粒径对粉煤灰基地聚物抗压强度的影响

Influence of particle size on compressive strength of fly ash based-geoploymer

为提高粉煤灰的综合利用,以工业废弃物粉煤灰为主要原料,通过碱激发制备粉煤灰基地聚物,研究了粉煤灰的粒径及粒径分布对粉煤灰基地聚物抗压强度的影响。试验结果表明:对于单峰分布不同粒径的粉煤灰来说,随着D_(50)粒径的减小,粉煤灰基地聚物的28 d抗压强度随之显著升高,早期抗压强度也随之大幅提高;对于相同D_(50)粒径下单峰和双峰分布的粉煤灰来说,单峰分布的粉煤灰基地聚物的抗压强度略低于双峰分布粉煤灰基地聚物的抗压强度;进而证明D_(50)粒径是影响粉煤灰基地聚物的因素之一,通过调节粒径分布可以改善抗压强度,为进一步控制粉煤灰基地聚物的抗压强度提供了理论基础。

To make full use of fly ash,a fly ash based-geoploymer was prepared using alkali activated fly ash as raw material.The influence of particle size and distribution of fly ash on compressive strength of fly ash based-geopolymer was studied.The results showed that,for different particle size of fly ash with unimodal distribution,with the decrease of median diameter D_（50）,early compressive strength and 28 days compressive strength of fly ash based-geopolymer significantly increased.For same D_（50） with unimodal and bimodal distribution of fly ash,the compressive strength of geopolymer using fly ash with unimodal distribution as raw material was slightly lower than that of geopolymer using fly ash with bimodal distribution.the results also indicated that particle size（ D_（50）） was one of the important factors to affect the performance of fly ash based-geopolymer.Therefore,the compressive strength of fly ash based-geopolymer could be improved by adjusting the particle size and distribution of fly ash,the research provided a theoretical basis to control the compressive strength of fly ash based-geopolymer.