Design of dynamic footings in The Pilbara Region of Western Australia

Simon Hope


With the continuation of Western Australia’s resources boom, the construction of specialised mining infrastructure in remote locations provides interesting and unique challenges to geotechnical engineers. Large ore-processing structures, such as screening plants and crushing facilities, are designed to vibrate as part of their routine operations. This forces the footing to withstand dynamic loading that can potentially result in large differential settlements or bearing capacity failures if not founded on suitable material or designed appropriately.

To assist the structural and mechanical design of these dynamically loaded structures, a dynamic shear modulus value is required for the soil-structure interaction. The unique geological and geotechnical conditions of the Pilbara region present specific challenges and yet there is limited published information available regarding methods of assessing the dynamic shear modulus for these conditions.

This paper presents a summary of relevant published information, investigation methods and a weighted average method of assessment to estimate the dynamic shear modulus for typical Pilbara ground conditions.