Abstract: In recent years,more and more hydraulic projects are built on the infinite deep pervious foundation and many of them take the hanging cut-off walls to solve the seepage control of dam foundation problems.But as for the seepage calculation of these dams,there is not any accurate theoretical formula.As a result,approximate formulas or empirical functions are often used.In this paper the conformal transformation method is used to get the inferential reasoning formulas: seepage pressure formula,seepage discharg...