Reinforced Soil: An Orthorhombic Material

The reinforcement of a soil mass is simulated by a series of parallel, equally spaced sheets occurring in a single set or in two or three orthogonal sets. The behavior of the reinforced soil mass under working load conditions can be analyzed by applying, repeatedly in the cases where there are two or three sets of reinforcement, a theory that defines the equivalent homogeneous material that can represent a sequence of alternating orthorhombic layers. The properties of the equivalent materials can be used to calculate stress distributions from which the stresses in the soil and reinforcement components can be determined. In the case of thin, stiff reinforcements, the properties of the equivalent materials are found to depend on reinforcement terms that are products of relative thicknesses and relative moduli. When the reinforcement is in the form of meshes or strips, and the soil has pseudo-isotropic properties, the properties of the equivalent materials are simple functions of the reinforcement terms. A numerical example indicates the importance of reinforcement alignment and type, i.e. mesh or strip.