Abstract Using production piles as test piles is the current trend of static loading test. It is very important how to determine the ultimate bearing capacity of piles with the results of production piles’ static loading test. The data from the reports of 60 driven cast-in-situ piles’ static loading tests in Nanjing are interpreted,and two mathematical models are adopted to study the static loading test results of production piles. The results indicate that the ultimate bearing capacity of single pile could quite precisely be determined from such test results with Van Der Veen’s models.