In order to reduce differential settlement and prevent heaving of surrounding ground due to fill loading, a new method using low strength pile with permeability has been devised. The pile material have been composed of hydraulic granulated slag and 12-20% cement of slag. After the design method having been presented on basis of model loading test result, soil improvement have been put to practical use with sand drain method. As a result, it have been confirmed that this method has been effective for reduction settlement, prevention heaving and same drainage as sand drain method
