Continuum versus Structural Approach to Stability of Reinforced Soil

Two techniques for stability analysis of reinforced soil structures are presented. In the first one, called the continuum approach here, the reinforced soil is first homogenized, and the slip-line method is used to find the limit stress field in an anisotropic continuum. The second, structural approach, considers reinforcement and granular fill as two separate structural components, and the kinematical method of limit analysis is used as the technique of solution. The solutions to critical heights of reinforced slopes are presented as an illustrative example for application of the described techniques. The structural approach proposed here has a clear theoretical interpretation, is easily applicable to any failure patterns, and can be modified to accommodate the nonassociative flow rule for soils. The continuum approach with the slip-line method of solution for stresses was found to be more restrictive and less convenient than the structural approach. The continuum approach is expected to have a wider application, however, in analysis of earth structures with less conventional reinforcements such as continuous filament or for fiber-reinforced soils.