Piled raft systems are often suitable as foundations for large buildin
gs in soft soil, As the analysis of piled raft systems is very complex
, computers are often used. When a large group of piles or a large raf
t is involved, a large amount of computing time is required. This pape
r presents an approximation which reduces computer run time considerab
ly, and yet results in very little error. This approximate method shou
ld be useful for quick ol preliminary design. (C) 1997 Elsevier Scienc
e Ltd.