STUDY OF PILED RAFT FOUNDATION ON SOFT GROUND FOR MID RISE BUILDING

Abstract

ABSTRACT Piled Raft Foundation on Soft ground is an very Suitable foundation System where the bearing capacity of the raft is taken into under consideration in supporting the loads from the superstructure. Piled rafts can be an economical alternatives to conventional pile foundation in circumstances where the raft foundation is capable of providing significant load capacity but, on its own may settle excessively. High rise Building often rest on pile foundation, which are designed using the conventional methods, where the piles take the full load from the superstructure. Recently it is increasingly recognized that the use of piles to reduce the foundation settlement and differential settlement can lead to considerable savings. Only a limited numbers of pile, Called Settlement Reducers, may improve the ultimate load capacity, the settlement performance, as well as the required thickness of the raft. The Application of FEM method which is used in SAFE software in design of piled raft foundation is also discussed. In this Report the behaviour of pile raft foundation supported by piles ( un - identical ) is examined by the use of the Software program SAFE ( only personalized use ) and ETABS ( commercial ) based on FEM. The effect of pile length, diameter and spacing of piles on reducing overall settlement was determined and an analysis and design was undertaken. Attention has been also focused on the improvement of the foundation performance due to the raft provide a reasonable measure of stiffness and load resistance. The friction piles in a piled raft system are located strategically to enhance the bearing capacity of the raft and also to control the settlement. therefore, piled raft is technically competent foundation system and offer significant savings in terms of overall foundation cost as compared to conventional piled foundation. This s because the conventional piled foundation usually ignore the contribution of raft and assumes the loads are supported entirely by the piles. However, the use of piled raft foundation requires careful design and analysis. In this report, design issues on piled raft foundation system will be discussed with particular references to the building on soft ground. The Piled raft system has been successfully design and constructed on soft ground