Formulation d'un mortier de terre stabilisé pour le revêtement mural

Abstract

This Master's thesis is devoted to the study of the formulation and stabilization of raw earth mortars intended for use as wall coatings in the eco-construction sector. The main objective is to overcome the low water durability and dimensional instability of raw earth by valorizing local resources from the region. The experimental program consisted of characterizing a marly clay from Remchi and a fine sand from El Bouihi, then formulating different earth-sand matrices subjected to three types of treatment: without addition, stabilized with 5% lime, and stabilized with a binary mixture of 5% lime + 5% pozzolan. The results in the fresh state show that the lime-pozzolan combination effectively controls plastic shrinkage. In the hardened state (after 28 days), the tests highlight a remarkable textural optimum for the formulation composed of 45% clay, 45% sand, 5% lime, and 5% pozzolan. This optimized eco-material exhibits a maximum compressive strength of 3.12 MPa, a reduced drying shrinkage of 0.90%, and excellent abrasion resistance. Furthermore, when exposed to water, while the control series (0% addition) dissolve instantly, the lime-pozzolan formulation maintains perfect physical and geometrical integrity due to the development of pozzolanic reaction products. Finally, thermal characterization reveals low thermal conductivity, conferring excellent insulating properties to this coating. This work thus scientifically validates a raw earth mortar formulation that is durable, resistant, and ecological.