Sugar components as a natural reinforcement of earth based construction materials

Abstract

An important part of the world’s population, approximately 3 billion people, on six continents, lives or works in buildings constructed of earth based materials. A research work developed in the Trás-os-Montes e Alto Douro University (UTAD) and focused on the biomimetic study of the Andorinha-dos-beirais bird nest concluded that there is a strong possibility that this bird adds a significant amount of glucose type sugar into the clay material during the building process of its nest. Results from the numerical model of the nest indicated that this natural structural system works mainly in compression, which is in line with inherent properties of earth based materials, with reduced tensile and shear capacity. Experimental tests have shown that an agglutination phenomenon may occur resulting from the building process adopted by the Andorinha-dos-beirais bird. Based on these conclusions, this research work in-tends to analyse the influence of the glucose sugar type addition into the nest structural performance. In this context, compression tests were done varying the liquid phase, sugar percent-age and curing period. Experimental results can be used to sustain the use of this technique in the context of earth buildings construction and can contribute for the future proposal and development of new raw building composite materials.