Characterization and properties of elephant grass ashes as supplementary cementing material in pozzolan/Ca(OH)(2) pastes

Author(s)

Nakanishi, Erika Y. ^[1] ; Frias, Moises ^[2] ; Martinez-Ramirez, Sagrario ^[3] ; Santos, Sergio F. ^[4] ; Rodrigues, Michelle S. ^[1] ; Rodriguez, Olga ^[2] ; Savastano, Jr., Holmer ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Anim Sci & Food Engn, BR-13635900 Pirassununga, SP - Brazil

^[2] Eduardo Torroja Inst IETcc CSIC, Madrid 28033 - Spain

^[3] Matter Struct Inst IEM CSIC, Madrid 28006 - Spain

^[4] Sao Paulo State Univ, Fac Engn, Dept Mat & Technol, Guaratingueta, SP - Brazil

• Document type: Journal article
• Source: CONSTRUCTION AND BUILDING MATERIALS; v. 73, p. 391-398, DEC 30 2014.
• Web of Science Citations: 21

Abstract

This work presents the behavior of two elephant grass ashes, as pozzolans, elephant grass cameroon (EGC) and napier (EGN), calcined under controlled conditions (700 degrees C). The ashes were initially submitted to a chemical treatment with HCI in order to reduce the potassium content. Both ashes showed high pozzolanic activity after 7 days of curing, with at least 85% of fixed lime. The thermogravimetric and micro-Raman analysis in elephant grass ashes/Ca(OH)(2) pastes confirmed that the main hydrated phases during the pozzolanic reaction consisted of CSH gels, by the weight loss between 60 and 300 degrees C in TG analysis and the band at 680 cm(-1) in Raman spectrums. Based on the achieved results, it is possible to conclude that elephant grass ashes can be used as supplementary cementing materials. (C) 2014 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 13/50790-8 - Non conventional cement-based materials developed with industrial wastes as a contribution for a more sustainable industry
• Grantee: Holmer Savastano Junior
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/16842-5 - Waste ashes from the burning of the elephant grass (Pennisetum purpureum) as pozzolanic material for the partial substitution of the ordinary Portland cement
• Grantee: Erika Yukari Nakanishi
• Support Opportunities: Scholarships in Brazil - Master
• 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