【摘要】 利用设计的试验装置对不同水灰比道路混凝土的自收缩进行了测定,并用压汞法和光学显微镜结合Image Pro-plus软件分析了混凝土的孔级配和孔结构特征。试验建立了水灰比在0.38～0.44之间道路混凝土自收缩模型。机理研究表明,小于100 nm的毛细孔对自收缩起到至关重要的作用,变化用水量主要改变影响自收缩的小孔数量,而改变水泥用量对改变小孔数量、总气孔率、平均孔径和气孔间距系数有综合效应。更多还原

【Abstract】 The autogenous shrinkage of pavement concrete with different w/c ratios are measured by produced experimental setup,and these samples’ gradation and pore structure characteristics are analyzed by mercury intrusion method and optical microscope with Image Pro-Plus software.The autogenous shrinkage model of pavement concrete with 0.38-0.44 w/c ratio is established.The result of mechanism analysis shows that the pores with diameter less than 100 nm is vital important to autogenous shrinkage,varying water volume only changes the capillary number,and varying cement volume accordingly changes both capillary number,total porosity,average pore diameter and pore space factors.更多还原