Changes in the course of constant loading consolidation in soil with modeled granulometric composition contaminated with petroleum substances

The effect of contamination with petroleum substances (A1 jet fuel and 15W40 mineral oil) on the compressibility and consolidation of mixtures of ice-dammed clay and aeolian sand was determined in a Barden–Rowe consolidometer adapted for liquid-phase contamination tests. The deterioration of the filtration capacity of the contaminated soil medium relative to the non-contamination condition is reflected by the mobilization of higher values of pore pressure u b and pore water pressure parameter C CL in the course of consolidometer tests. As a consequence, lower values of the compressibility modulus M 0 and the consolidation coefficient c v are obtained in relation to the results of uncontaminated samples. This generally indicates changes in the consolidation parameters of the soil medium in the presence of the tested contaminants. Methodologically, a delay in the onset of the steady-state phase of constant loading (CL) consolidation was observed in contaminated soils. This provides a rationale for programming the tests at lower values of the CL rate. At the same time, the unified model characterization of C CL–T CL allows us to assess the reliable nature of the results. This allows one to recommend CRL (constant rate of loading) tests as a reliable tool for determining the consolidation properties of cohesive soils in the design of soil isolation barriers.