Structural capacity of rammed earth in compression

Rammed earth walls are formed by compacting subsoil in thin layers inside temporary supporting formwork. An ancient form of construction, rammed earth has in recent years, together with other earth building methods, been increasingly used structurally in a range of contemporary buildings in many countries around the world. Though current structural design procedures for earth walls, including rammed earth, in general use provisions based on structural masonry standards, this approach has never been satisfactorily validated. This paper presents experimental results from material and large-scale testing and develops a simple theoretical model, applied to rammed earth columns subject to concentric and eccentric axial compression loading. An analytical model, using a basic strut theory, shows favorable correlation with the experimental results for all load eccentricities.