Cementitious composites strengthened with pure eucalyptus fiber and treated with tetraethyl ortosilicate (TEOS 98%)

This paper presents the attainment of higher flexibility and elasticity in a high initial strength (CPV) Portland cement matrix, achieved through the addition of pure eucalyptus fibers treated with tetraethylorthosilicate TEOS 98%. The fibers used were characterized by their morphology through optical microscopy and through the use of anatomic MIPRO software; its water absorption properties were analysed using the TEOS 98% impregnation efficiency test. In order to obtain the composites, cement masses were formulated with the addition of pure eucalyptus fibers and treated at concentrations of 2%, 5% and 10% by weight. The composites were characterised for water absorption, porosity, and modulus of elasticity (MOE), measuring their flexural strength at three points. A comparative analysis was done between the cement-eucayptus fiber composite and a high initial resistance Portland cement mass. The results showed that the highest valores de reforço were achieved in the cement with 2% eucalyptus fiber treated with 98% TEOS, since that cement presented the highest MOE values, presenting more fissure control and energy absorption after cement matrix fracture.