人工砂石粉含量及MB值对自密实混凝土性能的影响及模型研究

Research on the effect of stone powder content and MB value for artificial sand on properties of self-compacting concrete and relational model

以胶凝材料、人工砂石粉含量、人工砂的MB值为主要影响因素,通过验证试验以及采用Design-Expert 7.0软件建立石粉、MB值与自密实混凝土性能关系模型,研究人工砂MB值、石粉含量及胶凝材料用量对自密实混凝土自密实性能的影响。研究结果表明以MB值、石粉含量作为人工砂技术要求,可有效控制人工砂自密实混凝土质量;人工砂的MB<1时,人工砂中石粉有利于改善混凝土的工作性,含量宜小于15%;人工砂的MB≥1时,混凝土工作性对人工砂中石粉含量变化较为敏感,含量宜小于5%;采用2F(I2-factor interaction)模型能较好地反映自密实混凝土填充性能(T50)与人工砂石粉含量、MB值及胶凝材料用量之间的关系。

With cementitious material,stone powder content and Methylene blue （MB） value for artificial sand as the major effect factor,the self-compacting concrete property model with stone powder content, MB value and binder content was established through verification experi- ments as well as the Design-Expert 7.0 software.The influence of MB values, stone powder content and binder content on self-compacting concrete have been studied.The results indicated that MB Value and stone powder content as the technical requirements of artificial sand, which could ef- fectively ensure the quality of self-compacting concrete.As artificial sand MB〈I, stone powder in artificial sand will help to improve workability of concrete,the content should be less than 15% ;And artificial sand MB/〉 1 ,the workability of concrete is more sensitive to changes of stone powder in artificial sand,the content should be less than 5%.2FI （2-factor interaction） model can reflect can reflect the relationship between filling ability of self-compacting concrete （T50） and stone powder content, MB values, binder content.