Authors: Chunxiang Qian Mingfang Ba Xingun Guo Xiangyan Han
Publish Date: 2010/08/19
Volume: 25, Issue: 4, Pages: 682-686
Abstract
The coarse pore system interfacial transition zone ITZ between aggregate and paste matrix and volume fraction of unhydrated cement in concrete w/c=03 containing mineral admixtures were quantitatively characterized by the scanning electron microscopebackscattered electron SEMBSE image analysis technique The experimental results show that compound addition of slag and fly ash decreases the coarse porosity from 1017 to 374 and the threshold diameter of coarse pore size from 345 μm to 105 μm compared with concrete w/c=030 without mineral admixtures Moreover with compound addition of fly ash and slag the volume proportion of unhydrated cement in paste matrix is reduced by 30 the maximum amount of coarse pores in the ITZ between aggregate and paste decreases from 1311 to 557 and the thickness of ITZ is reduced by 37 compared with concrete without mineral admixtures
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