Effect of Construction Sequences on the Behaviour of a Backfilled Retaining Wall

Abstract—Backfilled L-shaped retaining walls are considered as complex types of geotechnical structures, which are particularized by the fact that they are not only supported by the soil, as is the case with foundations, but also loaded by the soil. Actual design methodology does not take into account the construction sequences which simulate the process by which the soil and the retaining wall are brought together. However, in reality, at least during the backfilling process, the retaining wall undergoes many displacements that are not so far considered in the design. In the present investigation, the influence of the construction sequences on the behaviour of an L-shaped stiff retaining wall is investigated with a numerical model. For validating the proposed numerical model, reference was made to the results of a centrifuge experiment conducted on a reduced prototype. The numerical analysis shows that for the type of wall and soil investigated, considerable displacements of the wall (rotation and translation) occur during the backfilling process. The rotational movement of the wall is not occurring around the toe as it is usually assumed in design practices, but it follows a total displacement path of the toe. It is recommended that a better estimation of the rotation (s) of the wall is necessary to reach the state in which active earth pressure can be fully mobilized.