2024, Volume 70(74), Issue 1 (January), pp. 9 - 22

Preserving The Mechanical Properties of Metakaolin-Based Geopolymer Composite Exposed to Thermal Stress by Using Refractory Filler Wastes

LUCIAN PĂUNESCU, Daily Sourcing & Research SRL Bucharest, Romania, lucianpaunescu16@gmail.com
ADRIAN IOANA, National University of Science and Technology POLITEHNICA Bucharest, Faculty of Science and Materials Engineering, Romania
ENIKÖ VOLCEANOV, National University of Science and Technology POLITEHNICA Bucharest, Faculty of Science and Materials Engineering, Romania, Metallurgical Research Institute SA Bucharest, Romania

pages 9 - 22   Download
DOI: 10.5281/zenodo.11144762

Abstract
Metakaolin-based geopolymer composite with addition of refractory filler wastes (super-aluminous concrete and silica fire brick) recycled from heating oven demolition was designed and tested under thermal stress conditions at temperatures up to 900°C. The method of alkaline activating patented by Davidovits was applied. The originality of the work consists in choosing the super-aluminous concrete waste from the demolition as the main raw material of the process, increasing the heat treatment temperature to 90°C, and adopting the storage for a much longer period (28 days). Tests to thermal stress by exposure to 600 and 750°C showed the favourable influence of the addition of refractory fillers on preserving the mechanical stability of the geopolymer composite. The loss of compression and flexural resistance after exposure to 900°C compared to the reference sample is acceptable for using this technique in the case when the stability at high temperature is required.
Keywords: geopolymer composite, refractory filler waste, metakaolin, thermal stress, mechanical strength.