One-Dimensional Creep Consolidation Model for Peat Soil

Peat soil exhibits significant creep deformation, and its consolidation law differs from that of soft soil. This study examines the strain characteristics of peat soils during three stages of consolidation using indoor one-dimensional creep consolidation tests. The results showed that the rebound deformation after the primary consolidation stage and the secondary consolidation stage is equivalent to the deformation seen during the primary consolidation stage, about 1.003 times. However, once the deformation stabilizes, the rebound deformation decreases to 0.32–0.85 times that of the deformation observed during the primary consolidation stage. The elastic and time-independent plastic strains of the peat soil showed two-stage linear changes with lnσz′. When the load was greater than the pre-consolidation pressure, the deformation modulus increases by approximately 2.10 and 1.56 times, respectively. On this basis, this study, for the first time, defines the creep rate according to the strain rate in the tertiary consolidation stage in the strain versus the time curve (εz~t). Based on the timeline, a one-dimensional creep consolidation model is established that can accurately predict the strain during the consolidation of the peat soil foundation. The results reveal distinct strain behaviors during each stage and improve the theoretical basis for the study of creep.