水泥和粉煤灰稳定钢渣-砼再生碎石路基混合料的制备及其性能  

Preparation and properties of subgrade mixture made of steel slag-concrete regeneration gravel stabilized with cement and fly ash

作　　者：程银银 李宏波[2,3] 康鑫睿 丁永发 童彧斐 CHENG Yinyin;LI Hongbo;KANG Xinrui;DING Yongfa;TONGYufeia(School of Civil and Hydraulic Engineering,Ningxia University,Yinchuan 750021,China;Ningxia Engineering and Technology Research Center for Water-saving Irrigation and Water Resources Regulation,Ningxia University,Yinchuan 750021,China;Ningxia Engineering Technology Research Center for Civil Engineering Seismic and Disaster Mitigation,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学土木与水利工程学院,宁夏银川750021 [2]宁夏大学宁夏节水灌溉与水资源调控工程技术研究中心,宁夏银川750021 [3]宁夏大学宁夏土木工程防震减灾工程技术研究中心,宁夏银川750021

出　　处：《中国粉体技术》2023年第4期11-21,共11页China Powder Science and Technology

基　　金：宁夏重点研发计划项目,编号:2021BDE92002;宁夏高等学校一流学科(水利工程学科)资助项目,编号:NXYLXK2021A03。

摘　　要：为减少对天然碎石的开采量,解决工业废渣和建筑固体废弃物大量堆积的问题,采用水泥和粉煤灰稳定钢渣-砼再生碎石制备路基混合料。在水泥和粉煤灰的掺量范围确定的情况下,通过干湿循环试验确定钢渣和砼再生碎石的较优质量比;当钢渣和砼再生碎石选取较优质量比时,通过三轴试验测试混合料的力学性能,进一步优化水泥和粉煤灰的质量分数;利用X射线衍射、扫描电子显微镜、能量色散X射线谱分析不同龄期制得的混合料的组成、微观结构及水化反应特征产物的变化规律,研究混合料的形成机制和强度影响因素。结果表明:当钢渣和砼再生碎石的质量比为3:1时,制得的混合料的相对强度最高,失质量分数最小;当水泥掺入质量分数为5%、粉煤灰掺入质量分数为16%、钢渣和砼再生碎石的质量比为3:1时,制得的混合料黏聚力最强,抗剪强度最大,力学性能较优;在水化早期掺入钢渣可增加钙矾石的生成量,提高制得的混合料的强度;制得的混合料的水化产物以水化硅酸钙、氢氧化钙和钙矾石为主;钙离子浓度的增加能增强制得的混合料的水化产物碱性,缩短硅酸钙水化物中的硅氧四面体链,降低制得的混合料的聚合度。In order to reduce the amount of natural gravel mining and solve the problem of large amount of industrial waste and construction solid waste accumulation,cement and fly ash were used to stabilize steel slag and concrete regeneration gravel,and subgrade mixture was prepared.The better quality ratio of steel slag and concrete regeneration gravel was determined by dry and wet cycle test when the content range of cement and fly ash was determined.On the basis of selecting the better quality ratio of steel slag and concrete regeneration gravel,the mechanical properties of the mixture were tested by triaxial test to further optimize the content of cement and fly ash.X-ray diffraction,scanning electron microscope and energy dispersive X-ray spectrum were used to analyze the composition,microstructure and changes of the characteristic products ofhydration reaction of mixtures of different ages,and the formation mechanism and strength influencing factors of mixtures were studied.The results prove that the relative strength of the mixture is the highest and the mass loss fraction is the lowest when the mass ratio of steel slag and concrete regeneration gravel is 3:1.When the cement mass fraction is 5%,the fly ash mass fraction is 16%,and the mass ratio of steel slag and concrete regeneration gravel is 3:1,the mixture has the strongest cohesion,the largest shear strength and better mechan-ical properties.The addition of steel slag in the early stage of mixture hydration can increase the amount of ettringite generation and improve the strength of the mixture.The hydration products of the mixture are mainly calcium silicate hydrate,calcium hydroxide and ettringite.The increasing of calcium ion concentration increases the alkalinity of the system,shortens the silicon-oxygen tetrahedral chain in calcium silicate hydrateand reduces the polymerization degree of the mixture.

关 键 词：粉煤灰 钢渣-砼再生碎石 路基混合料 干湿循环试验 三轴试验 

分 类 号：TU521.2[建筑科学—建筑技术科学] TB4[一般工业技术]