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Grain-size distribution of Italian raw materials for building clay products: a reappraisal of the Winkler diagram

Published online by Cambridge University Press:  09 July 2018

M. Dondi ,
B. Fabbri  and
G. Guarini
M. Dondi
Affiliation:
CNR-IRTEC, via Granarolo 64, 48018 Faenza, Italy
B. Fabbri
Affiliation:
CNR-IRTEC, via Granarolo 64, 48018 Faenza, Italy
G. Guarini
Affiliation:
CNR-IRTEC, via Granarolo 64, 48018 Faenza, Italy
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Abstract

The grain size of raw materials influences their behaviour during the technological process and affects many properties of building clay products. Over the last few years, brickworks have been technologically updated and grain size requirements have been modified to ensure good behaviour during shaping and drying. Therefore, the reference schemes used to assess the suitability of clays, such as the classic Winkler diagram, should be updated.

For this purpose, the grain-size distribution of 350 clays currently used in ~240 Italian plants was determined by X-ray monitoring of gravity sedimentation. Raw materials are basically represented by silty clays and clayey silts, while bodies present a narrower grain-size range. With reference to the Winkler diagram, most of the Italian bodies fall within the field of ‘thin-walled hollow bricks’, with no significant differentiation among the various product types.

In order to improve the grain-size characterization of bodies, a new classification scheme for Italian raw materials is proposed, based on three ranges: >10 µm, 2-10 µm and <2 µm, respectively. It allows distinction of specific grain-size features of bodies for (a) facing bricks; (b) roofing tiles; and (c) lightweight blocks, paving bricks and hollow slabs.

Type
Research Article
Information
Clay Minerals , Volume 33 , Issue 3 , September 1998 , pp. 435 - 442
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1998

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References

Decleer, J., Ottenburgs, R., Vanderberghe, N. & Viaene, W. (1981) Geological and physico-chemical characterization of Belgian non-refractory clay deposits and its implications for industrial use. Proc. lnt. Clay Conj'. Bologna-Pavia, 699-709.Google Scholar
Fabbri, B. & Dondi, M. (1995a) La produzione det taterizio in Italia, Faenza Editrice.Google Scholar
Fabbri, B. & Dondi, M. (1995b) Caratteristiche e diJetti del laterizio, Faenza Editrice.Google Scholar
Kolkmeier, H. (1991) Reliable test methods for the evaluation of brickmaking raw materials. Ziegelindustrie Int. 6, 282–290.Google Scholar
Konta, J. (1980) Properties of ceramic raw materials. Pp. 1 –32 in: Ceramic Monographs – Handbook of Ceramics. Verlag Schmid, Freiburg.Google Scholar
Schmidt-Reinholz, Ch. (1986) Typical raw materials for the manufacture of heavy-clay products. Interbrick, 2,6, 11–15.Google Scholar
Schmidt-Reinholz, Ch. (1993) Influence of preparation on certain quality characteristics of building ceramics. Tile Brick lnt. 9, 81–84.Google Scholar
Schmidt-Reinholz, Ch. & Schmidt, H. (1992) Important brick clays and their deposits in West Germany. Tile Brick lnt. 8, 235–241 and 349-352.Google Scholar
Shepard, F.P. (1954) Nomenclature based on sand-siltclay ratios. J. Sed. Pet. 24, 151–158.Google Scholar
van Wijck, J.H. & Heitink, G.H. (1993) The soft mud method of brickmaking – an overview of the essential aspects of the process. Ziegelindustrie Int. 3, 174-182Google Scholar
Winkler, H.G.F. (1954) Bedeutung der Korngrössenverteilung und des Mineral-bestandes von Tonen für die Herstellung grobkerarnischer Erzeugnisse. Ber. DKG, 31, 337–343.Google Scholar