Abstract: The ultimate foundation bearing capacity is a classic problem of soil mechanics, with a wide range of influ－ ence and a extensive application. The currently adopted Terzaghi’s ultimate bearing capacity formula fails to provide an analytical solution for the parameter Nγ. The empirical formulas proposed by the predecessors are quite different, with unclear basis, it is difficult to get unified. Thus the author obtains the analytical solution of Terzaghi foundation bearing capacity coefficients of Nγ, Nq and Nc with the principle of limit equilibrium, verifies the correctness of the coefficients Nq and Nc along with that of the parameter Nγ in theory and expands the scope of application of Prandtl-Reissner’s formula on the relationship between Nq and Nc. The research result provides useful references for the study and research on the basic theory of bearing capacity.

Key words: ultimate foundation bearing capacity, Terzaghi’s formulas, principle of limit equilibrium, coefficients of bearing capacity