Engineers Australia

Foundation properties of variably weathered rock beneath a heavy mineral processing plant

David Starr

This presentation covers an assessment of rock mass properties in a large foundation for a new Ball Mill at McArthur River Mine, Northern Territory, Australia. The results of geotechnical mapping in a substantial foundation excavation in a sequence of variably weathered meta-sediments are described. Deformation modulus values are evaluated using estimated UCS values and fracture frequency ratings, based on tables of modulus values and relationships developed by several authors. Lower bound modulus values are discussed in the context of the results of plate load tests undertaken by others in the foundation excavations. Total and differential settlements expected under the design loading are considered to be within the allowable tolerances. The results obtained using a simple settlement monitoring system support this conclusion.

Speaker biography

David Starr is a Principal Geotechnical of Golder Associates in Brisbane. He has over 40 years’ experience in a range of civil projects in the UK, Europe, Australia, New Guinea, Fiji, Indonesia, the Middle East, Hong Kong, West Africa, and USA, including geotechnical investigation, design, and construction monitoring. He has been based in Brisbane for 30 years. David Starr’s experience in geotechnical engineering, includes a number of infrastructure projects entailing rock characterization and rock excavation, covering geological and geotechnical investigations, rock property characterisation, rock excavation and support design, foundation and construction performance assessment, contract claims assessment and as an expert witness on over twenty cases.

David Starr has published 20 technical papers covering topics such as case histories of infrastructure projects, and on professional practice and legal issues. David is the Australian representative on ISSMGE committee TC40 Forensic Engineering, and JTC4, Professional Practice. In 2006, David was awarded Queensland Professional Engineer of the Year by Engineers Australia.

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