An experimental investigation on interference of piled rafts in soft soil

The interference effect on vertical load-deformation behavior of equally spaced rafts and piled rafts, placed in consolidated soft clay was investigated using small scale model tests. All foundations were assumed to carry an equal load, and settle to the same extent. The effect of spacing among foundations on the results is discussed in this paper. A new experimental setup is proposed in which uniform load can be applied. The bearing capacity decreased with decreasing spacing between the foundation. The interference effect becomes more prominent for piled raft foundations, where an increase in the foundations settlement was observed. The present experimental observations were compared to the results obtained by using PLAXIS. The present experimental data, however, indicates much greater effect of interference especially for smaller spacing among foundations. The results of this laboratory investigation will help in finding the minimum spacing between the rafts and piled raft foundation for better performance.