Due to the complex nature of the piled raft foundation, its realistic design relies on the more rigorous computer based methods using either finite element or finite difference based soft wares. This study develops a numerical method that incorporates the different interactions which are the main causes of the complexity of piled raft foundation using a finite difference based software F LAC3D. Both unpiled raft and piled raft foundations were modeled using F LAC3D. The dimension of raft, pile spacing ,diametere and length of piles, stiffness of underlain soil were used as parameters. The study includes the study of piled rafts subjected to lateral loads. The raft thickness is set so that the raft flexibility is to be in the range of 0.1 to 5 in order to make the raft experiences both bending moment and settlements. The study presents the load settlement relationship and the bending moment result of the raft and the piles, which were run in large strain analysis. For the purpose of checking weather the model developed was in appropriate accuracy, two validating materials were used for the vertical loading case. One is an experimentally studied research (used as a verification material) and the second is a study conducted using different methods of piled raft analysis. The result of both validation materials show that the model is in good accuracy. Moreover, a centrifuge model was used to validate the piled raft subjected to lateral load. The interfaces between the soil and the structural elements(the raft and piles) were appropriately modeled by providing the interface deformation and strength properties. The deformation properties refers the normal and shear directed stiffness and the strength properties are the cohesion and angle of friction. The structural elements (piles and rafts) are assumed to act in the linear elastic range and hence, elastic isotropic constitutive model is used. However, Mohr-Coulomb elasticperfectly plastic model is used for soil materials. The p-multipliers of piled rafts for pile spacing of 3D and 5D were computed. The pile spacing were in both directions and it has been observed that the pile spacing in the direction transvese to the loading direction has not effect on the pile pile interactions in the case of lateral load. Application of vertical load to piled rafts subjected to lateral load decreases the lateral displacement of piles.