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TECHNICAL PAPER

the mineralogy of granite, river sand, and limestone before REFERENCES
any exposure and after exposure to 550°C, with or without the
presence of liquid sodium and to a high alkaline NaOH bath [1] Alexander, M., and Mindess, S. (2005). “Aggregates in
at 80°C for 14 days. These types of chemical analysis help in Concrete”, Taylor and Francis, Abingdon, Oxfordshire,
quantifying mineral phases formed during different exposures, London, and New York.
based on prevailing reaction kinetics, and eventually help in [2] Mehta, P. K., and Monteiro, P. J. M. (2006). “Concrete -
developing performance indices for special applications of microstructure, properties and materials", Third edition,
concretes [91] . The McGraw-Hill, New York.
[3] Schifman, J. (2017) “The rock solid history of concrete”,
8. CONCLUSIONS Popular mechanics, October 12, 2017, https://www.

This paper reviewed the mineralogy of aggregates used in popularmechanics.com/technology/infrastructure/a28502/
concrete with respect to their geo-chemistry. The relevance rock-solid-history-of-concrete/, visited on 8/11/2018.
of mineralogical characteristics of aggregates are discussed [4] Courland, R. (2011) “Concrete planet: The strange and
with respect to their engineering properties. Furthermore, the fascinating story of the world’s most common man-made
influence of mineralogical characteristic on concrete properties material”, Rowman and Littlefield, First edition.
with the help of geo-chemical, and petrographic interpretations
are addressed; along with state of art colour atlas on minerals [5] Szabó, Hidalgo, L. I., Císcar, J. C., A. Soria, A., and Russ,
in thin sections related to aggregates. The discussion on the P. (2003). “Energy consumption and CO 2 emissions from
influence of mineralogy on properties like shape, and texture the world cement industry”, European Commission Joint
of aggregates, their physical properties such as hardness, and Research Center (DGJRC). http://www.bvsde.paho.org/
density, and weathering potential are later correlated to their bvsaia/fulltext/energy.pdf.
performance properties. Strength contribution to concrete by [6] Poole, A. B., and Sims, I. (2016). “Concrete petrography-a
various aggregate types are discussed as well as the difference hand book of investigating techniques”, CRC Press, Taylor
in strength contribution to various types of concrete – normal and Francis Group, London
and high strength. It is reported that for concretes with strength
more than 60 MPa, aggregates perform better by contributing [7] Deer, W. A., Howie R. A., and Zussman, J. (1992). “An
their best to the strength owing to the absence of a weak ITZ introduction to the rock forming minerals”, Second
in the system. On reviewing a range of durability issues such as edition, Pearson, Prentice Hall, New York
alkali aggregate reaction, freeze-thaw, corrosive environments [8] Dana, E. S. (1885). “A text-book of mineralogy: with
for the influence of the aggregate mineralogy in them, the SEM an extended treatise on crystallography and physical
and petrographic images of aggregates clearly demonstrate mineralogy”, Eleventh edition, John Wiley and sons,
the reason for the respective performances. Understanding New York.
a correlation between the mineralogy, physico-mechanical
properties of aggregates, and the corresponding durability [9] Perkins, D. (2002). “Mineralogy”, Second edition, Pearson
performance of concrete can facilitate judicious and optimum Education, Singapore.
selection of aggregates in specific exposure cases. The thermal [10] Johnsen., O. (2002). “Minerals of the world”, Princeton
properties of various aggregates (siliceous, calcareous and University Press, New York.
silico-calcareous) are also revisited with the help of thin section [11] Mackenzie, W. S., Adams, A. E. (2009). “A colour atlas of
images, giving evidence of various mechanisms associated with rocks and minerals in thin section”, Manson Publishing
the aggregates at different temperatures. The paper concludes Ltd., U.K.
by providing a gist of the various methods to characterize
aggregate mineralogy, summarizing the significance of [12] Richardson, I. G. (2008). “The calcium silicate hydrates”,
petrographic and geo-chemical investigations. Cement and Concrete Research, Vol 38, No. 2,
pp. 137-158.

9. ACKNOWLEDGMENTS [13] Neville, A. M. (2011). “Properties of concrete”, Pearson
Education Limited. Edinburgh Gate, Harlow England.
Authors are indebted to Dr R. Ramasamy, eminent geologist,
and former senior consultant to the department of civil [14] ASTM C125 (2007). “Standard terminology relating to
engineering, IIT Madras, for his valuable discussions and inputs concrete and concrete aggregates”, ASTM Standard, USA.
on mineralogy and petrography of aggregates. Further, we [15] Addis, B. J., and Owens, G. (2001). “Fulton’s concrete
gratefully acknowledge him for Figures 4 (k and l), and 5 (e, f, g technology”, 8 edition, Midrand: Cement and Concrete
th
and h). Institute, South Africa.

32 THE INDIAN CONCRETE JOURNAL | AUGUST 2022