Effect of soil-foundation interaction on the reinforced concrete multi-storey buildings

Soil-foundation interaction plays an important role in the design of reinforced concrete multi-storey buildings and in the behavior of structures laid on a soil medium. This study investigates the effects of soil-foundation interaction on the reinforced concrete multi-storey buildings of different heights (2, 4, and 6 storey) and supported by three different types of foundations including raft, strip, and isolated foundations. The selected case studies have been analyzed using finite element method implemented by PLAXIS 3D software based on the Mohr-Coulomb soil model. The effect of soil–foundation interaction on the maximum settlement and the internal forces developed in structural elements including axial force, bending moment, and shear force is evaluated. It is found that the maximum settlement reached 118.4 mm in the 6-storey raft foundation case while, the axial force in columns, bending moment in beams, and shear force in beams have varied up to 37.11%, 107%, 57.2%, respectively by considering soil-foundation interaction compared to those in buildings with fixed ends at base.