粉煤灰水泥压实体早期水化和孔隙结构的演变  

Hydration and pore structure evolution of fly ash cement compacts at early age

作　　者：陆安群[1] 邓敏[1] 莫立武[1] 

机构地区：[1]南京工业大学材料科学与工程学院材料化学工程国家重点实验室,江苏南京210009

出　　处：《混凝土》2012年第11期24-27,共4页Concrete

基　　金：国家重点基础研究发展计划(2009CB623105)

摘　　要：利用压实粉体的方法制备粉煤灰水泥压实体,通过毛细吸收法、压汞法、氮吸附法、电子显微分析、非蒸发水和抗压强度的测定,研究粉煤灰水泥浆体早期水化和孔隙结构的演变。结果表明:随着水化进行,3 d龄期浆体水化显著,抗压强度迅速提高,后期水化变慢,抗压强度增长变慢。浆体孔隙率逐渐降低,3 d龄期内尤为明显;早期浆体中的大孔逐渐减少,小孔增多,最可几孔径向小孔径移动,7 d龄期后孔径变化缓慢。Compacted cement samples containing fly ash were prepared by compacting the cement and fly ash powders in a 25 mm×35 mm× 100 mm steel mould.The hydration process and the corresponding pore structure evolution were in investigated by using capillary absorption, MIP, BET, BSEM, measurement of chemical combination water and compressive strength.The results showed that hydration of fly ash cement compacts and compressive strength was rapidly developed within 3 d.At later age the hydration rate decreased and compressive strength increased relatively slowly.Porosity of fly ash cement compacts was reduced rapidly within 3 d.At early age,with the increasing hydration age,the volume of macro-pores in the cement decreased, whereas the volume of micro-pores increased.Moreover, the pore radius decreased with increasing hydration age within 7 d.After 7 d,the pore radius changed slowly.

关 键 词：水泥压实体 粉煤灰 孔结构 水化 

分 类 号：TU528.01[建筑科学—建筑技术科学]