In the translational displacement mode

a stress of wedge soil between rigid retaining wall and sliding surface

which is in the passive state of limit equilibrium

is analyzed. Considering the horizontal equilibrium of the soil between the wall and the slip surface

the formula of passive earth pressure coefficient and the angle of failure line to horizontal are obtained by using the principle of soil arching effect. According to the equilibrium equation considering the static equilibrium conditions of horizontal unit of soil

the formula of the passive earth pressure distribution

the resultant earth pressure and the application point of resultant earth pressure on retaining wall are respectively set up. After comparing the computed result using the method mentioned above with the experiment results and the results obtained on the basis of Coulomb and Rankine theories

it is demonstrated that the calculating results agree well with the experimental results; and thus the calculating method obtained is verified rational.