纳米C-S-H对粉煤灰/矿粉双掺混凝土性能的影响

Influence of Nano C-S-H on Performance of Fly Ash/Slag Mixed Concrete

通过强度测试、电通量测试研究了纳米水化硅酸钙(n-C-S-H)对粉煤灰/矿粉双掺混凝土性能的影响,对该体系的水泥净浆进行了水化热测试,分析了n-C-S-H对其的影响机理。结果表明,n-C-S-H对混凝土性能的影响随粉煤灰和矿粉比例的变化而变化,当混凝土中粉煤灰比例降低,矿粉比例增加后,n-C-S-H最佳掺量会适当降低,而当n-C-S-H掺量过高时,对应混凝土的28 d强度和电通量都要低于空白组。相较于粉煤灰比例高的水泥浆体,矿粉比例高的水泥浆体水化放热速率更快并且水化热更高,n-C-S-H掺量越高,两者之间的差异越大。

The influence of nano hydrated calcium silicate(n-C-S-H)on the performance of fly ash/slag mixed concrete was investigated using concrete strength test and electric flux test.Meanwhile,the hydration heat of the cement paste was tested and the influence mechanism of n-C-S-H was analyzed.The results indicate that the influence of n-C-S-H on concrete changes with the proportion of fly ash and slag.When the proportion of fly ash in concrete decreases and the slag increases,the optimum content of n-C-S-H decreases.The 28 d strength and electric flux of concrete are lower than that of blank group while the content of n-C-S-H is higher.Compared with a high proportion of fly ash,the hydration exothermic rate of cement paste with a high proportion of slag is faster and the hydration heat is higher.When the content of n-C-S-H is higher,the difference between the two is greater.