CSA as A Revisited Vernacular Technique for Earth Stabilization

Abstract

The Calcium Sulfoaluminate (CSA) is presently receiving a lot of interest in the building sector. It is being used to produce CSA-Cements, which generates less CO2 than Ordinary Portland Cement (OPC), but still requires the production of clinker at high temperature. For the moment, its application is mainly limited to China. On the other hand, the considerable interest in modern earth-based building materials has led to the increase of new types of products such as precast earth, prefabricated earth panels and boards on the market. Their major drawbacks are the low water stability and moderate strength leading to cement stabilization, which as a consequence reduce their environmental advantage. This paper deals with the rediscovery of a vernacular technique of producing CSA for a new stabilized earth-mixture. The first laboratory analyses on this mix-design have proven a high water-resistance. Furthermore, the results show a remarkable increase in compressive strength. Finally, the characterization of the stabilization effect has been performed through X-ray powder diffraction patterns (XRD) and clearly identify the production of ettringite using very low CO2 intensive raw materials. These results open a new avenue for earth stabilization and secure the implementation of this material in the conventional construction industry.