Ground energy and impact of rolling dynamic compaction - results from research test site

As a major component of research activities at Sydney and Adelaide Universities into various aspects of rolling dynamic compaction as performed with the “square” impact roller, an experimental test site has been established. The test site is approximately 100m by 50m, and is part of a larger industrial property in Wingfield, South Australia. Geologically, the site comprises approximately 1-2m of non-engineered fill, overlying Estuarine deposits. The primary objectives of the work at the test site relate to quantifying the effects of the impact roller in terms of energy delivered to the ground and the ground response. Impact rollers with solid 4-sided modules of mass 8t and 12t are utilised. A monitoring and testing regime has been developed that includes physical measurements of energy on and below the impact module, surface settlement and sub-surface layer compression measurements. Early results from the testing programme provide a basis for understanding and developing the relationship of delivered to transmitted energy for the particular impact modules used at this site, the dissipation of energy through the ground and the effects on the various strata at depth due to module mass and number of passes (or energy input). The output from this study will form the basis for modelling ground conditions at this site and the effects of the impact rolling. The data thus generated will support further studies into numerical modelling of rolling dynamic compaction and the on-going programme of testing at other sites with different geological characteristics.D.L. Avalle, B.T. Scott, M.B. Jaks