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Ezzat William

Ezzat William photo

BAppSc Geophysics, MAppSc Eng.Geol, MAppSc Eng.Sc., Dip. Maths and Teaching
Postgraduate Research Student
Centre for Geotechnical Research


Research project - Engineering performance of Bringelly shale

Supervisor: A/Prof David Airey
Associate Supervisor: Dr Tim Hull


Bringelly shale is a major geological unit in the Sydney Basin, Australia that is comprised predominantly of claystones with occasional sandstone layers. The shale and the residual soil derived from it have caused problems for structures founded on them. Although apparently a rock there is little evidence of cementation in the claystone. The material has been highly compacted and has very low porosity. To investigate the mechanical behaviour triaxial tests, direct shear box and ring shear test on reconstituted specimens have been performed and compared with the behaviour of natural specimens. The main aim is to investigate the normalised behaviour of the reconstituted material by reproducing compressed specimens at different stress level similar to that in the field. The behaviour of these specimens is to be examined within the context of the critical state concepts applicable at higher porosity. To investigate the effects of cementation, the behaviour of the reconstituted and natural material have been compared. It is found that the strengths of the natural and reconstituted samples at the same void ratio are similar, with both showing friction angles significantly less than the reconstituted material at higher void ratio.

Selected publications

  • William, E, and Airey, D.W. (1999a) A review of the Engineering Properties of the Wianamatta Group Shale. Proceedings of 8th Australian New Zealand Conference on Geomechanics, Hobart, 2, 641-646.
  • William, E. and Airey, D.W. (1999b) Influence of Swelling Strain on Selected Engineering Properties of Bringelly Shale at South West Region of Sydney, Australia. Electronic Journal of Geotechnical Engineering, Vol. 4.
  • William, E., Hull, T.S., and Airey, D.W. (2001) Behaviour of reconstituted soft rock, The 3rd International Conference on Soft Soil Engineering (3rd ICSSE), Hong Kong, No.3, pp. 607-611.
  • William, E., and Airey, D.W. (2001) Influence of stress level on the highly compacted shales in the Sydney basin, The 16th International Conference on Soil Mechanics and Geotechnical Engineering, Osaka, (to appear).
  • William, E., (2002) Mechanical Properties of Reconstituted Bringelly Shale". ISRM India Symposium on “Advancing Rock Mechanics Frontiers to Meet the Challenges of 21st Century", New Delhi.
  • William, E. (2002) Physical and mechanical characteristics of Bringelly shale, Electronic Journal of Geotechnical Engineering, vol.7B.
  • William, E. (2004) Understanding the Effects of Structure and Bonding in the Bringelly Shale. Geo Jordan 2004: Advances in Geotechnical Engineering with Emphasis on Dams, Highway materials, and soil Improvement, Alshibli, K., Malkawi, H., and Alsaleh,M. (eds). Irbid, No.1, pp. 277-285.
  • William, E. (2004) An evaluation of the role of fabric on stiffness and shear strength of Bringelly shale, Electronic Journal of Geotechnical Engineering, (reviewed).
  • William, E., Hull, T.S., and Airey, D.W. (2004) Influence pf pressure on the response of reconstituted Bringelly shale, Proc. 9th Australian New Zealand Conf. on Geomechanics, Farquhar, G., Kelsey, p., Marsh, J., and Fellow, D. (eds). Auckland, vol.2, pp. 724-730.
  • William, E. (2004) Understanding the effects of structure and bonding in the Bringelly shale, Electronic Journal of Geotechnical Engineering, Vol. 9A.
  • William, E. and Airey, D.W. (2004). Index properties and the engineering behaviour of Bringelly shale. The engineering geology of the Sydney region-revisited. AGS Sydney chapter mini-symposium, No.3, vol. 39, pp. 31-42.

Learning and Teaching

  • ENGG1803 Professional Engineering 1
  • CIVL2401 Soil Mechanics