碱激发钢铁固废混凝土强度形成机理  

Strength Formation Mechanism of Alkali-Activation Steel Solid Waste Concrete

作　　者：刘德坤 孙琦 LIU Dekun;SUN Qi(School of Civil Engineering,Liaoning Technical University,Fuxin 123000,China;Graduate School,Liaoning Technical University,Fuxin 123000,China)

机构地区：[1]辽宁工程技术大学土木工程学院,阜新123000 [2]辽宁工程技术大学研究生院,阜新123000

出　　处：《硅酸盐通报》2025年第3期1057-1068,共12页Bulletin of the Chinese Ceramic Society

基　　金：黑龙江省揭榜挂帅项目(2023ZXJ05A02)。

摘　　要：为综合利用钢铁固废,本文采用钢渣、矿渣、铁尾砂和天然碎石为原料,NaOH和Na_(2)SiO_(3)为激发剂进行混凝土制备。探究了钢渣和矿渣质量比、铁尾砂替代率、碱用量和碱模数对混凝土工作性能和力学性能的影响。通过微观测试和pH值试验揭示了碱激发钢铁固废混凝土的水化机理。结果表明,铁尾砂的加入改善了集料颗粒级配,提高了混凝土整体密实度。激发剂促进了钢渣和矿渣活性矿物的溶解,加快了混凝土水化反应进程。钢渣的掺入为C-S-H凝胶、C-A-S-H凝胶和Ca(OH)_(2)晶体的形成提供了丰富的Ca^(2+)。当钢渣和矿渣质量比为1∶9、铁尾砂替代率为45%(质量分数)、碱用量为6%(质量分数)、碱模数(SiO_(2)和Na_(2)O的摩尔比)为1.4时,碱激发钢铁固废混凝土28 d抗压强度达到47.6 MPa。In order to comprehensively utilize steel solid waste,this paper used steel slag,blast furnace slag,iron tailings and natural crushed sand as raw materials,NaOH and Na_(2)SiO_(3)as activators to prepare concrete.The effects of mass ratio of steel slag-to-blast furnace slag,iron tailings replacement rate,alkali dosage and alkali modulus on the working and mechanical properties of concrete were investigated.Based on microstructural analysis and pH test,the corresponding hydration mechanisms of alkali-activated steel solid waste concrete were revealed.The results show that the addition of iron tailings can improve the gradation of aggregates particles and enhance the overall compactness of concrete.The activators promote the dissolution of active minerals of steel slag and blast furnace slag,and speed up the hydration reaction process of concrete.The inclusion of steel slag can provide abundant Ca^(2+)for the formation of C-S-H gel,C-A-S-H gel and Ca(OH)_(2)crystal.When the mass of steel slag-to-blast furnace slag is 1∶9,the iron tailing replacement rate is 45%(mass fraction),the alkali dosage is 6%(mass fraction)and the alkali modulus(molar ratio of SiO_(2)and Na_(2)O)is 1.4,the 28 d compressive strength of alkali-activation steel solid waste concrete reaches 47.6 MPa.

关 键 词：碱激发 钢铁固废 混凝土材料 抗压强度 微观结构 水化机理 

分 类 号：TU528[建筑科学—建筑技术科学]