The method of Zero Extension Lines (ZEL) has been used to evaluate the static and seismic active lateral earth pressure on an inclined wall retaining c back ll. The equilibrium equations along the zero extension lines have been solved using the nite di erence method. A computer code is prepared to analyze the retaining wall, calculate the ZEL network and the distribution of the active lateral earth pressure behind the retaining wall. The total active force on the retaining wall was de ned as the lateral earth pressure coe cients due to the soil unit weight, the surcharge, and the soil cohesion. The variations of the active lateral earth pressure coe cients with changes in di erent parameters, such as the inclination of the earth and wall, the friction angle of the soil, the adhesion of the soil-wall interface, the horizontal and vertical pseudo-static earthquake coe cients, have been obtained. The results have been obtained for soils with associated and non-associated ow rules. The e ect of the dilation angle has also been considered. The results obtained in this study are very close to those of other methods and con rm that the ZEL method can be successfully used to evaluate the lateral earth pressure of retaining walls.

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