1. Part 3 SECONDARY CONSOLIDATION

2. Typical plot showing time rate of consolidation for an organic silty clay. Secondary consolidation occurs due to continual expunging of chemically-adsorbed pore water, at a reduced, but more-or-less constant rate under a more or less constant load (surcharge)

3. Secondary Consolidation The physical process believed to be responsible for secondary consolidation is sketched here; illustrating how planar clay platelets are slowly re-aligned perpendicular to the maximum principal stress, while expunging chemically-adsorbed moisture between the platelets

4. Raw secondary compression test data, as measured in a 14 week long test battery. Samples of this sandy silt were taken from a a deep urban fill in San Bruno, CA

5. Secondary Compression Index Relationship between natural water content and secondary compression index, from Mesri (1973) and NAVFAC DM-7.1-2 Note values for fibrous peats are the highest