Estimation of the compaction characteristics of soils using the static compaction method

Abstract

Ground improvement using mechanical stabilization is commonly applied by performing thestandard Proctor compaction test, which requires a significant quantity of soil, usually obtainedfrom open pits. A static compaction test is an alternative laboratory compaction test. Althoughresearchers have shown that the results of miniature size static compaction tests are comparablewith that of standard Proctor tests in terms of the maximum dry density and the optimum watercontent, no attempt has been made to compare the two fundamental properties of the compactedsoil: undrained shear strength and hydraulic conductivity. The scope of this investigation was toestimate the level of static compaction energy required to (1) obtain a compaction curve similarto that of the standard Proctor test; (2) reconstruct compacted soils using the standard Proctor andstatic compaction tests at the optimum water content; and (3) compare the undrained shear strengthand hydraulic conductivity of compacted soils. The compacted soils at the predetermined energylevel were subjected to hydraulic conductivity tests using the rigid-wall falling-head permeabilitymethod. Undrained shear strength tests were performed by employing a high-capacity laboratoryvane shear apparatus on compacted samples of both the standard Proctor and static compactiontests. The present investigation revealed that the static compaction test, requiring about only 10% ofthe soil necessary to perform the standard Proctor method, provides comparable results in regard tohydraulic conductivity and undrained shear strength.