ANALYSIS OF EMPIRICAL COMPRESSION INDEX EQUATIONS USING THE LIQUID LIMIT

Abstract

This paper proposes a new method to evaluate the reliability of published empirical formulas in terms of accuracy and applicability to different soil types. Different empirical models are proposed to properly approximate the compression index for a wide range of liquid limits and soil types. They were developed using a unique Soil Property Line (SPL) developed using a substantial number of published regression equations and compression data. Familiar empirical equations were examined for their reliability in predicting the compression index of clay for any liquid limit. A comparison was made between available and newly-proposed empirical formulas using combined regression data sets compiled independently by several authors. The newly proposed empirical compression index equations are applicable to wide ranges of clay soils, validating other published relationships. The degree of scatter and variations in the computed compression index values are minimized for any liquid limit.