Engineers Australia

Ground vibrations from dynamic replacement column installation

Greg Hackney

Abstract

Dynamic Replacement is a ground treatment technique that involves forcing rock into a soft soil substrate using a free falling mass to improve ground conditions. The large amounts of energy involved in Dynamic Replacement result in significant ground vibrations which can result in damage to nearby infrastructure if not managed properly. Presented are monitored ground vibration records for Dynamic Replacement columns at a site in Brisbane, Queensland, and assessment of the records to provide a basis for making initial predictions on potential vibration magnitudes. Discussion on the management protocols adopted as part of the works to mitigate the risk of damage to buried electricity infrastructure is also provided.