Aspects of Compaction Grouting of Liquefiable Soil

Abstract

The purpose of this paper is to review available case-history data on the treatment of liquefiable soils by compaction grouting, and to provide observations that are useful in evaluating the effectiveness of future compaction-grouting applications. Observations are made on practical aspects such as the effect of construction procedures on treatment effectiveness, the types of soil effectively treated, and issues in in-situ testing for quality control. An approximate relationship is established between the mean grout take and treatment effectiveness, which illustrates that grout takes have been consistently greater than would be anticipated based on common design calculations. This apparent discrepancy is attributed to a concentration of volumetric strains near the grout mass while in-situ penetration tests are commonly performed at treatment grid centers (farthest point from grout mass). Quantifying the composite behavior of a compaction-grouted soil mass will require an improved understanding of the treatment mechanisms.