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A lot of study has shown that the distribution of vertical stress in soil just below a loaded tyre is not uniform, and the stress distribution as well as the size and form of the tyre-soil interface are decisive for the topsoil compaction. The distribution of vertical stress was measured in the contact area for three different tyre inflation pressures (85, 100, 120kPa) and load of 21kN. The study took place on a sandy soil in Zhuozhou city, Hebei province. The effects of three different inflation pressures were tested in a randomized block design with three replicates. The vertical stress was measured with load cells located in about 0.1m soil depth. The collected data in the experiment was used to calibrate and validate the FRIDA model. The validated FRIDA was used to predict soil-tyre contact area and the stress distribution across soil-tyre interface. The validation results showed that the RMSE(root mean square errors) and Bias (standard deviation) for soil-tyre contact area were ranged from 0.022m2 to 0.013m2 and from -0.19m2 to 0.019m2, respectively. The decision coefficient of contactarea between the tested and simulated values was 0.948. The relative errors (RE) of measured and predicted values of peak stress and mean stress were generally less than 0.1. Results showed that the FRIDA model could predict the soil compaction problems in sandy soil of north China. The FRIDA model was used to simulate the soil-tyre contact properties and stress distribution at different tyre inflation pressures. At the recommended inflation pressure, tyre displayed a stress distribution across the width of the wheel that could be evaluated as optimal with regard to a minimized topsoil compaction. The FRIDA model seems very well suited for describing the stress distribution at soil-tyre interface, but should be validated with other soil conditions.