机制砂清水自密实混凝土材料设计与工程应用研究

Design and Engineering Application of Fair-faced Self-compacting Concrete with Manufactured Sand

文中基于体积法,通过级配优化、流变改性等手段,设计符合项目要求的机制砂清水自密实混凝土,研究关键因素对FFSCC工作性能的影响。结果表明,粗集料含量增加会对FFSCC工作性形成负面影响,细集料含量较小时,砂率增长有利于工作性,含量较大时不利。FFSCC强度早期偏弱,后期增幅较大,抗渗性和体积稳定性不如常规清水混凝土,抗冻性、材料及应用成本具有优势。

In order to meet the needs of engineering construction,this study based on volume design,through aggregate grade optimization and cement paste rheology modification,have designed the fair-faced self-compacting concrete(FFSCC)with manufactured sand.The influence of key factors on workability of FFSCC was studied:the increase of coarse aggregate will have a negative impact on workability of FFSCC;when the content of fine aggregate is small,the increase of sand rate is conducive to workability,and when the content is large,it is unfavorable.The strength of FFSCC is weak in the early stage,but increases greatly in the later stage.The impermeability and volume stability are not as good as that of conventional fair-faced concrete,and the frost resistance and material and application cost have advantages.