Analytical Framework for Geosynthetic Reinforced Earth Structures: Part I — Ideal Approach

The design objective of geosynthetic reinforced earth structures is to determine safe and economical layout and strength of reinforcement. The two companion papers outline two complementary approaches that satisfy this objective. The approaches are based on limit equilibrium analysis. The analysis considers the interaction of soil-geosynthetic and the interaction among reinforcement layers. The end result ensures sufficient length and strength of reinforcement. It also considers the required strength at its front end at the connection to the facing units. This paper shows an approach that produces the required tensile resistance of the geosynthetics so as to render the same factor of safety everywhere. This approach yields the "demand" aspect in design and therefore is considered fundamental in the context of soil reinforcement. It is an ideal approach that is providing a baseline solution. The second approach, presented in the companion paper, considers the "supply" or the existing strength of reinforcement and renders the resulting safety factor everywhere. This approach is the practical one as it matches the supply with the demand via safety factors. While the second approach is not strictly novel, the companion paper demonstrates how it can be used effectively and objectively utilizing color-coded safety maps to optimize the reinforcement length and strength.