Abstract: The interaction between the earth berm and the retaining structure is analyzed. A simplified method is proposed to consider the effect of earth berm on the retaining pile based on the principle of elastic-reaction method. Calculating results show that with the same earth berm height, the displacement and bending moment of retaining pile can be reduced with the decrease of grade of earth berm or the increase of width of earth berm. But finally they will remain constant when certain grade of earth berm or width of earth berm is reached. The soil condition of earth berm also plays an important role for earth berm to reduce the displacement and bending moment of retaining pile. Well dewatering before excavation, protection of earth berm from being disturbed during excavation and prevention of earth berm from rain during and after excavation are important for earth berm to work . The earth berm can be treated with grouting or DMM when necessary. Case histories show that the results obtained by the suggested method agree fairly well with the field measured data. The application of earth berm in a large excavation project, where horizontal supporting system is no longer necessary, can save considerable cost and reduce construction period.

Key words: elastic-reaction method, finite element method, earth berm, retaining structure