In the port of Antwerp is expanding the buffer capacity for a variety of liquids in storage tank facilities. By means of results of cone penetration test and settlement calculations (with log normal distribution) following EN 1997, for each zone were calculated a value of subgrade reaction. This value was verified with on site testing. With these values, a calculation model was made to determine the reinforcement. The possibility of Diamonds to calculation the total settlement was used to check the influence on the adjacent plate by modelling a flexible plate around the actual storage facility. The way of handling this project has guaranteed economic performance and currently in use, to everyone's satisfaction