This paper presents a numerical investigation of kinematic soil-inclusion interaction in rigid inclusion (RI) reinforced soft ground. A 3D nonlinear finite element model was built, employing advanced hypoplastic constitutive laws for clay and sand. The numerical model was calibrated and validated against dynamic centrifuge tests performed at Gustave Eiffel University -Campus Nantes, France. Parametric studies were then conducted to examine the effects of ground motion characteristics, inclusion stiffness, and tip conditions (end-bearing vs. floating) on surface response and bending moments along the rigid inclusions. The results indicate that end-bearing inclusions significantly amplify ground motion in the reinforced zone, particularly at high frequencies, and mobilize large bending moments near the interface with the stiff layer. In contrast, floating inclusions attenuate spectral accelerations, especially at low periods, and reduce bending demands while shifting the location of the maximum bending moment upward along the shaft. Increasing RI stiffness amplifies surface response and bending moments under end-bearing conditions, whereas floating inclusions show limited sensitivity to stiffness variations. Overall, the study highlights the importance of considering both kinematic interaction and tip conditions in the seismic design of RI-reinforced foundations, and the floating inclusions could offer potential benefits in reducing the seismic demand.