Supercritical carbonation treatment on extruded fibre-cement reinforced with vegetable fibres

Author(s)

Santos, Sergio F. ^[1] ; Schmidt, Rene ^[2] ; Almeida, Alessandra E. F. S. ^[2] ; Tonoli, Gustavo H. D. ^[3] ; Savastano, Jr., Holmer ^[2]

Affiliation

^[1] UNESP, Dept Mat & Technol, BR-12516410 Guaratingueta, SP - Brazil

^[2] Univ Sao Paulo, Dept Biosyst Engn, BR-13635900 Pirassununga, SP - Brazil

^[3] Univ Fed Lavras, Dept Forest Sci, BR-37200000 Lavras, MG - Brazil

• Document type: Journal article
• Source: CEMENT & CONCRETE COMPOSITES; v. 56, p. 84-94, FEB 2015.
• Web of Science Citations: 30

Abstract

The objective of this research was to evaluate the effects of supercritical carbonation treatment for 2 h on the main hydrated phases of the cement matrix (calcium hydroxide and calcium silicate hydrate) and durability of extruded fibre-cement reinforced with bleached eucalyptus pulp and residual sisal chopped fibres. The thermal analysis, bulk density, porosity, physical characteristics and mechanical performance were evaluated before and after 200 soaking and drying cycles for following the degradation of the material under accelerated ageing conditions. The higher carbonation rate during the early stage of curing period decreased the porosity by sealing the opened pores around vegetable fibres and, consequently, led to lower water absorption and higher bulk density in the composites. The average MOR-values showed a significant increase in the case of the supercritical carbonated extruded fibre-cement in the initial age and after accelerated ageing. Besides, after 200 soaking and drying ageing cycles, the average values of energy of fracture (gamma WoF) of the carbonated composites decrease only 28%, showing evidences of the preservation of microstructural stability and toughness of the fibre-cement composites after supercritical CO2 treatment. (C) 2014 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 08/04769-9 - Degradation study of cellulosic fibers in cementitious composites: contribution to sustainable constructive materials
• Grantee: Alessandra Etuko Feuzicana de Souza Almeida
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 09/10614-0 - Fundamental mechanical characteristics of non-conventional composites reinforced with cellulose and synthetic fibres: contribution to sustainable building materials
• Grantee: Holmer Savastano Junior
• Support Opportunities: Regular Research Grants
• FAPESP's process: 09/17293-5 - Fracture mechanics applied to the development of non conventional extruded composites reinforced with cellulosic and synthetic fibers
• Grantee: Sérgio Francisco dos Santos
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 10/16524-0 - Fracture mechanics applied to the development of non conventional extruded composites reinforced with cellulosic and syntetic fibers
• Grantee: Sérgio Francisco dos Santos
• Support Opportunities: Scholarships in Brazil - Young Researchers