Parallel-plate rotational rheometry of cement paste: Influence of the squeeze velocity during gap positioning

Autor(es)

Cardoso, Fbio A. ^[1] ; Fujii, Alessandra L. ^[2] ; Pileggi, Rafael G. ^[1] ; Chaouche, Mohend ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Escola Politecn, Dept Construct Engn, BR-05508900 Sao Paulo - Brazil

^[2] Ecole Normale Super, CNRS, Lab Mecan & Technol, F-94235 Cachan - France

• Tipo de documento: Artigo Científico
• Fonte: CEMENT AND CONCRETE RESEARCH; v. 75, p. 66-74, SEP 2015.
• Citações Web of Science: 5

Resumo

This paper reports an experimental investigation regarding the influence of the squeeze velocity, during positioning of the parallel-plate gap, on the rotational shear flow behaviour of a cement paste. The descent of the upper plate was performed using diverse speeds while the normal force generated due to the compression of the paste was recorded. The slower the plate speed, the higher the resulting normal force. This behaviour was caused by liquid-solid separation, which is more likely to occur at slow squeeze velocities. Phase separation was confirmed by assessing, via microwave drying, the water contents of the trimmed portion of the paste sample and of the portion actually subjected to rotational shear cycles. Owing to the variation of water/cement ratio induced by liquid radial migration, paste's Bingham yield stress and plastic viscosity were significantly affected by squeeze speed, and both rheological parameters presented an inversely proportional relationship with this experimental variable. (C) 2015 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 11/00948-9 - Separação de fases em argamassas: desenvolvimento de método de avaliação e influência sobre o comportamento reológico
• Beneficiário: Fábio Alonso Cardoso
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 12/18952-5 - Monitoramento da distribuição de pressão durante ensaios reológicos de Squeeze-flow em argamassas de revestimento
• Beneficiário: Rafael Giuliano Pileggi
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 13/27121-2 - Squeeze-flow e separação de fases en argamassas: influência da viscosidade da pasta e da distribuição granulométrica
• Beneficiário: Fábio Alonso Cardoso
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado