Seismic Design of Earth-Retaining Structures

Earth-retaining structures provide support to excavations or earth fills: the earth pressure is either transmitted to the soil located below the foundations of the structure, as in gravity retaining walls, or balanced by a combination of horizontal passive forces in the ground and the reaction forces of additional structural elements, as in the case of embedded retaining structures. Seismic forces have a detrimental effect on these structures, producing an increase in the earth pressure and a decrease in the available soil resistance. Commonly, the seismic design of an earth-retaining structure is carried out using a pseudo-static approach, in which the seismic forces are derived from a uniform acceleration field and are applied statically to the soil-structure system. This approach has the advantage of being relatively simple to implement, but the rationale for the choice of the constant acceleration values needs careful consideration.