Assessment of pressure distribution during Squeeze-flow of rendering mortars

• Grant number: 12/18952-5
• Support Opportunities: Regular Research Grants
• Start date: December 01, 2012
• End date: May 31, 2015
• Field of knowledge: Engineering - Civil Engineering - Construction Industry
• Principal Investigator: Rafael Giuliano Pileggi
• Grantee: Rafael Giuliano Pileggi
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated researchers: Fábio Alonso Cardoso

Abstract

The squeeze-flow is a rheological test based on the compression of a cylindrical sample between two parallel plates and has been used, in addition to rotational rheometry, as a complementary method for characterizing fresh mortars. As a result, the squeeze-flow testing method for rendering and masonry mortars was recently standardized (ABNT NBR 15839:2010). During squeezing-flow of mortars phase separation is likely to occur due to the multiphase nature of the material and the characteristics of the method, therefore it must be measured and considered for an adequate analysis of the rheological behavior. For this reason, a gravimetric-based methodology was developed for measuring the liquid-solid separation induced by the test and, then, allowed for a substantial progress of the knowledge related to the squeeze-flow of mortars. However, this methodology provides information regarding the phase distribution only before and after the test, but not what happens during the flow. Thus, the present research project intends to assess the pressure distribution during the squeeze-flow of rendering mortars and to associate theses measurements with the phase segregation results obtained by the gravimetric method already established. This information will be useful to better understand the role of phase separation during flow, as well as, to associate the segregation likelihood with the formulation characteristics of the mortars. A system based on thin and flexible sensors will be required (as described in the budget section) for the assessment of the dynamic pressure distribution. The system proved to be efficient for the use in association with squeeze-flow according to previous tests conducted at Poli-USP. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CARDOSO, FBIO A.; FUJII, ALESSANDRA L.; PILEGGI, RAFAEL G.; CHAOUCHE, MOHEND. Parallel-plate rotational rheometry of cement paste: Influence of the squeeze velocity during gap positioning. CEMENT AND CONCRETE RESEARCH, v. 75, p. 66-74, SEP 2015. (11/00948-9, 12/18952-5, 13/27121-2)

GRANDES, FRANCO A.; SAKANO, VICTOR K.; REGO, ANDRESSA C. A.; CARDOSO, FABIO A.; PILEGGI, RAFAEL G.. Squeeze flow coupled with dynamic pressure mapping for the rheological evaluation of cement-based mortars. CEMENT & CONCRETE COMPOSITES, v. 92, p. 18-35, SEP 2018. (11/00948-9, 12/18952-5)

GRANDES, FRANCO A.; SAKANO, VICTOR K.; REGO, ANDRESSA C. A.; REBMANN, MARKUS S.; CARDOSO, FABIO A.; PILEGGI, RAFAEL G.. Rheological behavior and flow induced microstructural changes of cement-based mortars assessed by Pressure Mapped Squeeze Flow. Powder Technology, v. 393, p. 519-538, NOV 2021. (11/00948-9, 14/50948-3, 12/18952-5)