Influence of pore water salinity on the compressibility of Maryland clay

Abstract

This experimental study investigates the compaction behavior of Maryland clay with different pore water salinity. Maryland clay powder was prepared with deionized water and CalCl2 solutions prepared at two concentrations (0.1 M/L Ca2+ and 1.0 M/L Ca2+) and then statically compacted in an oedometer cell. The compaction tests were complemented by microstructural characterization using mercury intrusion porosimetry. The effect of pore water salinity on the compaction behavior of the ML clay is quantified at both micro and macro scales. Results show that the compression index from 1D compression tests and the pore size distribution inferred by MIP are highly dependent on both the water content and pore water salinity. The compression index increases with water content but is not uniquely correlated with pore water salinity at a given water content. At low water contents, pore water salinity mainly affects the macro pores, while it leads to a significant influence on the micro pores when increasing water content.