This research investigates an innovative approach to improve the shaft bearing capacity of cast-in-place pile foundations by utilizing passive inclusions (Hooks) that will be mobilized if movement occurs in pile system. An extensive experimental program was developed to study the shaft bearing capacity of cast-in-place piles with and without hook system in soft clay and sand. First phase of the experiment was developed to investigate the effect of passive inclusion on pile-soil interface shear strength behaviour, employing a modified direct shear test apparatus. The interface strength obtained for pile-soil specimens was found to significantly increase when passive inclusions were implemented. Residual friction angle for concrete-sand interface increased from 22 degrees to 29.5 degrees when two hook elements were used at the pile-soil interface. The pile-clay adhesion was also increased from 19 kPa to 34 kPa.