ABSTRACT
Stone columns are often used to improve soft soil ground, but a large settlement may be induced when the external load is large and strength of soft soil is low. In the study of the paper, piles are used together with stone columns to improve soft soil ground and to reduce foundation settlements. Physical model tests are conducted on soft soil ground improved with both stone columns and piles. It is found that soft soil ground reinforced with stone columns and piles has a higher bearing capacity and lower settlement than that improved using piles alone. A finite element analysis with Goodman interface elements gives a simulation, which is in good agreement with measured data. According to the research results, a design method for reducing settlement using both stone columns and piles based on the principle of settlement controlling is proposed. This method is developed for the piles working at a state of nearly ultimate bearing capacity so that pile-soil-foundation interaction can be taken into consideration.
