Volume 21, Issue 3 (September 1998)
Consolidation and Permeability Behavior of High Porosity Baltic Seabed Sediments
The consolidation and permeability (hydraulic conductivity) characteristics of the high-porosity surficial seabed sediments from a test site in the Eckernförde Bay, Baltic Sea, were studied using a constant rate of strain (CRS) consolidation and hydraulic conductivity testing system employing flow pumps. These silty clay sediments are characterized by high void ratios, high organic content, and variable concentration of methane gas. Results from CRS consolidation tests show appreciable apparent overconsolidation of the sediments at the upper 200 cm with a gradual transition to normally consolidated states below 250 cm in depth. The highly compressible nature of the material is reflected in the large values of the compression index. The hydraulic conductivity of the box core samples ranges from 2.5 × 10−7 to 3.0 × 10−6 cm/s for void ratios ranging from 4.5 to 7.0 with a linear relationship between void ratio and log of hydraulic conductivity. The engineering behavior of these sediments is of practical significance in geoacoustic modeling of the seafloor for studies related to mine countermeasure programs.