Expansion Index and Its Relationship with Other Index Properties

Abstract

Relationships between swell potential and soil index properties are commonly used in soil design. It was found that the Expansion Index as determined by the modified Arizona method, EIAZ, correlates very poorly to both Plasticity Index., PI, and percent passing US sieve number 200, P200, when considered separately. The product of these two parameters, however, wPI, improves the correlation from R2 values of 0.41 and 0.27, respectively, to 0.67.