AN OVERVIEW OF SOME CURRENT RECOMMENDATIONS ON THE SUITABILITY OF SOILS FOR RAMMED EARTH

Rammed earth is a sustainable construction material, especially in remote areas where utilising the locally available soil means reduction of costs and environmental impact of construction. Before the soil could be used in construction, testing is required to determine whether it is suitable for rammed earth. Past research studies and current earth building technical documents provide some guidelines for the suitability of soils for rammed earth. Nevertheless, these guidelines are sometimes broad and vague making assessment of the soil difficult. This paper shows the limits of the currently available guidelines and determines whether the recommended assessment criteria are appropriate. From this study, it is evident that more research is needed to understand the effect of water suction, water-cement ratio and mineralogy of clay in the mechanical behavior of rammed earth. Furthermore, suitable tests to assess durability properties (such as erodibility) need to be implemented.