混合砂比例对T梁C55混凝土性能的影响

Effect of Mixed Sand Ratio on Performance of T-beam C55 Concrete

该文针对肯尼亚内马铁路沿线缺乏河砂的现状和采用机制砂配制高强混凝土粘度过大的问题,通过混凝土含气量、容重、坍落度和抗压强度研究了机制砂和河砂混合砂中的混合比例对混凝土性能的影响。结果表明:随着混合砂中机制砂比例的增加,混凝土含气量逐渐下降,混凝土容重和抗压强度呈现增大趋势,保持混凝土坍落度在(180±10)mm,减水剂用量随着机制砂比例的增大而增加,即使减水剂用量增加,采用机制砂比例较高的混合砂配制的混凝土坍落度也呈下降趋势。

In view of the problem such as lacking river sand along Kenya Nairobi-Naivasha Standard Gauge Railway Project and excessive viscosity of high strength concrete prepared by manufactured sand,this article studies effect of mixing ratio of manufactured sand and river sand on concrete properties based on gas content in concrete,volume weight,slump and compressive strength.The results show that as proportion of manufactured sand increases in mixed sand：gas content in concrete decreases gradually,volume weight and compressive strength of concrete are increasing,and the slump of concrete is kept at（180±10）mm;the amount of water reducing agent also increases,in addition,even if the amount of water reducing agent is increased,slump of concrete prepared by mixed sand with a higher proportion of manufactured sand declines.