Analysis and Design of Piled Raft Foundation Taking into Account Interaction Factors

In a combined piled raft foundation (CPRF) both and piles take their share of the total load applied. However, in practice, contribution taking is usually ignored assumed to be supported on piles. This way CPRF becomes excessively conservative uneconomical. To economize design, relative sharing has found. this connection, different simplified methods have been developed, each one with some limitations. study, three applied two cases pile-raft systems. The include Randolph, Poulos-Davis-Randolph, modified Poulos-Davis-Randolph. first case hypothetical consisting 12 m × square group nine second study an actual eight-story building constructed Peshawar, Pakistan. system, resting very soft clay underlain by dense sand. studies are also modelled finite element program PLAXIS 3D for comparison. results all comparable 3D. Randolph method much closer studied. Furthermore, it shown that system can used as “stress reducers” well “settlement reducers.” Additionally, effect interaction factors evaluated s/d ratio varying soil stiffness. It was concluded ignoring these leads unsafe design system.