Utilization of gypsum from construction and demolition waste in Portland cement mortar.

Reference Presenter Authors
(Institution)
Abstract
04-019 Maria Lucia Pereira Antunes Antunes, M.L.(Universidade Estadual Paulista (UNESP), Instituto de Ciência e Tecnologia, Sorocaba); de Sá, A.B.(Universidade Estadual Paulista (UNESP), Instituto de Ciencia e Tecnologia, Sorocaba); Oliveira, P.S.(Universidade Estadual Paulista (UNESP), Instituto de Ciência e Tecnologia, Sorocaba); Souza, C.d.(Universidade Estadual Paulista (UNESP), Instituto de Ciência e Tecnologia, Sorocaba); Durrant, S.F.(Universidade Estadual Paulista); Rangel, E.C.(Universidade Estadual Paulista); Marques, M.A.(Universidade Estadual Paulista (UNESP), Instituto de Ciência e Tecnologia, Sorocaba); The production chain of construction is tied to social and economic growth of a country, but it is also associated to the exploration of natural resource and the huge generating of waste. This waste is denominated Construction and Demolition Waste (CDW) and it is responsible for a great squander and cost to Brazilian municipalities. However, CDW could be used, reducing the consumption of natural resource and contributing to a better disposal of waste. One of the CDW that may present environmental risk is the gypsum. This one, in inadequate disposal can produce toxic and flammable gases. Focusing this issue, the aim of this work is use gypsum from construction and demolition waste (CDW) to produce cement mortar. The gypsum used in this work was collected in construction from Sorocaba region (S.P.) and it was transformed into powder. Then, this material was characterized as its specific mass and granulometry. The morphology of gypsum waste samples were observed under a Scanning Electron Microscopy (SEM), attached with an energy dispersive X-Ray Spectrometer unit (EDS). Its Chemical composition was determined by X-Ray fluorescence. Some cement specimens were made in proportion 1:3 (cement: sand). Gypsum residue substituted part of sand (in volume) in different percentage 0, 10, 20 and 30%. The mortars were evaluated in their fresh state by consistency index and hardened states by compressive strength. The gypsum residue is free of impurities and its specific mass is 1.1 g/cm³. The specimens showed positive results, having passed the mechanical resistance test (5.5MPa) for substitution of down 30% of the sand. In addition, the tests showed that specific mass was reduced; this is advantageous in field of civil engineering.
<< Back
Copyright © 2019 Metallum. All rights reserved.
Site produced by: SITESP.NET