摘要
研究了轻骨料掺量不同的混凝土当掺与不掺粉煤灰时不同龄期的抗氯离子扩散性能以及骨料附近水化产物中Ca(OH)2含量和水泥石孔结构的变化情况。结果表明:随着混凝土中轻骨料掺量的增加,掺加了粉煤灰的浆体28～90d期间水化产物中Ca(OH)2含量的减少幅度大于未掺粉煤灰试样的,且水泥石孔隙率有所降低,孔径细化,掺入粉煤灰后轻骨料掺量越多的试样孔径细化越显著,可见轻骨料后期返出的水分起到了自养护作用,保证了粉煤灰的水化。在混凝土中掺入适量的轻骨料,其返水特性与粉煤灰二次水化反应的协同作用使得混凝土后期抗渗性能显著提高,优于普通骨料混凝土。
Concretes containing different fractions of lightweight aggregate （LWA） and fly ash （FA） were prepared. The Ca（OH）2 content and pore structure of the paste around aggregate as well as the chloride permeability of concrete were investigated. The results show that, with the increase of the LWA content, an increase of the curing age from 28 d to 90d has made the decrease of the Ca（OH）2 content of the paste mixed with FA increases gradually as compared to that of the pasted mixed without FA, and the hardened cement paste appears a structure with a lower porosity and finer pores. The pore size of specimen made at a higher LWA content becomes smaller due to the addition of the FA. It is indicated that the water release effect of the LWA can play a role for the internal curing and ensure the hydration of the FA at later age. The impermeability of concrete prepared with the LWA and FA also gains more improvement as compared to normal weight concrete in long term.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2009年第7期1239-1243,共5页
Journal of The Chinese Ceramic Society
基金
交通部西部交通建设(200331882008)资助项目
关键词
轻骨料
粉煤灰
返水
孔结构
二次水化
lightweight aggregate
fly ash
water release
pore structure
secondary hydration
