Method for Estimating the Degree of Improvement in Soil between Adjacent Tamping Locations under Dynamic Compaction

Real dynamic compaction (DC) sites are composed of a series of tamping locations. However, previous studies mainly focused on single-location tamping and paid little attention to the influence of adjacent tamping locations. This paper proposes a method for estimating the degree of final soil improvement with depth in the compacted area between adjacent tamping locations. Extensive numerical parametric studies were conducted to investigate the influence of each parameter on the degree of soil improvement. Based on the results obtained, dimensionless correlations between the relative density increment ratio at certain depths and combinations of soil and construction parameters were performed with the dimensional analysis method. Then, the dimensionless correlations, together with the crater depth and depth of improvement, were used to determinate a prediction curve to describe the variation in the degree of improvement with depth along the midline between adjacent tamping locations. The reliability of the proposed formula was examined by comparing its predictions with the measured results. Finally, the applicability of the proposed formula for the determination of construction parameters was illustrated using the Changi DC treatment project.