Ground Modification: How Much Improvement?

Ground modification has been used on many construction sites to density granular material and reduce potential settlement or the susceptibility to liquefaction. This paper evaluates the benefits derived through several ground improvement methods, deep dynamic compaction, vibro-compaction, and vibro-replacement. These ground modification procedures were performed on several study sites with the effectiveness of the methods evaluated by comparing the tip resistance of pre- and post-construction cone penetrometer test (CPT) soundings. The results provided by the treatment methods were also evaluated with respect to the amount of fines observed in the subsurface profile. The results of our evaluation are intended to expand the availability of information on the effectiveness of these ground modification methods.