固硫灰与磨细固硫渣复掺用作混凝土掺合料的试验研究

Experimental Research on Mixed Circulating Fluidized Bed Coal Combustion Fly Ash and Ground Slag as Concrete Admixtures

试验将循环流化床燃煤固硫灰与磨细固硫渣按不同比例复掺,分析了复掺灰的各项性能,研究了复掺灰等质量替代粉煤灰对混凝土工作性能及强度的影响。结果表明,复掺灰安定性合格,固硫灰占比增大,复掺灰活性指数先增大后减小,需水量比逐渐增大,占比为40%时活性指数最高为84.23%,占比≤50%时,需水量比满足Ⅱ级灰要求;采用减水与保坍比例为1:0.8的高保坍减水剂,固硫灰占比40%的复掺灰配制的混凝土工作性能及强度均优于粉煤灰混凝土,与C30混凝土相比,复掺灰对C60混凝土的强度特别是早龄期强度的贡献更大。

Circulating fluidized bed coal combustion fly ash （CFBCF） and ground slag （GCFBCS） were admixed and the properties of the admixture were analyzed. The equal mass replacement of fly ash by admixture and its effects on workability and the strength of the concrete were also studied. The experimental results show that the soundness of admixture is qualified, the index of activity of admixture increases first and then decreases with increase of the FBCF ratio, on the other hand, water demand ratio increases gradually. The maximuth index of activity is 84.23% with the 40% FBCF ratio, the water demand ratio meet requirement of FAⅡ when the ratio is less than 50%. The workability and strength of concrete made of water reducer which ratio of water reducing agent and slump retaining agent is 1：0.8 and admixture which FBCF ratio is 40% is better than fly ash concrete. Compared with C30 concrete, the admixture contribution to strength especially early age strength is greater for C60 concrete.