Predicting Free Field Lateral Ground Movements due to Pile Driving in Soft Clay in Melbourne, Australia

It is widely known that driving piles and pile groups into soft saturated clay can lead to substantial ground movements. Such movements can have serious implications for brownfield sites where existing infrastructure, such as inground services or existing pile groups, may be located nearby. It is important to be able to confidently predict the associated ground movements due to pile driving in these situations so the proposed pile or pile group can be optimised, or controls implemented, to mitigate potential impacts on existing assets. This paper presents two methods of analysis, namely the Shallow Strain Path Method (SSPM) and Plaxis 3D, applied to compute free field lateral ground movements associated with driving large pile groups in soft clay at a site in Melbourne, Australia. A brief discussion is also provided on the response of a pile to the estimated ground movements. The methods of analysis are compared with site data and overall good agreement is observed between both methods of analysis and the site observed data.