Despite the developments in the theory and experimental methods in the last decades, floating sand/stone column subject is very scarce in the literature and there are still unclear and foregoing arguments about their reinforcing behaviour. To contribute to this subject the load-settlement behaviour of a model square footing reinforced with sand columns having variable lengths on a soft clay soil of finite thickness was investigated through a set-up in the laboratory conditions. Settlement improvements within and under the sand column area, variation of stress concentration ratio for different column lengths, the mean vertical stresses under the sand column area and the effects of length/diameter and area replacement ratios to the settlement response of the reinforced soil were investigated. It has been found that, the presence of floating sand columns reduce the settlements in the reinforced clay zone as well as in the zone underneath the sand columns. The amount of settlement reduction in the unreinforced zone underneath the floating columns was found significant.