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Advanced Construction Materials and Technologies
difference between the as-dry and water-saturated samples immersed in water for 24 h. The compressive strength for cured samples was measured according to the standard procedure UNE- EN 772-1:2011.
3. Results and conclusions
The addition of BC increased bulk density of geopolymers. The bulk density of the control
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geopolymers was 1270 kg / m , increaseasing up to 1500 kg / m with the incorporation of 25
wt.% of BC and up to 1670 kg / m3 with the incorporation of 100 wt.% of BC. Water absorption of the control geopolymers was 30.9 %. The incorporation of BC produced a significant decrease in water absorption. This indicated a lower open porosity in geopolymers that contains black clay. The compressive strength of the reference samples (with 100 wt %Metakaolin ) was 17.5 MPa. The addition of up to a 75 wt% of BC produced a slight decrease in compressive strength, decreasing up to 15.67 MPa. However, the addition of 100 wt % of waste produced a significant decline in compressive strength, up to 10.20 MPa.
The data indicated that it is possible to substitute 75 wt% of MK for BC by obtaining geopolymers with adequate physical and mechanical properties
4. Acknowledgment
This work has been funded by the Project “Development and characterization of new geopolymers composites based on waste from the olive industry. Towards sustainable construction” (MAT2017-88097-R), FEDER/Ministry of Science, Innovation and Universities, State Research Agency.
5. References
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M.I.M. Alzeer, K.J.D. Mackenzie, R.A. Keyzers, Porous aluminosilicate inorganic polymers (geopolymers): a newclass of environmentally benign heterogeneous solid acid catalysts. Appl.Catal. A-Gen. 524 (2016) 173- 181.
M. Alshaaer, S.A. Mallouh, J. Al-Kafawein, Y. Al-Faiyz, T. Fahmy, A. Kallel, F. Rocha, Fabrication, microstructural and mechanical characterization of Luffa Cylindrical Fibre – Reinforced geopolymer composite, Appl. Clay Sci. 143 (2017) 125-133.
K. Komnitsas, D. Zaharaki, Geopolymerization: a review and prospects for the minerals industry. Miner. Eng. 20 (2007) 1261-1277.
C.L. Hwang, T.P. Huynh, Effect of alkali-activator and rice husk ash content on strength development of fly ash and residual rice husk ash-based geopolymers, Constr. Build. Mater. 101 (2015) 1–9.
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