Construction of buildings, highways, and railway embankments over soft clay soils is a challenging task as even a small applied pressure may lead to large settlements, bearing capacity failure, large lateral movement, slope instability, etc. These issues are addressed by increasing the shear strength of the clay by means of pre-consolidation using Prefabricated Vertical Drains (PVDs). Generally, PVDs are installed in soft clay soils with the help of a mandrel. The installation of mandrel causes severe disturbance of the soil surrounding the drain resulting in a smear zone. The presence of the smear zone inhibits the consolidation process. In this study, the effect of smear zone on the consolidation behaviour of soil is studied using reconstituted soil in a large-scale consolidation apparatus with a prefabricated vertical drain. Two test conditions, viz. without smear and with smear were simulated. Variation of pore pressure and settlement with time were monitored throughout the test. The size of the smear zone was identified based on the change in values of permeability determined by testing the samples cored at different locations in vertical and radial directions from the pvd. The smear zone extent was found to be 3.5 times the equivalent mandrel radius and its permeability is around 1.4 times less than that of the undisturbed soil. In addition, these experimental cases were also simulated using 3-dimensional numerical models. The two parameters of interest are smear zone permeability and the extent of the smear zone. From the parametric studies, it was found that the smear zone permeability has a significant effect on the consolidation rate than the extent of the smear zone. Lastly, the 3D numerical model is developed and validated against the field data collected from JNPT port, Mumbai. The experimental set up, the results obtained from laboratory tests and the validation of the numerical models based on field data will be discussed in the seminar.