铁尾矿渣细度对水泥基材料流变和力学性能的影响  

Effect of Iron Tailing Fineness on Rheological and Mechanical Properties of Cement-based Materials

作　　者：陈登 卢继达 陈森森 CHEN Deng;LU Jida;CHEN Sensen(College of Civil Engineering,Suzhou University of Science and Technology,Suzhou 215011,China;Nanjing Kangtai Construction Grouting Technology Co.,Ltd.,Nanjing 210019,China)

机构地区：[1]苏州科技大学土木工程学院,江苏苏州215011 [2]南京康泰建筑灌浆科技有限公司,江苏南京210019

出　　处：《金属矿山》2025年第1期309-314,共6页Metal Mine

基　　金：国家自然科学基金项目(编号:52208279);江苏省自然科学基金项目(编号:BK20220639);江苏省高等学校自然科学研究面上项目(编号:20KJB560007)。

摘　　要：基于提高铁尾矿渣细度有利于激发其活性,为给铁尾矿渣的大宗利用提供理论依据,以平均粒径36、14、7μm的铁尾矿渣同比例替代水泥对复合水泥水化热、流变性和力学性能的影响进行了研究,并采用X射线衍射仪和差热-热重分析仪研究了铁尾矿渣对水泥水化产物和水化程度的影响,分析了其影响机理。结果表明:在相同铁尾矿渣掺量下,细度的提高能够有效提高复合水泥水化的放热速率和放热量,其中掺入10%、20%平均粒径为14μm或7μm的铁尾矿渣的复合水泥的水化放热量均高于纯水泥。掺入铁尾矿渣可以降低水泥浆体的黏度和剪切应力,提高水泥浆体的流动度,且铁尾矿渣越细,水泥浆体的流动度越高。磨细铁尾矿渣会促进其组成中的白云石、方解石与水泥浆体中的氢氧化钙反应,水化生成半碳铝酸钙和单碳铝酸钙,消耗氢氧化钙,增加复合水泥浆体试件的结合水量,从而有效促进复合水泥砂浆试件强度的发展。当铁尾渣平均粒径为7μm、掺量为10%时,复合水泥砂浆试件各龄期的抗折和抗压强度均高于纯水泥砂浆试件,有利于铁尾矿渣作为混凝土掺合料的高值化应用。Based on the fact that increasing the fineness of iron tailings slag is beneficial to stimulate its activity,in order to provide a theoretical basis for the mass utilization of iron tailings slag,the effects of iron tailings slag with average particle size of 36,14 and 7μm on the hydration heat,rheology and mechanical properties of composite cement were studied.The effects of iron tailings slag on the hydration products and hydration degree of cement were studied by X-ray diffractometer and differential thermal-thermogravimetric analyzer,and the influence mechanism was analyzed.The results showed that under the same content of iron tailings,the increase of fineness of iron tailings can effectively improve the heat release rate and heat release of hydration of composite cement.The hydration heat release of composite cement with 10%and 20%iron tailings with an average particle size of 14μm or 7μm is higher than that of pure cement.The addition of iron tailings slag can reduce the viscosity and shear stress of cement paste and improve the fluidity of cement paste.The finer the iron tailings slag,the higher the fluidity of cement paste.The fine iron tailings slag will promote the reaction of dolomite and calcite in its composition with calcium hydroxide in the cement paste,and hydrate to form semi-carbon calcium aluminate and single-carbon calcium aluminate,consume calcium hydroxide,and increase the amount of bound water in the composite cement paste specimen,thereby effectively promoting the development of the strength of the composite cement mortar specimen.When the average particle size of iron tailings is 7μm and the dosage is 10%,the flexural and compressive strength of composite cement mortar specimens at each age are higher than those of pure cement mortar specimens,which is beneficial to the high value application of iron tailings as concrete admixture.

关 键 词：铁尾矿渣 细度 水化热 流变性能 强度 

分 类 号：TU528[建筑科学—建筑技术科学]