Case Studies For Piled Rafts On Clay

Piled rafts have proved to be an effective way of improving the overall performance of a foundation. In the case of structures built on clay, a raft foundation alone may result in excessive settlement. A piled raft foundation is a solution in which the piles provide localised support in heavily loaded regions or areas where deflection is excessive and results in reducing the overall and differential settlements as well as tilting of the foundation. Case histories for piled-rafts foundation on clay will be presented in this paper. The foundations have been studied using a finite layer method for the analysis of a horizontal layered soil and a finite element method for the analysis of the raft and piles. The analysis takes into account the complex soil-structure interactions which govern the behaviour of the piled raft. Case studies of piled rafts on clay will be examined and the results will be compared with the in situ measurements and other numerical results. Comparisons are made in terms of load distribution among piles and the overall and differential settlements.