硅酸盐水泥熟料–煤矸石混合水泥的界面结构  

INTERFACE STRUCTURE OF PORTLAND COAL GANGUE BLENDED CEMENT

作　　者：刘贤萍[1] 王培铭[1] 

机构地区：[1]同济大学材料科学与工程学院,先进土木工程材料教育部重点实验室,上海200092

出　　处：《硅酸盐学报》2008年第1期105-112,共8页Journal of The Chinese Ceramic Society

基　　金：国家“973”计划(2001CB610704);国家“十一五”科技支撑计划(2006BAJ05B03)资助项目。

摘　　要：用环境扫描电镜和能谱仪研究了硅酸盐水泥和硅酸盐水泥熟料–煤矸石混合水泥的界面结构。结果表明:混合水泥中多孔的活化煤矸石和水泥水化产物发生二次反应消耗界面区大量氢氧化钙,生成水化硅酸钙(CSH)凝胶和钙矾石晶体,反应产物层从煤矸石表面向内部逐渐推进,逐渐将煤矸石的开口孔填满,未反应的煤矸石残核仍为多孔状。煤矸石中不同活性的SiO2反应生成的CSH凝胶形态不同,惰性SiO2作为微集料填充在硬化浆体中。煤矸石–反应产物的界面区结构非常致密,减弱了硅酸盐水泥中硬化浆体界面区间隙和氢氧化钙富集造成的不利影响。水化28d内混合水泥中煤矸石本身的强度和煤矸石–水化产物界面的强度均大于水化产物的强度。水化近1a的混合水泥中以长石类为主的多孔煤矸石残核的强度低于水化产物和煤矸石–水化产物界面强度,以石英为主的密实煤矸石的强度则高于水化产物和煤矸石–水化产物界面强度。The interface structure in Portland cement and Portland coal gangue cement were investigated by means of environmental scanning electron microscope and energy dispersive spectrometer. The results show that activated porous coal gangue in blended cement consumes much portlandite near the interface area when a secondary reaction occurs. Calcium silicate hydrate （CSH） and ettringite grow from the surface of the coal gangue; thus a reaction product layer grows from outside to inside and fills the open pores of the coal gangue. In blended cement after long periods of hydration, unreacted coal gangue remains porous. SiO2 in coal gangue with different activities can produce CSH of different morphologies, and inert SiO2 acts as micro-aggregate in hardened cement. The interface structure between coal gangue and the reaction product in blended cement is compacted, and thus weakens the disadvantage of the gap and enriched portlandite in Portland cement near the interface area. In blended cement, the strength of coal gangue and the interface between coal gangue and hydrates are higher than that of hydrates within 28 d hydration. The strength of unreacted porous coal gangue rich in feldspar is lower than that of the hydrates and the interface between coal gangue and hydrates and the compact coal gangue rich in quartz exhibits the opposite phenomenon after the hydration for 1 a.

关 键 词：煤矸石 混合水泥 水化 界面结构 

分 类 号：TU528[建筑科学—建筑技术科学]