Physical, mechanical and durability aspects of lime-based coatings with addition of natural zeolite

Abstract

Lime-based renders were usually placed in several layers, each of them having specific role and composition. In this paper, physical and mechanical properties of lime mortars for the final layer (coating) at the age of 90 and 180 days were presented. Durability aspect of the tested mortars was considered through testing of their behavior in the presence of the soluble salts. Four mortar mixtures were tested (one reference mortar and three mortars with partial replacement of lime with natural zeolite). For all mortars tested it can be seen that there was no improvement in strength between two tested ages. Mortar with 30% of lime replaced with zeolite reached higher value of compressive strength and almost the same value of capillary water coefficient as reference mortar. Vapor permeability grew with the increase of the natural zeolite content. Mortars showed good resistivity to the presence of sodium-chloride and developed cracks and loss of compressive strength when exposed to the solution of sodium-sulfate.