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Circular Economy
electron microscope (SEM) with magnifications of ×30, ×200 and ×500 was used.
Material
Control
35% FG
1111
70% FG
100% FG
Cement
Sand 0/0.5
Sand 0.5/1.6
Harina sílice
Silica fume
Granite powder
Water
Table 1. UHPC composition.
3. Results and conclusions
0.378 0.378 0.706 0.706 0.281 0.183 0.219 0.219
- 0.098 0.214 0.214 0.0125 0.0125 0.200 0.200
0.378 0.378 0.706 0.706 0.084 -
0.219 0.219 0.197 0.281 0.214 0.214 0.0125 0.0125 0.200 0.200
Superplasticizer
Steel fibres
Table 2 shows a summary of the results obtained in this work. The incorporation of granite cutting waste, as a replacement of micronized quartz, has not impact on the hardened density of UHPC. The variations are very small, less than 1.5%, and they are due to the variability of the experimental results.
The average compressive strength in all the mixes with granite waste is increased. This increase in compressive strength oscillates between 8.5%, for ratios of 35% and 70% and 4.5% for 100%.These slight increases can be due to the better compactness of the mixes when the granite cutting waste is incorporated.
The flexural strength increase when the substitution ratio is 35%, and even the values obtained for 100% substitution are acceptable. These good results obtained may be due to the better adhesion with the cement paste, as a consequence of the more irregular shape of the granite particles and the presence of the short steel fibres.
Table 2. Experimental results.
2410 2380 2390 2410 117,2 127,8 127,6 122,5 23,0 24,4 23,1 21,6
In view of the results obtained in this study, granite cutting waste, instead of the micronized quartz powder usually used, is a viable alternative for the manufacture of expectedly more sustainable UHPC.
4. Acknowledgment
The authors also want to thank the support to carry out this study to ArcelorMittal, Elkem, Basf, Sika AG, Granites Cabaleiro S.L. and the Ministry of Economy and Competitiveness of the Government of Spain.
5. References
European Union (2013), Decision 1386/2013/EU of the European Parliament and of the Council of 20 November 2013 on a General Union Environment Action Programme to 2020. Off. J. Eur. Union, Decision 1386 2013, 171–200.
Randl, N.; Steiner, T.; Ofner, S.; Baumgartner, E.; Meszoly, T. (2014), Development of UHPC mixtures from an ecological point of view. Construction and Building Materials. 67, 373–378.
S. Pyo and H. K. Kim (2017), Fresh and hardened properties of ultra-high performance concrete incorporating coal bottom ash and slag powder, Construction and Building Materials 131, 459-466.
Burroughs, J.F.; Shannon, J.; Rushing, T.S.; Yi, K.; Gutierrez, Q.B.; Harrelson, D.W. (2017), Potential of finely ground limestone powder to benefit ultra-high performance concrete mixtures. Construction and Building Materials. 141, 335–342.
Soliman, N.A.; Tagnit-Hamou, A. (2016), Development of ultra-high-performance concrete using glass powder—towards ecofriendly concrete. Construction and Building Materials. 125, 600–612.
Vaitkevicius, V.; Serelis, E.; Hilbig, H. (2014), The effect of glass powder on the microstructure of ultra high performance concrete. Construction and Building Materials. 68, 102–109.
Serie
Control
35% FG.
70% FG
100% FG
Density (kg/m3)
Compressive strength (MPa)
Flexural strength (MPa)
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