Improving Soil Density. Study Evaluates the Effectiveness of Three Ground-Improvement Methods

This article describes a study to determine the effectiveness of three ground-modification methods for densifying granular material and thus reducing the possibility of settlement or liquefaction. The three methods tested were: vibro-compaction, used when dealing with relatively clean cohesionless sands with silt contents less than 12-15% and clay contents less than 3%; vibro-replacement, generally used in marginal soils; and deep dynamic compaction (DDC), which is also used in relatively clean granular materials. The study compares the tip resistance of pre- and post-construction cone penetrometer test soundings at several study sites. The effectiveness of the individual procedures can be determined by comparing these resistance measurements and determining the improvement index. A previously developed improvement index was used, but the authors in the current study tried to account explicitly for the effects of fines content on the degree of improvement. Findings show that densification achieved through vibro-compaction and vibro-replacement is a function of the initial density and fines content of the material. As the fines content increases, the densification improvement generally decreases. Densification performance also appears to be affected by the type of fines. Findings show that the DDC process is not influenced by the fines content of the material to the same degree as the other 2 methods. These results indicate that the success of ground improvement technologies should be measured based on verification testing rather than an improvement index alone.

  • Availability:
  • Authors:
    • Mackiewicz, Scott
    • Camp III, William M
  • Publication Date: 2007-3

Language

  • English

Media Info

  • Media Type: Print
  • Features: Figures; Photos; Tables;
  • Pagination: pp 24-27
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 01045463
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Mar 29 2007 1:57PM