Behavioral study of piled raft foundation on cohesionless soil for eccentricity

The performance of piled raft foundation on sand is analyzed with reference to its bearing capacity and settlement. This paper presents an experimental study of the effectiveness of using piles on the behavior of an eccentrically loaded raft. The parameters that varied are the piles arrangements, piles length and load eccentricity. The improvement in the bearing capacity is represented by a non dimensional parameter called the load improvement ratio (LIR). The results of the tests show that the inclusion of piles at an eccentricity reduces the bearing capacity and also it decreases significantly as the eccentricity also increases leads to a reduction in raft settlement and tilts. However, the efficiency of the piled raft system depends on the load eccentricity ratio and pile arrangement. Based on the test results, the influence of different parameters is presented and discussed. However, the efficiency of the piled raft system depends on the load eccentricity ratio and pile arrangement. Raft foundations are often subjected to eccentric inclined loading because of the influence of lateral loads cause as a result of high wind and seismic actions and that may result in tilt of the structures particularly in case of high rise buildings. Using the settlement reducing piles beneath the raft in such cases may increase the soundness of the structure and may reduce the tilt of the raft. However, the piled raft subjected to eccentric and inclined loads has not been fully studied. Most of the research work was done on parametric numerical study for uniformly distributed load or concentrated column loads on piled raft. So that the study is necessary to gain more understanding of behavior of piled raft foundation for eccentric inclined load over cohesive soil/layered cohesive soil mass that creates overturning of the structure, which is commonly found in practice.