Influence of perlite on the mechanical behavior, capillary absorption and thermal conductivity of mortars

Abstract

The Algerian soil is rich in natural pouzzolanic materials, such as natural perlite, in the western region more precisely Hammam Boughrara in Maghnia (Tlemcen).  Unfortunately, they’re not yet fully exploited. Perlite, thanks to its chemical components, silica and aluminum, which give it interesting properties, has the privilege of being used as an active mineral additiion in the production of cement. This study contributes to more data on the valorization of perlite as a partial substitute for cement. For this purpose, mortars containing different levels of perlite (0%, 10%, 15%, 20% and 25%) were manufactured. The behaviors of the five formulations in the fresh state (consistency, workability and setting time) and in the hardened state (capillary absorption, thermal conductivity and compressive strengths) were studied.  The results of the experimental study prove that Maghnia perlite has a positive effect on the properties of mortars. The possibility of using it at dosages up to 25% in order to decrease the rate of cement implies an economic and environmental advantage. In addition, long-term satisfactory mechanical strengths behavior for a 20% perlite rate was noted. Furthermore, mortars containing perlite have low thermal conductivity, which highlights the beneficial effect of perlite as a thermal insulator and the importance of enhancing this addition.