In granular matter, stresses are transmitted from grain to grain along paths or chains of contact forces, which do not include all grains. In this paper, the force network is simplified by the linearization of the paths, and the macroscopic stresses are obtained associating a band of soil to each path. To resemble the granular packing of the soil, a set of inclined and conjugate bands is assumed. The method consists of decomposing the weight of the elemental rhomboid into unitary forces, and adding them along an associated band. The resultant force acting on the back face of the retaining wall is found as the vector sum of the two force chains. The force chain directions are obtained considering the overall kinematics of the wall rotating about the top, and the subsequent kinematics of the grains in a primitive rhomb, being that lower grains are required to rotate with respect to upper grains. This leads to the formation of contact force chain against the wall following a passive direction, whereas the other force chain remains at the at rest direction. Since the soil is in dense state, a shear band separates the mobilized wedge from the fixed zone in the backfill soil mass. This shear band, which depends on the inclination of the soil surface, is assumed to be linear. Since the angle of the passive force chain is greater than the failure angle, the lateral pressure becomes bilinear, with the maximum value near the top, in agreement with the experimental results of several authors.