Ground improvement is an important requirement in today's construction industry as landreclamation is becoming increasingly popular. The stone column technique is a very efficient method of improving the strength parameters of soil like bearing capacity and reducing consolidation settlement. Soil reinforcement can be an ideal solution for the improvement of clay. Out of other conventional methods, stone columns are effectively being used for ground improvement, particularly for the construction of flexible structures such as road embankments, oil storage tanks, etc on soft soils. It offers a much more economical and sustainable alternative to piling and deep foundation solutions. This report investigates thequalitative and quantitative improvement of individual load capacity of stone columns by varying the diameterof stone columns through laboratory model tests conducted on stone columns installed in clay beds prepared in controlled conditions in a large-scale testing tank. The results from the load tests indicated the performance of a smaller diameter stone column is superior to that of a bigger diameter stone column and the stone grit used to Promote the vertical drainage function of the column by acting as a good filter.