Per: MARKSSUEL TEIXEIRA MARVILA (UFV - CRP), Thiago Ranilson Caixeta Silva (UFV - CRP), Luiz Arthur Silva de Aquino (UFV - CRP), Marília Gonçalves Marques (UFV - CRP), Leonardo Carvalho Mesquita (ufv - crp), afonso rangel garcez de azevedo (UENF)
Abstract:
Due to the great potential for replacing synthetic fibers with natural fibers, several studies have been carried out aiming to reconcile the growth of the construction industry with sustainable development. Therefore, the objective of this research was to compare three different alkaline treatments on corn straw fiber incorporated in cement and lime mortars for application in covering and laying walls and ceilings. Cylindrical specimens measuring 50x100 mm were made using 0%, 2.5% and 5% natural fibers and fibers treated with sodium hydroxide (NaOH), potassium hydroxide (KOH) and calcium hydroxide (Ca(OH)2) for the composition 1: 1:6:1.55 (cement: lime: sand: water). For the hardened state, the mixtures were evaluated for compressive strength, water absorption, density and porosity, and for the fresh state for their consistency. Chemical, physical and mineralogical characterizations of the fibers were carried out. For the chemical characterization of the fibers, an increase in crystalline cellulose was found from 59.03% to 63.50% (NaOH), 62.41% (KOH), 60.40% (Ca(OH)2), which favors fiber resistance. The water absorption results showed that the mortar containing the treated fibers presented lower values compared to the natural fiber, being a positive point for mechanical resistance. Another positive point that alkaline treatments presented was the reduction in the impurity content of the natural fiber, mainly the treatment with sodium hydroxide (NaOH), with a reduction of 4.69%. Thus, it can be concluded that the treatments improved the properties of the fiber, enabling its use in mortars for covering and laying walls and ceilings. It is worth mentioning that treatment with sodium hydroxide (NaOH) proved to be more efficient in the different properties evaluated
