两种不同形态纳米SiO_(2)对水硬性石灰性能的影响

Effect of two different forms of nano SiO_(2) on the properties of hydraulic lime

采用纳米SiO_(2)制备水硬性石灰材料,利用SEM、XRD和力学测试等技术手段对水硬性石灰材料的水化产物、微观结构和宏观性能等进行表征。研究了掺加0%,3%,6%,9%的纳米SiO_(2)的力学性能和表观形态;掺加的纳米SiO_(2)两种不同形态为气相型纳米二氧化硅粉状及凝胶态纳米硅溶胶。研究结果表明,粉状-凝胶状两种形态纳米SiO_(2)填充至水硬性石灰内部后,纳米SiO_(2)均可与水硬性石灰中的Ca(OH)_(2)发生水化反应,生成C-S-H凝胶并有效填充水硬性石灰砂浆内部;气相型粉状纳米二氧化硅相较于凝胶态纳米硅溶胶填充后力学强度要高,表观形态更好,更适合掺入至水硬性石灰中。

Nano SiO_(2) was used to prepare hydraulic lime materials,the hydration products,microstructure and macroscopic properties of hydraulic lime materials were effectively characterized by SEM,XRD and mechanical testing,and the mechanical properties and apparent morphology of 0%,3%,6%,and 9%were studied.The added nano SiO_(2) contains two different forms,including gas-phase nanosilica powder and gel-state nanosilica sol.The results show that after the nano SiO_(2),the nano SiO_(2) can react with Ca(OH)_(2) in the hydraulic lime to generate C-S-H gel to effectively fill the hydraulic lime mortar.The morphology and mechanical strength of the nanosilica powder are higher than the gel,which is more suitable for incorporation into the hydraulic lime.