A generalized computer program for analyzing stability of earth structures reinforced with geosynthetics (geogrids, geotextiles etc.) was developed in this research study. The newly proposed computer program was built in such a way that a reinforced slope stability problem may be analyzed using a variety of limit equilibrium methods including Hopkins', Morgenstern and Price's, Bishop's methods, Raulin's perturbation method, as well as new perturbation methods proposed by the authors of this study. It was shown in the research study that two versions of the Bishop's method were possible in the case of reinforced analyses: the traditionally used version referred to as "incorrect" Bishop's method, and a version that strictly follows the philosophy of the original Bishop's method referred to as "correct" Bishop's method. A comprehensive analysis of different generic examples and case histories was undertaken in the research study using different limit equilibrium methods. It was shown that in an internal stability analysis of reinforced earth structures all statically consistent methods and Bishop's "correct" method provide almost the same values for safety factors. Bishop's "incorrect" method was found to significantly underestimate the factor of safety. It was also shown that the commonly used Tensar® design method tends to be conservative especially for steep slopes. In the case of overall stability of reinforced embankments on soft foundations, most methods led to some violation of admissibility criteria. The least violation of admissibility criteria was observed in a perturbation method proposed by the authors of this research study. Consequently, this method generally yields safety factors that are close to the "right" answers.

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