Read Journal 0077 Volume 59 No 2 – Effect of the minimum void ratio on the vertical intercept of the steady state line of non-plastic soils

The steady state line (SSL) plays a key role in understanding and modelling the mechanical response of soils. Accordingly, understanding how the SSL correlates to soil index properties is of primary importance. A previous study reported that the vertical location of the SSL (Γ1) in void ratio (e) versus mean effective stress (p’) space is correlated to the minimum void ratio (emin). However, the correlation only included soils with narrow particle size distributions (PSD) and low
fines content (FC). In the current study, published data corresponding to 30 non-plastic soils were re-processed to further explore the applicability of the Γ1–emin correlation. The results indicate that the Γ1–emin correlation is linear (R2 = 0.85) and valid regardless of the coefficient of uniformity (Cu), FC, and particle shape. The Γ1–emin dataset presented herein was also compared to a previously published dataset, and good agreement was observed. It is proposed that the Γ1–emin correlation can be very useful to understand how the Γ1 of different non-plastic soils compare to one another, and to minimise the extent of triaxial testing required when characterising a soil deposit from an SSL standpoint. Limitations of the Γ1–emin correlation are also discussed.