Painéis sanduíche com núcleo de concreto leve contendo endocarpo de dendê e faces cimentícias reforçadas com fibras curtas de sisal

Abstract

The use of sandwich panels is presented as a good alternative in civil construction, because, in addition to having low weight and high strength, they can be prefabricated, facilitating transport and assembly on site. The general objective of this research was to develop a sandwich panel with a light concrete core containing agro-industrial residue and faces in cement material composed with vegetable fibers. In the composition of light concrete, palm endocarp was used to replace conventional coarse aggregate. The endocarps were previously cleaned and crushed before being inserted into the matrix. Four different compositions were tested for the concrete in order to find a proportion of endocarp and water that would promote a concrete with low density and satisfactory strength. The endocarp was tested in the mixtures in the proportions of 50%, 100% and 150% in relation to the binder mass and the w/aglo content at 0.35 and 0.45. The panel faces were manufactured with mortar reinforced with short sisal fibers. These fibers were hornified before being inserted into the matrix, seeking to avoid dimensional variation and, consequently, the loss of adhesion at the fiber-matrix interface. All the tested mixes for the concrete resulted in a material with low density, in which the specific mass was below 1504 kg/m³. The highest value of compressive strength obtained for the concrete was 18.05 MPa. The results found for the panels followed the same behavior as the core for most of the tested properties. The specific mass of the panels did not exceed 1480 kg/m³. Regarding the mechanical behavior, for the longitudinal axial compression, the value of 12.81 MPa was obtained. The concrete and the panel that presented the best results were those made with 100% endocarp content and 0.35 w/aglo factor. In this way, it is concluded that it is possible to make concrete with low specific weight using the endocarp of palm oil, promoting a new use and increasing the added value of this residue.