Stabilizing rammed earth walls as a sustainable construction method with eco-friendly material: a case study

Rammed earth walls are known as sustainable and eco-friendly construction methods, constructed by the local soil in the temporary framework. Generally, the unstabilized soil does not have suitable compression and tension strength for construction. Ordinary Portland cement and lime are frequently used materials for soil stabilization. Regarding the environmental drawbacks of cement as a frequently used, affordable, and available material, it is essential to use eco-friendly material for soil stabilization. In this study, the mechanical behavior of the soil activated by sodium hydroxide, as an eco-friendly material, has been investigated, and the results compared with cement stabilized soil. Unconfined compressive and Brazilian tests for determining the compressive and tensile strength of the rammed earth were performed on the stabilized specimens. The specimens were prepared at different conditions of curing condition, curing time, and binder content. Results indicated that the slag stabilized specimens resulted in more compressive and tensile strength than cement stabilized soil. The superb improvement performance was observed at hot-dry condition, where is a suitable improvement strategy for the arid climate of Iran as well as water scarcity. The soil stabilizing with slag resulted in outstanding improvement efficiency; however, it increased soil brittleness which is not suitable for seismic behavior and may cause a sudden failure in the soil.