Design of geosynthetic reinforced column supported embankments using an interaction diagram

Geosynthetic reinforced column supported embankments predominantly utilise two mechanisms to transfer embankment loads towards column heads, soil arching and membrane actions. When undertaking the design of column supported embankments, it is common practice to perform a two-step design, whereby the arching actions are estimated independently of the subsoil deformation and membrane actions. This approach is unable to capture the deformation dependency exhibited by both arching and membrane actions. This paper presents deformation dependent arching and membrane action models and implements them within an interaction diagram. It is shown that an interaction diagram-based design approach is capable of performing an ultimate and serviceability limit state design of a geosynthetic reinforced column supported embankment. In contrast, most existing analytical design methods only consider the ultimate limit state. The proposed method is applied to a design example where the benefits of such a design approach are demonstrated.