Secondary Settlement
To describe a gradual creep of soil during secondary settlement the program employs the Buissman method (it incorporates the index of secondary compression Cα derived by Ladd). From observations suggesting that the soil deformation follows a linear path when plotted in semi-logarithmic scale against time Buissman proposed the variation of ε due to long-term stress in the form:
where: | ε | - | total deformation |
εp | - | deformation associated with primary consolidation | |
εs | - | deformation associated with secondary consolidation | |
t | - | time of consolidation | |
t0 | - | reference time |
Time dependent variation of strain (primary and secondary consolidation)