“Soil arching” for piled embankments: insights from stress redistribution behaviour of DEM modelling

For piled embankments, it is widely recognised that the majority of embankment load can be transferred to the piles through the “soil arching” mobilised in the embankment. To date, no consensus has been reached on the shape and composition of the “soil arching”. In light of this, a total of 131 2D trapdoor-like discrete element method models were conducted in this study to present the soil arching effect, stress state and deformation behaviours of the piled embankments. Then, in-depth discussions on the composition and mobilisation mechanism of “soil arching” were performed. The horizontal stress concentration caused by the lateral extrusion of embankment fill was considered to be the composition of the “soil arching”, while the vertical stress redistribution is only the result of load transfer induced by the “soil arching”. Afterwards, the criterion that comprehensively considers the redistribution behaviours of the vertical and horizontal stresses was proposed to determine the feature parameters of “soil arching”.