An algorithm for the evaluation of active thrust for backfill with irregular profile

This paper presents an algorithm for the calculation of the active thrust of backfill with an irregular profile acting on retaining walls. The problem is addressed with Coulomb's method, assuming that the slip surface delimiting the thrust wedge is linear in form and considering equilibrium of forces. The thrust is expressed as a non-linear function of the inclination of the slip surface and has corners, corresponding to the vertices of the piecewise linear surface describing the topographic profile of the backfill, and jumps in connection with the points where line surcharges are applied. The maximum thrust is obtained by differentiating the thrust inside each segment between two successive vertices and inspecting the function in the vertices.