In order to design machine foundations and to examine interaction between pile and soil, versatile horizontal dynamic loading tests were done to piles. In the tests both stiffness and damping values of piles were measured in overconsolidated clay and in earthfill sand. The stiffness of piles was analyzed by Winkler\u27s spring method and the damping of piles with Gazetas\u27 and Dobry\u27s method. The measured and calculated values were almost the same when stiffness was considered. In damping the measured values were about 40 ... 70% of the calculated values. Very important in the calculation is to know which is the gapping between pile and soil. In these tests the gapping was not measured
