采用化学滴定法系统研究了水胶比为0.4煤矸石掺量分别为0％、20％、30％和40％的水泥-煤矸石凝胶体系对氯离子结合能力的影响规律.通过XRD、DSC和TG-DTG方法,研究其结合机理.结果表明:随煤矸石掺量的增大,结合能力呈现先增加后降低趋势,最佳掺量为30％o超过此值,经DSC和XRD微观分析表明,Friedel盐(简称F盐)含量因水泥浆体的初级水化产物CH含量不足,影响了煤矸石的二次水化反应的发挥而下降.活化煤矸石对氯离子的结合能力一方面因其高铝酸盐含量稀释了硫酸盐,增加AFm相生成,另一方面因其比表面积较大,结构疏松对氯离子有一定吸附作用,同时火山灰效应的发挥生成较多的C-S-H凝胶和水化铝酸盐相,进而促进F盐的形成.%The binding capacity and mechanisms of chloride ion in hydrated cementitious paste ( w/b = 0. 4) with 0% ,20% , 30% and 40% mass fraction of activated coal gangue is respectively investigated by chemical titration analysis, X-Ray Diffractometry ( XRD) , Differential Scanning Calorimetry ( DSC ) and Thermo-gravimetry-Differential Thermogravimetry (TG-DTG). Results indicate that chloride binding capacity of cement-based materials is increased initially and then decreased with increasing of activated coal gangue dosage. Friedel' salt content is dropped due to lack of portlandite in the number of initial hydrated products of cement paste so that influenced second hydration reaction of coal gangue . The reason of activated coal gangue bound chloride ion is as follows. Firstly, coal gangue with higher aluminates content dilutes sulphates and then adds the formation of AFm phase. Secondly, part of chloride ion is absorbed for its higher specific surface area and loose structure. C-S-H gel and hydrated aluminates phase content is enhanced with the pozzolanic effect of activated coal gangue,which is the last, and also the most important for the formation of Friedel' s salt.
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