粉煤灰、矿粉对高性能混凝土渗透性的影响

Effect of fly ash and slag on the permeability of high performance concrete

采用氯离子扩散系数、电通量、气体渗透性系数以及毛细管吸附4种渗透性测试方法研究粉煤灰和矿粉对高性能混凝土的渗透性能影响规律。结果表明粉煤灰掺入后,对混凝土的早期渗透性能起负效应,对混凝土的后期渗透性能起正效应;矿粉掺入后不但能改善混凝土的早期渗透性能,而且也能提升混凝土后期的抗渗性能;3种混凝土的氯离子扩散系数与电通量、气体渗透性,毛细管吸水率之间存在一定的相关性。

Four test methods of permeability, such as chloride diffusion coefficient, electric flux, gas permeability coefficient and capil-lary absorption rate, were used to study permeability of concrete with in fly ash and slag.Experimental results showed that, compared to the reference concrete, the incorporation of 30% fly ash can increase the concrete permeability at early days, and can decline the concrete per-meability at later days.Under the same conditions, incorporation of 45% slag can improve the impermeability of concrete at the all testing ages.Chloride diffusion coefficient showed good correlation with electric flux, gas permeability coefficient and capillary absorption rate, which concrete with or without mineral admixtures.gth; test; performance; application.