Geosynthetic Reinforced Soil (GRS) Walls

5Design of Geosynthetic Reinforced Soil (GRS) Walls

In this chapter we shall address the design of geosynthetic reinforced soil (GRS) walls, including design concepts, design methods, and related issues for both mechanically stabilized earth (MSE) walls with geosynthetics as reinforcement (referred to as GMSE walls) and geosynthetic reinforced soil (GRS) walls. The differences between GMSE and GRS have been explained in Chapter 3. Among current design methods for reinforced soil walls, most are applicable to GMSE walls with a handful of them being applicable specifically to GRS walls. Design methods for MSE walls with metallic reinforcement have been presented elsewhere, e.g., Schlosser and Segrestin (1979), Smith and Pole (1980), and Mitchell and Villet (1987), and will not be addressed here.

This chapter begins with a description of basic design concepts, followed by an overview of design methods. In addition, six recent advances related to the design of GRS walls are discussed in some detail, including:

• required reinforcement stiffness and strengths
• evaluation of pullout stability
• lateral movement of wall face
• required long‐term strength of geosynthetic reinforcement
• connection stability of concrete block facing
• required reinforcement length.

Step‐by‐step design procedures for four design methods are then given, including:

• the U.S. Forest Service (USFS) design method
• the AASHTO ASD design guidance for GMSE walls
• the NCHRP design method for GRS bridge abutment walls
• the ...