Abstract: This paper presents briefly the application of dynamic pile testing to bearing capacity determination of a pile embedded in loose to compact sand and silt layers. The possibility of liquefaction of the loose layers as a result of cyclic loads such as earthquake, and therefore, reduction in shaft resistance of the pile are investigated. The Pile Driving Analyzer (PDA) was used for dynamic testing of the pile during driving by the hammer. The data was then further evaluated by the rigorous numerical analysis program CAPWAP to determine the static bearing capacity, and to distinguish between the toe resistance and the distribution of the shaft resistance along the pile. The results at the end of driving and also after a 30-minute wait indicated that the shaft resistance had gained an additional strength of 42% as a result of soil set up.