Studies on groups of stone columns in soft clays

In weak soft clayey deposits extending over a large depths, there are some difficulties in choosing a proper type of foundation even for lightly loaded structures. In this paper, results obtained from single and groups of model stone columns installed in soft clays under controlled conditions are presented and discussed. After showing the influence of placement moisture content of the surrounding soil and length to diameter ratio of the column from the results obtained from tests on single column setups, this investigation is extended to groups of columns. These results showed that the stone columns can be satisfactorily used to increase the support capacity of the soft formation by 2 to 3 times.