Basic theory of reinforced soil

A simple model helps explain the principle that inspired the techniques of reinforced soil (Rimoldi, 2000). Consider the element of soil in Fig. 15.1(a), which is part of an infinite mass the application of a vertical force, Cy, causes a deformation in the element and the consequent horizontal stress, Ch, caused by the lateral compression of the adjacent soil which opposes the deformation. Horizontally, the soil undergoes deformation, e, which is the main cause of local failure. 

Modified from Rimoldi, P., 2000. II progetto di pendii ripidi rinforzati con Geosintetici di rinforzo. In Prontuario di Ingegneria Edile e Strutturale, Ed. UTET, Torino (in Italian). 

With regard to the resistance to shear, in accordance with Fig. 15.2 in a cohesionless soil element, we have (Eq. [15.9])  

Total shear stress = (shear stress generated by the soil alone) 

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