Abstract:
Abstract Design of a safe and economical foundation system is an important task
in tall build-ing design. Deep foundations such as piled foundations are generally
adopted to transfer heavy loads from superstructure to the bearing stratum. Providing
adequate geotechnical capacity and limiting the deferential settlement are two impor tant design considerations in the design of piled foundations. The foundation design
becomes economical when both the criteria of bearing capacity and settlement are
satisfied in an optimum way. A piled raft foundation is an advanced concept in which
the total load coming from the superstructure is partly shared by the raft through
bearing from soil and the remaining load is shared by piles through skin friction and
end bearing. Consequently, piled raft system is generally adopted when pile foun dations for tall buildings become uneconomical or unsatisfactory. Due to the three
dimensional nature of the load transfer, piled raft foundations are regarded as very
complex systems involving many interaction factors such as pile-to-raft, raft-to-soil,
and pile-to-soil. This paper intended to present a detailed discussion on the anal ysis of piled raft system addressing available analytical methods to analysis piled
raft system. Considering of deferent factors influencing the pile raft behaviour are
summarized in this paper. A detailed numerical analysis approach for the analysis of
piled raft foundation is discussed. Further, a case study investigating the performance
of piled raft system for an eighty-one storied tall building is presented.
