Load sharing ratio of raft in piled footing on granular soil by model test

This study was undertaken in order to investigate the behavior characteristics of a piled footing through the laboratory model tests, the numerical and analytical analyses. The model tests were conducted about a piled footing, the free-standing pile group, a single pile, as well as a shallow footing under equal conditions. The pile spacing and length, group type and soil conditions were varied in the laboratory model tests. The experimental results were compared with those by the commercial program, DEFPIG, conventional method and Phung's method. As the results of this study, it was found that the behaviors of a piled footing were affected by pile spacing, length and soil conditions. Phung's method proved to be reliable for estimating the experimental results. The raft of a piled footing carried out a considerable portion of external load. The load sharing ratio (LSR) depended on the pile spacing, length, relative density and settlement level. The LSRs by Phung's method agreed well with those by model test, but DEFIG overestimates those.