机制砂MB值对轨道交通工程用混凝土性能的影响  

Effect of MB Value of Manufactured Sand on Performance of Concrete Used in Rail Transit Engineering

作　　者：陈秀鸣 陈洪[2] 潘玮璠 史星祥[2] 郭耀雄 许志扬 张立力 CHEN Xiu-ming;CHEN Hong;PAN Wei-fan;SHI Xing-xiang;GUO Yao-xiong;XU Zhi-yang;ZHANG Li-li(Suzhou Rail Transit Group Co.,Ltd.,Suzhou 215000,China;Suzhou Concrete and Cement Products Research Institute Co.,Ltd.,Suzhou 215004,China)

机构地区：[1]苏州市轨道交通集团有限公司,江苏苏州215000 [2]苏州混凝土水泥制品研究院有限公司,江苏苏州215004

出　　处：《混凝土与水泥制品》2022年第4期19-24,共6页China Concrete and Cement Products

基　　金：苏州市轨道交通集团有限公司科研项目(SZZG06YJ1060007);江苏省社会发展项目(BE2020780);苏州市民生科技项目(SS2019019)。

摘　　要：研究了不同母岩岩性、石粉含量、泥粉含量和类型与机制砂MB值的关系,确立了轨道交通工程用混凝土性能的主要影响因素,以实现对机制砂MB值的定量调控。以轨道交通工程典型C20、C35和C50混凝土为研究对象,开展了MB值对其工作性、抗压强度和抗氯离子渗透性的影响研究。结果表明:MB值主要取决于机制砂中的泥粉含量和类型,与母岩岩性和石粉含量的关系不大;MB值的增加会显著降低混凝土的工作性,混凝土强度等级越高对工作性的敏感程度越高,且对掺聚羧酸减水剂混凝土工作性的劣化效果比掺萘系减水剂更显著;当MB值在0.85~2.00之间时,三种混凝土的抗压强度均有不同程度的提升,达到最大值后,抗压强度出现不同程度的下降,C50混凝土的下降幅度最大;适当的MB值可以提高C35混凝土的抗氯离子渗透性;C50混凝土的抗氯离子渗透性会随着MB值的提高而逐渐降低。The relationship between different parent rock lithology,stone powder content,mud powder content and type and MB value of manufactured sand was studied,and the main influencing factors of concrete performance for rail transit engineering were established,so as to realize quantitative regulation of MB value of manufactured sand.Taking the typical C20,C35 and C50 concrete of rail transit engineering as the research object,the effect of MB value on workability,compressive strength and resistance to chloride ion permeability of concrete was studied.The results show that the MB value mainly depends on the content and type of mud powder in the manufactured sand,and has little relationship with the lithology of the parent rock and the content of stone powder.The increase of the MB value will significantly reduce the workability of concrete,and the higher the concrete strength grade,the higher the sensitivity to workability,and the deterioration effect of polycarboxylate superplasticizer on concrete workability is more significant than that of naphthalene-based superplasticizer.When the MB value is between 0.85 and 2.00,the compressive strengths of the three concretes are improved to different degrees,and after reaching the maximum value,the compressive strength decreases to varying degrees,and the C50 concrete has the largest decrease.Appropriate MB value can improve the chloride ion permeability resistance of C35 concrete.The chloride ion permeability resistance of C50 concrete will gradually decrease with the increase of MB value.

关 键 词：机制砂 亚甲蓝值 泥粉 轨道交通工程 工作性 

分 类 号：TU528[建筑科学—建筑技术科学]