Pseudo-static coefficient in reinforced soil structures

The selection of the appropriate horizontal seismic coefficient (k(h)) considering the actual conditions governing earth structures is the foremost part of analysis in the pseudo-static approach. In spite of the importance of this issue, no specified criterion has yet been provided to select k(h) for reinforced-earth structures. Therefore in this study, a series of experimental and analytical studies were performed on steel-strip-reinforced soil walls, soil-nailed walls and MSE/soil-nail hybrid retaining walls to reflect the effect of the non-uniform distribution of acceleration along the wall height on the choice of k(h) in reinforced soil structures. In the first step, the values of maximum horizontal acceleration (MHA) corresponding to failure (MHA)(y), the axial force distribution along the reinforcements at the failure stage and the pattern of wedge failure for each reinforced wall were found by shaking table tests. Then, by using a developed pseudo-static approach based on the horizontal slice method with a new formulation and considering the results obtained from laboratory model tests, the distribution of k(h) along the wall height was determined and the average seismic coefficient (k(h))(ave). for all three reinforced soil structures was separately introduced as a function of MHA at different height levels.