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Quality variations in whin sill aggregates from Northumberland, England

  • Dearman W. R. 
  • Irfan Y. 
  • Money M. S. 
  • Turk N. 
  • Hussen T. I. 
International Symposium on Aggregates Theme 3. Tests on Aggregates

Summary

The Whin Sill is a dolerite intrusion with extensive outcrops in North East England. Quarries in the sill, provide the bulk of the crushed rock aggregates in the region suitable for roadstone. The dolerite is generally of high strength and little affected by weathering and thus yields high quality aggregates. At some quarries, however, dolerite of poor quality, locally known as “Woodhead”, is found. The “Woodhead” material differs from the normal dolerite is having a distinctive colour, lower strength and higher porosity. It can be shown that the material is produced by hydrothermal alterations related to calcite veining. Inclusion of Woodhead material in aggregates from one quarry lead to their rejection by a Local Authority and, as it proved impossible to separate the poorer material, the quarry closed.

Quality variations have been determined by a range of standard tests. Test results can be related to petrographic indices determined by quantitative thin-section analyses.

Keywords

Hydrothermal Alteration Point Load Strength Basic Igneous Rock Aggregate Crushing Value Aggregate Impact Value 

Variations de la qualite des granulats du sill de whin, Northumberland, Angleterre

Résumé

Le sill de Whin correspond à une intrusion doléritique, affleurant largement dans le Nord-Est de l'Angleterre. Les carrières dans ce sill fournissent la plupart des granulats pour les chaussées de la région. La dolérite, généralement peu altérée et de résistance élevée, donne des granulats de bonne qualité. Cependant, dans quelques carrières, une dolérite de mauvaise qualité est connue sous le nom local de “woodhead”; ce matériau diffère de la dolérite saine, par une couleur distincte, une plus faible résistance et une plus grande porosité. Il est montré que ce faciès est dû à une altération hydrothermale, en relation avec des filons de calcite. Une certaine proportion de “woodhead” dans les granulats a entraîné leur refus par les autorités locales et la fermeture de la carrière, car il était impossible de les séparer.

Les variations de qualité de ces matériaux ont été déterminées par des essais, dont les résultats sont corrélés avec des indices pétrographiques quantitatifs mesurés en lames minces.

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References

  1. ASHURST J. and DIMES F.G. (1977): Stone in Building, The Architectural Press Ltd. London, pp. 105.Google Scholar
  2. ASTM. (1980): Standard test method for soundness of aggregates by use of sodium sulphate or magnesium sulphate. Designation: ANSI/ASTM C88-76. Annual Book of ASTM Standards, Part 14, 48–53.Google Scholar
  3. BRITISH STANDARD 812. (1975): Methods for sampling and testing of mineral aggregates, sands and fillers. Part 1–4. British Standards Institution. London.Google Scholar
  4. BRITISH STANDARD 882 and 1201. (1973): Specification for aggregates from natural sources for concrete (including granolithic). British Standard Institution. London.Google Scholar
  5. DUNHAM A.C. and STRASSER-KING V.E.G. (1981): Petrology of the Great Whin Sill in the Throckley Borehole, Northumberland.Rep. Inst. Geol. Sci. No. 81/4, pp. 32. London, H.M.S.O.Google Scholar
  6. G.S.A. COLOR-CHART. (1970): Rock Color Chart. The Geological Society of America. Boulder, Calorado, U.S.A. pp. 16.Google Scholar
  7. HAMROL A. (1961): A quantitative classification of the weathering and weatherability of rocks. Proc. 5th Int. Conf. Soil Mech. and Found. Engng, Paris, 2, 771–774.Google Scholar
  8. HIGGINBOTOM I.E. (1976): Section 11.1. General requirements for rocks and aggregatesin Anon. 1976. Applied Geology for Engineers, H.M.S.O. pp. 378.Google Scholar
  9. HOLMES A. and HARWOOD H.F. (1928): The age and composition of the Whin Sill and the related dykes of the north of England.Mineral. Mag. 21, 493–542.Google Scholar
  10. HOSKING J.R. (1970): Road aggregates and their testing. One day Symposium on Quarrying, Bristol University.Google Scholar
  11. HOSKING J.R. and TUBEY L.W. (1969): Research on low-grade and unsound aggregates. Road Research Laboratory Report LR 293, pp. 30.Google Scholar
  12. IRFAN T.Y. and DEARMAN W.R. (1978): The engineering petrography of a weathered granite in Cornwall, England.Q. Jl. Engng Geol. 11, 233–244.CrossRefGoogle Scholar
  13. MENDES F.M., Aires-Barros L. and RODRIGUES F.P. (1966): The use of modal analysis in the mechanical characterization of rock. Proc. 1st Cong. Int. Soc. Rock Mech., Lisbon, 1, 217–223.Google Scholar
  14. WEINERT H.H. (1964): Basic igneous rocks in road foundations. S. African Council Sci. Ind. Res., Res. Dept. 218.Natl. Inst. Road Res., Bull., 5, pp. 47.Google Scholar

Copyright information

© International Association of Engineering Geology 1984

Authors and Affiliations

  • Dearman W. R. 
    • 1
  • Irfan Y. 
    • 2
  • Money M. S. 
    • 1
  • Turk N. 
    • 1
  • Hussen T. I. 
    • 1
  1. 1.Department of Geotechnical EngineeringUniversity of Newcastle upon TyneNewcastle upon TyneUK
  2. 2.Public Works DepartmentGeotechnical Control OfficeHong Kong

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