Semi-analytical solution for negative skin friction development on deep foundations in coastal reclamation areas

•A semi-analytical approach capable of modelling the whole consolidation process of backfilled soil before and after pile driving is proposed.•The one-dimensional and two-dimensional consolidation theories are successively adopted and coupled in the time domain.•The time-dependent development of excess pore water pressure, skin friction, and axial force is revealed.•Optimal piling time is proposed to shorten the construction period and relief negative skin friction.