Experimental Investigation on Lightweight and Lime Stabilized Earth Composites

An experimental investigation on different clay-based plasters with straw (lightweight plaster) and lime (stabilized plaster) was carried out. The aim of the study was to increase the knowledge on earthen materials in terms of final performance in building applications. In the first part of the study different thermal and hygric parameters were measured: thermal conductivity, specific heat capacity, sorption capacity, water vapour permeability. Furthermore, in order to test the suitability of the unfired clay as mortar, an analysis on the mechanical strengths was carried out, measuring the compressive and the bending strength. The results show, on one hand, that when straw is added to the basic mixture a significant improvement of the sorption capacity occurs, while, the addition of lime enhances the thermal properties. On the other hand, no significant improvement of mechanical strengths can be appreciated when using these additives.