基于一种尾矿制备高强混凝土用复合掺合料的试验研究  

Experimental study of composite admixture in high strength concrete based on tailings powder

作　　者：郭宇轩 马永胜 蒋泽宇 刘瑞朝 庄凯群 GUO Yuxuan;MA Yongsheng;JIANG Zeyu;LIU Ruichao;ZHUANG Kaiqun(Beijing Key Laboratory of Advanced Functional Materials for Building and Environment,Beijing University of Civil Engineering and Architecture,Beijing 100044,China;School of Civil Engineering,Harbin Institute of Technology,Harbin 150006,China)

机构地区：[1]北京建筑大学建筑结构与环境修复功能材料北京市重点试验室,北京100044 [2]哈尔滨工业大学土木工程学院,哈尔滨150006

出　　处：《建筑结构》2023年第24期85-90,共6页Building Structure

基　　金：高浓硫酸盐环境下高性能混凝土配制与应用技术研究(2021-ZJSGHKHI-18)。

摘　　要：以矿粉、粉煤灰、尾矿微粉为主要粉体材料,通过对矿粉、尾矿微粉进行研磨,且对尾矿微粉采用SEM电镜扫描方法进行微观形貌分析,研究不同比表面积的矿粉、尾矿微粉的胶砂性能及与混凝土外加剂的相容性。根据试验结果,结合各粉体材料独特效应,以尾矿微粉占比为50%固定值,与其他粉体材料按照一定比例进行复配,研发一种高强混凝土用复合掺合料,并以此为基础改善其性能,自主研发一种以高活性、高流变、降粘为特点的易流型高强混凝土用复合掺合料。研究表明:与目前市场销售的一种成品超细复合料相比,易流型高强混凝土用复合掺合料7d和28d活性指数分别提高7%和3%,流动度比提高4%,更能满足高强混凝土强度和工作性的需求;易流型高强混凝土用复合掺合料和成品超细复合掺合料在C70、C80、C90高强混凝土中进行比对,易流型制备的高强混凝土具有良好的和易性,其倒置坍落度筒排空时间明显降低,证明混凝土粘聚性明显改善,混凝土施工性能也得到了提升。With mineral powder,fly ash and tailings fine powder as the main powder materials,the colloidal properties of mineral powder and tailings fine powder with different specific surface areas and the compatibility test with concrete admixtures were studied by grinding the mineral powder and tailings fine powder,and the microscopic morphology of the tailings fine powder was analyzed by SEM scanning method.According to the test results,combined with the unique effects of each powder material,the proportion of tailings powder is a fixed value of 50%,and other powder materials were mixed according to a certain proportion,to develop a composite admixture for high-strength concrete,and on this basis to improve its performance,independent research and development of a high-flow type high-strength concrete composite admixture characterized by high activity,high rheology and viscosity reduction.The results show that compared with a finished superfine composite admixture on the market,the 7d and 28d activity index of the composite admixture for high-strength concrete is increased by 7%and 3%respectively,and the mobility ratio was increased by 4%,which can better meet the needs of strength and workability of high-strength concrete.The composite admixture and the finished ultra-fine composite admixture are compared in C70,C80 and C90 high-strength concrete.The high-strength concrete prepared by the easy flow type has good workability,and its inverted slump cylinder empties time is significantly reduced,which proved that the cohesion of concrete was significantly improved and the construction performance of concrete was enhanced.

关 键 词：矿粉 粉煤灰 尾矿微粉 高强混凝土 复合掺合料 比表面积 胶砂性能 

分 类 号：TU528[建筑科学—建筑技术科学]