Technological properties of a self-bloating clay and expanded-clay aggregate for the production of lightweight concrete

The global interest in an increasingly sustainable economy, with a reduction in the consumption of raw materials and energy, can be supported by the growth in the use of lightweight concrete (LC) produced with expanded-clay aggregates (EA). The main qualities of natural self-bloating clay for the production of EA were studied, analyzing the parameters that determine the expansion during firing, which influence EA size, mechanical strength, density, and water absorption. After this step, the production and characterization of the LC were carried out. EA characteristics showed a strong influence on the mechanical strength and the main technological properties of the LC. The results pointed out the necessary attributes that clay (and EA) must have for LC production. These attributes can also be achieved by mixing different clays (blend type), which can enhance the production and use of LC with EA worldwide.