Polish experience of dynamic tests for bored piles

In the paper some examples of dynamic load tests (DLT) of bearing capacity of piles installed in Poland are presented. The testing method shown allows a good estimation of bearing capacity of piles and can be treated as equivalent to static tests. The comparison of load-settlement curves from dynamic tests with corresponding static load test curves reveals good agreement of the results obtained. However, some practical examples presented show the differences in ultimate resistances received by two methods analysed. Final stages of load-settlement curves and their relation to static curves still need additional testing and analyses. The basic advantage of the dynamic method for the assessment of pile's bearing capacity is an elimination of anchoring equipment as well as relatively short time of test duration which becomes of particular importance in difficult site and technical conditions, especially for carrying out static pile load tests (SPLT). Dynamic load tests should be calibrated by static load tests treated as reference tests for a given foundation area analyzed. According to Eurocode 7, larger numbers of DLT tests will enable in the future an introduction to the engineering practice respective safety coefficients, together with better use of the piling constructions at safety preserved.