粉煤灰和硅灰取代率对碱矿渣混凝土力学性能影响分析OA北大核心CSTPCD

In order to study the effect of fly ash and silica fume contents on the properties of alkali-activated slag-based concrete(AASC),the changes in setting time,cubic compressive strength,cubic splitting tensile strength,flexural strength,and elastic modulus of AASC were investigated by conducting tests on setting time and basic mechanical properties.Based on the test results,a regression analysis method was used to establish the conversion relationship equation of cubic splitting tensile strength,flexural strength,and elastic modulus with cubic compressive strength,and the effect of fly ash and silica fume on the properties of AASC was revealed according to the microstructure and phase composition.The results show that the fly ash and silica fume can prolong the setting time of AASC;the mechanical property indicators of AASC tend to strengthen and then weaken with the increase in the contents of fly ash and silica fume,and the optimal contents of fly ash and silica fume are 20%and 10%,respectively.The proposed empirical formulae for cubic splitting tensile strength,flexural strength,and elastic modulus of AASC have a high fitting precision.The appropriate contents of fly ash(silica fume≤20%)and silica fume(silica fume≤10%)can promote the hydration reaction of AASC and the denser microstructures.