Combined effect of expansive and shrinkage reducing admixtures to obtain stable and durable mortars

被引:148
|
作者
Maltese, C [1 ]
Pistolesi, C [1 ]
Lolli, A [1 ]
Bravo, A [1 ]
Cerulli, T [1 ]
Salvioni, D [1 ]
机构
[1] Mapei SpA, I-20158 Milan, Italy
关键词
calcium oxide; expansion; expansive admixture; shrinkage; shrinkage reducing admixture;
D O I
10.1016/j.cemconres.2004.11.021
中图分类号
TU [建筑科学];
学科分类号
0813 ;
摘要
In order to improve the dimensional stability of cement based mortars, the effects produced on cement hydration of a shrinkage reducer (propyleneglycol ether based-SRA) and an expansive admixture (calcium oxide based-EXP) were investigated. Mortar samples (prepared without admixtures or with SRA or EXP or SRA and EXP) were compared through compressive strength measurements, water evaporation, restrained shrinkage and restrained expansion measurements. Setting time and free expansion were also detected on cement paste specimens. A synergistic effect on the shrinkage reduction was observed when the shrinkage reducing admixture and the expansive agent were used together. In order to clarify this phenomenon, the hydration of cement pastes containing these kinds of admixtures was followed by ESEM-FEG (environmental scanning electron microscopy-field emission gun), TG (thermogravimetry), specific surface area measurements (by BET-Brunauer-Emmet-Teller-method) and XRDS (X-ray diffraction spectroscopy). (c) 2005 Elsevier Ltd. All rights reserved.
引用
收藏
页码:2244 / 2251
页数:8
相关论文
共 30 条