Characterization of rammed‐earth materials from the XVIth century Badii Palace in Marrakech, Morocco to ensure authentic and reliable restoration

Abstract

AbstractThirty rammed‐earth and coating materials collected from the Badii Palace wall in Marrakech were investigated for their particle size, chemical, and mineralogical characteristics. This was done in order to assess the original methods employed—and the provenance of the earth products used—during the Saadian period (XVIth century) construction of the palace. Differences in composition between the rammed‐earth and coating materials (and comparison with the local raw materials) suggest a different origin for these two materials. A high compositional similarity between the coating material and the corresponding rammed‐ earth is observed for the samples collected from well‐preserved walls. However, incompatibility between rammed earth and coatings was observed in many parts of the wall where the original coated materials have deteriorated by natural weathering and by the corrosive action of atmospheric pollution. The composition of coating material currently used for restoration shows the same incompatibility with the substrate and this is probably related to the same degradation problems. Finally, the influence of the semiarid climate in the degradation process is discussed. This study indicates constraints on the selection of the most suitable materials for sustainable restoration of these historic buildings.