Effect of Fillers on High Temperature Shrinkage Reduction of Geopolymers

Abstract

Geopolymers produced from aluminosilicate materials such as metakaolin and coal ash react with alkali activators and show higher fire resistance than portland cement, due to amorphous inorganic polymer. The percentage of thermal shrinkage of geopolymers ranges from less than 0.5 % to about 3 % until 600 o C, and reaches about 5 ~ 7 % before melting. In this study, geopolymers paste having Si/Al = 1.5 and being mixed with carbon nanofibers, silicon carbide, pyrex glass, and vermiculite, and ISO sand were studied in order to understand the compressive strength and the effects of thermal shrinkage of geopolymers. The compressive strength of geopolymers mixed by carbon nanofibers, silicon carbide, pyrex glass, or vermiculite was similar in the range from 35 to 40 MPa. The average compressive strength of a geopolymers mixed with 30 wt.% of ISO sand was lowest of 28 MPa. Thermal shrinkage of geopolymers mixed with ISO sand decreased to about 25 % of paste. This is because the aggre-•

Machine Learning Based Reactivity Prediction of Fly Ash Type F Produced from South Korea

“…This will be referred to as model B. As data for model B, 62 FA samples from 17 papers were collected (Cho and Lee 2019;Cho et al 2016aCho et al , b, 2019Jang and Lee 2016;Jeon et al 2015Jeon et al , 2018Jung-Il et al 2020;Kang et al 2013;Kim et al 2017Kim et al , 2018Moon et al 2016;Oh et al 2014Oh et al , 2015Park and Choi 2019;. The model B data, like the model A data, comprises the XRF chemical composition of bulk FA as input features, and the amount of aluminosilicate glass determined by QXRD as the output feature.…”