煤矸石集料混凝土抗压强度及耐久性能  

Compressive Strength and Durability of Coal Gangue Aggregate Concrete

作　　者：马宏强[1] 易成[1] 朱红光[1] 董作超[2] 陈宏宇 王佳欣 李德毅 MA Hongqiang;YI Cheng;ZHU Hongguang;DONG Zuochao;CHEN Hongyu;WANG Jiaxin;LI Deyi(School of Mechanics and Civil Engineering,China University of Mining and Technology（Beijing）,Beijing 100083;School of Architecture and Civil Engineering,Jiangsu University of Science and Technology,Zhenjiang 212005)

机构地区：[1]中国矿业大学(北京)力学与建筑工程学院,北京100083 [2]江苏科技大学土木工程与建筑学院,镇江212005

出　　处：《材料导报》2018年第14期2390-2395,共6页Materials Reports

基　　金：国家自然科学基金(51578539);北京市自然科学基金(8164061)

摘　　要：以煤矸石-普通碎石混合作为粗集料制备了一系列混凝土试样,其中煅烧和未煅烧煤矸石等量替代普通碎石的掺量为0%、30%、50%、70%和100%,探究了煤矸石粗集料掺量和700℃煅烧对混凝土抗压强度、快速氯离子渗透、抗碳化性能和抗硫酸盐侵蚀性能的影响,并借助X射线衍射仪(XRD)观测矿物成分变化,利用扫描电子显微镜(SEM)观测微观结构。实验结果表明煤矸石作混凝土集料是可行的,最大掺量受混凝土设计强度和所处环境的限制。煤矸石与胶凝材料粘结处空腔的存在不利于混凝土抗压强度和耐久性能,但对固化氯离子性能有利。相比于掺未煅烧煤矸石的混凝土,掺煅烧煤矸石的混凝土的内部结构更致密,但煅烧煤矸石自身的缺陷导致其未获得较大优势。后续研究将致力于更大程度地激发煅烧煤矸石集料的活性以更好地发挥其优势。本研究为煤矸石的大宗高效利用提供试验基础和理论依据。We herein prepared a series of concrete specimens with the mixed coarse aggregate of coal gangue and ordinary gravel,in which the calcined or uncalcined coarse coal gangue equivalently substituted for 0%,30%,50%,70% and 100% of the gravel.The influences of substitution amount and 700 ℃ calcination of coarse coal gangue on compressive strength,anti-carbonation performance,rapid chloride ion penetration and sulfate attack resistance of the concrete were investigated,and the mineral composition changes and the microstructure were observed by XRD and SEM,respectively.Our experiment validated the feasibility of utilizing coal gangue as coarse aggregate for concrete,with a maximum substitution amount determined by the concrete＇s designed strength and environmental factors.The existence of the cavities at the bond between the coal gangue and the cementing material inhibits compressive strength and durability of the concrete,but is beneficial to the concrete＇s resistance against chloride ion permeation.The substitution of calcined coarse coal gangue can result in a more dense concrete structure compared to uncalcined coarse coal gangue,and nonetheless holds slight advantage due to its intrinsic defects.Further research is expected to promote the excitation upon the calcined coarse coal gangue aggregate and amplify its advantage.The present work can provide experimental basis and theoretical reference for the highly efficient utilization of coal gangue.

关 键 词：煤矸石 抗压强度 快速氯离子渗透 抗碳化性能 抗硫酸盐侵蚀 粗集料混凝土 

分 类 号：TU528.59[建筑科学—建筑技术科学]