Parametric Study for Optimum Design of Combined Piled Raft Foundation (CPRF): Fid-Bau Portal

Parametric Study for Optimum Design of Combined Piled Raft Foundation (CPRF)

Suresh Babu, E. L. / Suneel Kumar, G. / Sasmal, Suvendu Kumar / Behera, Rabi Narayan

In most of the developed cities, skyscrapers have become a common sight. These high-rise buildings not only accommodate and cater to the needs of the masses, but also add to the overall aesthetics of the cities. Construction of these buildings is becoming popular due to the growing population density in cities all over the world. But these constructions result in an increasing weight of the structure, with soil bearing capacity being a constraint it compromises on the stability of the structure. In general, a raft foundation is used if the soil at shallow depths is adequate enough to bear the structural weight but if the soil strength is not adequate enough, there might be some excessive and/or differential settlements. To reduce these settlements in a raft, piles may be placed beneath the raft, and this is commonly called as combined piled raft foundation (CPRF). Thus, the CPRF may be provided as foundation in order to increase the bearing capacity of the foundation and also to reduce the differential settlement/s. In the present study, the usage of piles as settlement reducers in CPRF along with a parametric study is carried out. The various factors influencing the settlement behaviour of CPRF considered include raft thickness, length of the piles, arrangement of piles, and the diameter of piles. This analysis is carried out using a finite element method-based geotechnical analysis software package called PLAXIS 3D. It has been noticed that as the thickness of raft increased, the differential settlement and overall settlement got reduced. This study helps one to get a brief idea on different influencing parameters involved in the piled raft design.