Alkali activated metakaolin with high limestone contents - Statistical modeling of strength and environmental and cost analyses

被引:98
作者
Perez-Cortes, Pedro [1 ]
Escalante-Garcia, J. Ivan [1 ]
机构
[1] Cinvestav Saltillo, Saltillo, Coahuila, Mexico
关键词
Geopolymer; Alkali activated cements; Limestone; Metakaolin; Surface response method; Sustainability; SODIUM-SILICATE ACTIVATION; GREENHOUSE-GAS EMISSIONS; GEOPOLYMER CONCRETE; CURING TEMPERATURE; FLY-ASH; MECHANICAL-PROPERTIES; COMPRESSIVE STRENGTH; CEMENT; DEHYDROXYLATION; MICROSTRUCTURE;
D O I
10.1016/j.cemconcomp.2019.103450
中图分类号
TU [建筑科学];
学科分类号
0813 ;
摘要
Alkaline binders of metakaolin (MK) and limestone (LS) are promising sustainable cementitious new alternatives; however, systematic studies are required to understand them to take them to industrial level, This study presents the modeling and optimization of strength using the surface response method of such binders with up to 80%LS and molar ratios of Na/Al = 0.5-1.86 and Si/Al = 1.81-3.13. A quadratic model (R-squared = 94.31%) indicated an optimal formulation of 32.32%LS, Na/Al = 1.34 and Si/Al = 2.96 with a predicted, and experimentally corroborated, 28-day strength of 70 +/- 3.9 MPa, which was higher than references of 100%MK and blended Portland cement (BPC). The microstructural features were in agreement with the high strength. The analyses of cost, CO2-emissions and energy demand indicated pastes of 100%MK are better than BPC only regarding CO2-emissions, while blends with %LS>32.12% were better in all indicators relative to both of the former. As limestone is abundant, cheap, reduces alkali demand and do not require calcination, these binders are actually sustainable.
引用
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页数:13
相关论文
共 85 条
[11]   Influence of the long term curing temperature on the hydration of alkaline binders of blast furnace slag-metakaolin [J].
Burciaga-Diaz, Oswaldo ;
Gomez-Zamorano, Lauren Y. ;
Ivan Escalante-Garcia, Jose .
CONSTRUCTION AND BUILDING MATERIALS, 2016, 113 :917-926
[12]   Geopolymers based on a coarse low-purity kaolin mineral: Mechanical strength as a function of the chemical composition and temperature [J].
Burciaga-Diaz, Oswaldo ;
Ivan Escalante-Garcia, Jose ;
Gorokhovsky, Alexander .
CEMENT & CONCRETE COMPOSITES, 2012, 34 (01) :18-24
[13]  
Cancio Diaz Y., 2017, DEV ENG, V2, P82, DOI [10.1016/j.deveng.2017.06.001, DOI 10.1016/J.DEVENG.2017.06.001]
[14]  
Cardarelli Francois., 2008, Materials Handbook: A Concise Desktop Reference, DOI [10.1007/978-1-84628-669-8, DOI 10.1007/978-1-84628-669-8]
[15]   The effect of limestone on sodium hydroxide-activated metakaolin-based geopolymers [J].
Cwirzen, Andrzej ;
Provis, John L. ;
Penttala, Vesa ;
Habermehl-Cwirzen, Karin .
CONSTRUCTION AND BUILDING MATERIALS, 2014, 66 :53-62
[16]  
Davidovist J., 1985, US Patent, Patent No. [4509985, 4,509,985]
[17]   GEOPOLYMERS - INORGANIC POLYMERIC NEW MATERIALS [J].
DAVIDOVITS, J .
JOURNAL OF THERMAL ANALYSIS, 1991, 37 (08) :1633-1656
[18]  
Davidovits J., 1982, Google Patents. US Patent, Patent No. [4,349,386, 4349386, US4349386A]
[19]  
Davidovits J., 1994, 1 INT C ALK CEM CONC, P131
[20]  
Davidovits J., 1984, US Patent, Patent No. [USP 4472199, 4472199, US4472199A]