clay deposit; characterization; building material; Cameroon
Abstract :
[en] Clayey deposits of Nanga-Eboko (Central Cameroon) were studied to assess their potential as building materials. Characterization was performed using XRD, IR, XRF, DTA/DTG and firing. Clays appear as discontinuous pockets with the same organizational characteristics in three villages located on both sides of the Sanaga River. The average thickness of exploitable layer is about 3m. The estimated tonnage ~7-17x105 m3 can supply an industry of great importance. SiO2 (~70%), Al2O3 (~15%) and Fe2O3 (~4%) are the predominant oxides of the natural clays. Quartz (~55%), kaolinite (~33%), illite (~5%) and K-feldspar (~4%) are major minerals. Clays are not suitable for building construction due to their fine-grained size and high plasticity properties. Firing properties of bricks (950 and 1050°C) are good despite the high shrinkage values. Therefore the addition of "degreasers' is recommended to control shaping and drying.
ASTM-America Society for Testing Materials, Standard Test Method for Particle-Size Analysis of Soils. ASTM D-422-63, 1998.
ASTM (1972) American Society for Testing and Materials, Water absorption, bulk density, apparent porosity, and apparent specific gravity of fired whiteware products, C 373-72.
ASTM (1977) American Society for Testing and Materials, Flexural properties of ceramic whiteware materials, C 674-77.
ASTM (2000) America Society for Testing Materials Standard Test Method for Liquid Limit, Plastic Limit, and Plasticity Index of Soils. ASTM D-4318.
Bain J.A. & Highley D.E. (1979) Regional appraisal of clay resources. A challenge to the clay mineralogist. Pp. 437-458 in: Proceedings of the IV International Clay Conference (M.M. Mortland & V.C. Farmer, editors). AIPEA, Oxford, 10-14 July 1978.
Biscaye P.E. (1965) Mineralogy and sedimentation of recent deep-sea clay in the Atlantic Ocean and adjacent seas and oceans. Geological Society of America Bulletin. 76, 803-832.
Boski T., Pessoa J., Pedro P., Thorez J., Dias J.M.A. & Hall I.R. (1998) Factors governing abundance of hydrolysable amino acids in the sediments from the N.W. European Continental Margin (47-50°N). Progress in Oceanography, 42, 145-164.
Celik H. (2010) Technological characterization and industrial application of two Turkish clays for the ceramic industry. Applied Clay Science, 50, 245-254.
Christidis G.E. (2011) Advances in the Characterization of Industrial Clays. EMU Notes in Mineralogy, 9, European Mineralogical Union, Mineralogical Society of Great Britain and Ireland. 341 pp.
Cook H.E, Johnson P.D., Matti J.C. & Zemmels I. (1975) Methods of sample preparation and X-ray diffraction in X-ray mineralogy laboratory. Deep Sea Drilling Project, University of California, Riverside. Contribution no.74-5, 999-1007.
Dondi M., Fabbri B. & Guarini G. (1998) Grain-size distribution of Italian raw materials for building clay products: a reappraisal of the Winkler diagram. Clay Minerals, 33, 435-442.
Kloprogge J.T., Ruan H.D. & Frost R (2002) Thermal decomposition of bauxite minerals: infrared emission spectroscopy of gibbsite, boehmite and diaspore. Journal of Materials Science, 37, 1121-1129.
Konta J. & Künher R.A. (1997) Integrated exploration of clay deposits: Some changes of strategy. Applied Clay Science, 11, 273-283.
Manning D.A.C. (1995) Introduction to Industrial Minerals. Chapman & Hall, London. 275 pp.
Ministère du Développement urbain et de l'Habitat (MINDUH) (2007) Rapport annuel d'activités. 105 pp.
Moore D.M. & Reynolds R.C. Jr (1989) X-Ray Diffraction and the Identification and Analysis of Clay Minerals. Oxford University Press, Oxford, 332 pp.
Nzenti J.P., Barbey P., Macaudière J. & Soba D. (1988) Origin and evolution of late Precambrian high-grade Yaounde gneisses (Cameroon). Precambrian Research, 38, 91-109.
Oliveira A., Rocha F., Rodrigues A., Jouanneau J., Dias A., Weber, O. & Gomes C. (2002) Clays minerals from the sedimentary cover from Northwest Iberian shelf. Progress in Oceanography, 52, 233-247.
Reeves G.M., Sims I. & Cripps J.C. (2006) Clay Materials used in Construction. Geological Society of London, 525 pp.
Sakizci M., Erdogan B.A. & Yörükogullari, E. (2009) Thermal behavior and immersion heats of selected clays from Turkey. Journal Thermal Analytical and Calorimetry, 98, 429-436.
Sigg J. (1991) Les produits de terre cuites. SEPTIMA, Paris, 423 pp.
Thibault P.M. & Le Berre P. (1985) Les argiles pour brique. BRGM. 1985. CRMO 65; MIMEE, Yaoundé, Cameroun.
Vidinha J., Rocha F., Andrade C., Gomes C. & Freitas C. (2007) Clay minerals-a mineralogical tool to distinguish beach from dune sediments. Journal of Coastal Research, SI 50 ICS-2007 (Proceedings), Australia, ISSN 0749.0208, 216-220.
