石灰-石膏-粉煤灰水泥浆体的水化机理研究  

Study on hydration mechanism of lime-gypsum fly ash cement paste

作　　者：徐子芳[1] 张明旭[1] 许海仙[1] 

机构地区：[1]安徽理工大学材料科学与工程学院,淮南232001

出　　处：《环境工程学报》2009年第10期1879-1884,共6页Chinese Journal of Environmental Engineering

基　　金：2008年度安徽省高校省级自然科学研究项目(KJ2008B274)

摘　　要：通过增钙法对粉煤灰水泥浆体的凝结时间、水化放热和力学性能的测定,以及采用差示-热重分析、扫描电镜、X射线衍射,研究了在有石灰、石膏时不同掺量粉煤灰水泥浆体的水化机理。结果表明:早期水化性能弱,后期持久。随粉煤灰掺量增加,浆体的凝结时间延长,水化热减少,高掺超过40%时龄期强度下降明显;早期水化产物主要为:大量的水化硅酸钙凝胶(C-S-H),未水化的硅酸钙(C3S、C2S),少量的钙矾石(AFt、AFm)和氢氧化钙Ca(OH)2,后期在石灰-石膏的活性效应和填充效应的激发下,水化产物主要为:Ca(OH)2、AFm。Ca(OH)2与AFm及少量的C-S-H填充在水泥孔隙中且相互交联,改善了粉煤灰水泥浆体强度。According to differential scanning calorimeter-thermal gravity, scanning electron microscope,X- ray diffraction and the measurement of the setting time, the hydration heat and the mechanical properties of the fly ash cement paste by adding calcium, the hydration mechanism of the fly ash cement paste with lime-gypsum and different addition of fly ash was studied. The results show that hydrating capacity of early age is weak, but long-term is lasting; along with the increase of fly ash, the setting time of paste prolongs and the hydration heat decreases; when the dosage of fly ash is more than 40% , the compressive strength decreases evidently. The main early hydration products are a large quantity of calcium silicate hydrate gel （C-S-H） , calcium silicate with- out hydration （C3S,C2S） ,a small quantity of ettringite （AFt,AFro） and calcium hydroxide Ca（OH）2. Under the activation of the activity effect and the filling effect of lime-gypsum, the main hydration products at a later age are Ca （OH）2 and AFro. Ca （OH）2, AFro and a little bit C-S-H fill the pore space and crosslink mutually, which improves the strength of fly ash cement paste.

关 键 词：石灰-石膏 粉煤灰水泥 水化性能 激发剂 

分 类 号：X705[环境科学与工程—环境工程]