Analysis of Load Sharing Response and Prediction of Interaction Behaviour in Piled Raft Foundation

Piled raft foundation is anticipated to show high load carrying capacity through partial load sharing between the pile and the raft components. But this complex load sharing behaviour due to the presence of interaction effects is not well known, and there is a scarcity of proper illustration and correlation among the interaction and load sharing factors. In the present study, prediction models are developed to estimate and correlate the load sharing factors and the interaction factors. 3D finite element modelling is performed for different foundation types in clayey soil underlain by sandy soil taking various design parameters. The nonlinear behaviour of the piled raft foundation, the load sharing factors and the interaction factors for every foundation types are evaluated, and a predicted model is suggested. The predicted expressions are also validated with the calculated results from the numerical analysis to a better goodness of fit. A proposed model is then suggested for the design of the piled raft foundation considering both the safety and serviceability conditions. The proposed simplified model provides an easy solution for the design of the piled raft foundation subjected to vertical loading.