Response of reinforced concrete piles including soil-pile interaction effects

This paper discusses the importance of modeling soilpile interaction in the response of reinforced concrete (RC) piles. A displacement-based, RC beamcolumn fiber model with distributed lateral deformable supports is presented first. The formulation is general and applies to both monotonic and cyclic loads. The proposed model is simple, computationally efficient and capable of representing the salient features of the soilpile interaction, including dragging force and gap formation along the pilesoil interfaces as well as hysteretic responses of piles and surrounding soils. Two applications are presented to illustrate the model characteristics, to show the model capabilities, and to discuss the importance of modeling the pilesoil system. The first application deals with a single end-bearing pile embedded in a cohesionless soil. The proposed beamcolumn model is used to investigate the effects of different model parameters on the pilesoil response, including pile length, pile diameter, and pile and soil nonlinearities. The second application validates the accuracy of the proposed model with the experimental results of a cyclic test on a RC pile/shaft system where the influence of the pilesoil interaction is essential. Results from the correlation studies indicate that the proposed model can represent well both global and local responses of the pilesoil system. The effects of the interfacial characteristics between pile and soil on the system response are also studied.