Abstract: In Harbor Engineering, it is often the case that subsoil consists of layered soils. In China, Hansen 61’s methods、Hansen 69’s methods and developed Sokolovski methods were recommended by the code to estimate the ultimate bearing capacity of layered foundation. However, in practice the ultimate bearing capacities of layered foundations predicted by the three methods are different from each other. Considering inherits of the codes, a calculation program has been compiled using Newton iteration methods to solve the expressions presented in the codes. Then, basing on the geotechnical information in the Yangtze River mouth region, the ultimate bearing capacities of layered foundations have been computed by the program and the predictions from three methods have been compared each other. The results show that under the same geotechnical conditions and similar loading conditions, the developed Sokolovski methods shall provide the largest bearing capacity values among three methods; while the bearing capacity value from Hansen 69’s methods shall be smallest.

Key words: harbor engineering, ultimate bearing capacity, layered foundation, Newton iteration methods