高温养护对复合胶凝材料水化程度及微观形貌的影响

Effect of high temperature curing on hydration degree and micro-morphology of complex binders

采取对化学结合水含量和粉煤灰反应程度的测定、形貌观察和能谱测试等手段对高温养护制度下复合胶凝材料水化程度及硬化浆体微观形貌进行研究。研究结果表明:高温养护的热激发作用增强了粉煤灰的火山灰活性,显著提高了早龄期体系的水化程度,而且能使粉煤灰颗粒表面产生更多水化产物,促使浆体结构更加致密;但高温养护对C-S-H凝胶钙硅质量比(钙硅比)的影响不显著,而且对后期浆体水化程度的提高以及微观结构的改善无较大贡献。

The hydration degree and microstructure of complex binders during high temperature curing were studied by determining the non-evaporable water content and the reaction degree of fly ash,observing the micro-morphology and testing spectrum.The results show that heat activation obviously enhances the pozzolanic reaction of fly ash,which elevates the early hydration degree of complex binders remarkably.More hydration products are generated on the surface of fly ash particles,which makes the microstructure of pastes more denser than that cured at room temperature.However,high temperature curing has insignificant influence on the mass ration of CaO to SiO2 of C-S-H gel in pastes and contributes little to the improvement of the later hydration degree and microstructure of complex binders.