氧化石墨烯对高掺量粉煤灰水泥基材料性能的影响及机理

Influence and mechanism of GO on the property of high content fly ash cement-based material

研究了氧化石墨烯(GO)对高掺量粉煤灰水泥基材料(粉煤灰掺量50%)性能的影响。结果表明,随着GO掺量的增加,水泥基材料的凝结时间逐渐缩短。掺入1%的GO,其初凝和终凝分别缩短了50min和55min;水泥基材料的抗折强度随着GO掺量增大先增加后减小,当GO掺量为0.6%时,水泥基材料7d和28d抗折强度和抗压强度最佳,相对于空白组分别提高了34%和8.7%,但GO对水泥基材料抗压强度没有显著影响。采用XRD和SEM分析了GO作用机理,发现GO能够促进水泥矿物的早期水化反应,进而加快粉煤灰的早期火山灰反应。此外,GO还可以充当模板调控作用,生成具有花瓣状结构的水化产物。

The effect of graphene oxide(GO)on the properties of high content fly ash cement-based materials(fly ash content 50%)was studied.The results shown that with the increase of GO content,the setting time of the materials was gradually shortened.When adding 1% GO,the initial setting and final setting were shortened by 50 min and 30 min,respectively When the GO content was 0.6%,the 7 dand 28 dflexural strength and compressive strength of the materials were the best,which were increased by 34% and 8.7%respectively compared with the blank group,but GO had no significant effect on the compressive strength of the materials.The mechanism of GO was analyzed by XRD and SEM.It was found that GO could promote the early hydration reaction of cement clinker minerals,and then accelerated the early pozzolanic reaction of fly ash.In addition,GO can also act as a template to generate petal like hydration products.