It is well-known that soils may display strong nonlinear and inelastic characteristics. Furthermore, the viscosity or rheology of soft clays cannot be usually overlooked in the design of major structures founded on soft ground. Especially, rheologic deformation of soils may get considerable under high stress level. In fact, the saturated soft ground usually displays low strength, sensitive thixotropy, and high compressibility. In this paper, the soil deformation on interaction behaviour of piled rafts and soil foundation by using a fully coupled finite-element method of consolidation in which an elasto-viscoplastic model is incorporated. Through numerical computations, it is demonstrated that the coupled creep-consolidation analysis can give a more rational evaluation of overall performance of interaction of piled raft and soils and conventional analyses which overlooks time-dependency of soil deformation may give rise of inaccuracy in engineering evaluation and design of structures.