Possibility of using different types of Egyptian serpentine as fine and coarse aggregates for concrete production

Abstract

This work is the first attempt to study the possibility of incorporating three different types of Egyptian serpentine aggregates (antigorite, lizardite and chrysotile) with different serpentinization grades as fine and coarse aggregates for normal concrete production. The results of physical and mechanical tests for each type of aggregate were compared to the others. In addition, the effect of serpentinization grade on their mineralogical composition, physico-mechanical and morphological properties of was evaluated and compared. The results were analyzed by using sophisticated tools such as X-ray diffraction, thermogravimetry/differential thermogravimetry and scanning electron microscopy. The results revealed that the physical, mechanical and microstructural properties of serpentine-based concretes were negatively influenced by the progress of serpentinization and deformation processes. The antigorite aggregate showed the lowest serpentinization grade compared to the others (i.e. lizardite and chrysotile). Thus, the antigorite-based concrete revealed better physical and mechanical properties as well as a condensed interfacial transition zone than those of lizardite- and chrysotile-based. Therefore, the results of this study indicated that antigorite is the most appropriate serpentine aggregate to be used in normal concrete production, however, more tests on the durability of such concrete are needed.