关键词: 碱激发矿渣混凝土;膨胀剂;补偿收缩;微观结构分析

Abstract: The shrinkage compensation performance of alkali-activated slag concrete ( AASC ) with lime and cacium sulphoaluminate expansive admixture ( EA ) of different content ( 0%, 2%, 4%, 6% and 8%) under the condition of free and semi sealed constraints was texted .On this basis , microstructural analysis of hardened pastes of EA react with water , NaOH solution and water glass solution individually and alkali-activated slag with diferent EA content was invtstigate .Shrinkage performance test results show that the AASC specimens'shrinkage are all reduce under two conditions , and the reduction degree increases with the increase of EA content .When the content of EA is 8%the shrinkage is 3.0 ×10 -4μεunder free condition and 4.0 ×10 -4 με under semi sealed conditon .Indicated that the EA has a good shrinkage-compensation capability , and the effection is more significant under the semi sealed condition . Microstructural analysis results show that the hydration products of ettringite and calcium hydroxideare are all tested in the EA pastes , but in the alkali-activated slag past only tested calcium hydroxideare . Indicated that in the AASC with EA play the role of shrinkage-compensation capability is main because the hydration products of Ca ( OH) 2 .

Key words: alkali-activated slag concrete;expansive agent;shrinkage compensation;microstructural analysis