大趋势,煤矸石取代率为25%、50%的混凝土相对动弹性模量先增大后减小,相同深度处自由氯离子含量不断增大;随煤矸石取代率增加,150次干湿循环后抗压强度、相对动弹性模量减小,质量损失率、自由氯离子含量增大;经粉煤灰、硅灰补强作用,煤矸石取代率为25%、50%的混凝土抗氯盐侵蚀性能大于天然碎石混凝土,取代率超过50%后,抗氯盐侵蚀性能迅速降低。研究成果可为氯盐侵蚀环境下煤矸石混凝土的应用提供理论支撑。
To expand the utilization scenarios of coal gangue,a solid waste from the coal industry,in the construction sector,reduce the consumption of natural building materials,and minimize environmental pollution,coal gangue was used to prepare coarse aggregates as a substitute for natural crushed stone.Fly ash and silica fume were employed as reinforcing mineral materials to produce coal gangue concrete.This study investigated the mechanism and impact of wet-dry cycles on the resistance of coal gangue concrete to chloride salt erosion.The results showed that as the number of wet-dry cycles of chloride salt erosion increased,the compressive strength of coal gangue concrete first increased and then decreased,while the mass loss rate first decreased and then increased.The relative dynamic elastic modulus of concrete with 25%and 50%coal gangue replacement rates first increased and then decreased,and the free chloride ion content at the same depth continuously increased.With an increase in the coal gangue replacement rate,after 150 wet-dry cycles,the compressive strength and relative dynamic elastic modulus decreased,while the mass loss rate and free chloride ion content increased.Due to the reinforcing effects of fly ash and silica fume,the chloride erosion resistance of concrete with 25%and 50%coal gangue replacement rates exceeded that of natural crushed stone concrete.However,when the replacement rate exceeded 50%,the chloride erosion resistance decreased rapidly.The research findings provide theoretical support for the application of coal gangue concrete in chloride erosion environments.
作者
史艳忠
SHI Yanzhong(Shenmu Vocational&Technical College,Shenmu 719300,China;Xi’an University of Architecture and Technology,Xi’an,710055,China)
出处
《粉煤灰综合利用》
2025年第4期29-34,共6页
Fly Ash Comprehensive Utilization
基金
陕西省教育厅2022年度一般专项科研计划项目(自然科学项目)(22JK0369)
神木职业技术学院科学研究计划项目(2024ZK09)。
关键词
煤矸石粗骨料
混凝土
干湿循环
氯盐侵蚀
劣化规律
gangue coarse aggregate
concrete
wet and dry cycles
chlorine salt erosion
deterioration pattern
作者简介
史艳忠(1983-),男,博士研究生,副教授,研究方向:建筑工程、岩土工程。
