Due to the volume compaction induced by creep effect of soft clay

the strength of soft clay increases over time

which leads to the growth of the bearing capacity of the driven pile installed in soft clay

even though the excess pore water pressure has been fully dissipated. Considering the installation of pile and the primary consolidation of the surrounding soil

the hyperbolic load transfer curves were employed in this study to model the load transfer characteristics of pile shaft and pile base

and the stress state of the soil around the pile was deduced by load transfer method. On this basis

taking advantage of an advanced elastic-viscoplastic model

the creep behavior of soil adjacent to the pile was evaluated by the quasi-overconsolidation ratio. Then

the evolution of soil strength during creep was analyzed

and a theoretical method was proposed for the long-term bearing capacity of driven pile in soft clay. The proposed theoretical method was verified by static load test. The variation of long-term bearing capacity of driven pile in soft clay with time was investigated

and the effect of soil parameters on long-term bearing capacity of driven pile was further analyzed. Results show that the long-term bearing capacity of driven pile in soft clay was primarily attributed to the increase of shear stress on lower pile shaft. The bearing capacity increased rapidly and then gradually slowed down with service time of pile. It was found that the evolution of long-term bearing capacity of driven pile was more significant in soil with higher creep index and swelling index. The theorical method presented in this study is expected to provide guidance and suggestion for determining and reusing driven piles whose superstructures have been demolished.