Federica Fernandez, Roberta Basile, Maria Teresa Enna, Silvia Germinario, Maria Mangiapane, Roberta Montagno
Abstract
Nowadays the use and experimentation of multi-functional mortars has increased significantly, with interesting applications in the green building and cultural heritage conservation sectors.
The objective of this research was to define the performance and behavior of these materials over time, in order to use them correctly and avoid irreparable damage over time. For the development of this research, lime-based and metakaolin-based plaster mortars (hereinafter called A, B) and lime-based plaster and metakaolin mortars with the addition of TiO2 titanium dioxide (hereinafter referred to as A+, B+) have been tested. The focus of the work was to test methods to accelerate the natural aging of materials, in order to simulate different environmental degradation agents to which the mortar can be subjected in buildings and define specific artificial aging protocols. The mortar samples were examined after exposure to thermal shock cycles in saline solution aerosols, freeze cycles in vapor aerosol and aging by heat treatment at high temperatures. Before and after each artificial aging cycle, weight measurements and macroscopic and microscopic observations were performed in order to evaluate possible structural changes. The characteristics of the mortars were assessed by determination of the apparent volume mass, water delivery tests for total absorption and their self-clearing capacity was measured by methylene blue degradation test under UV irradiation and solar radiation. The results obtained show degradation effects in the mortar samples due to aging after each test and indicate that the mortars added with TiO2 are the most performing ones.
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