Title

How Do Concrete Rheology, Tribology, Flow Rate and Pipe Radius Influence Pumping Pressure?

Abstract

Finding the critical factors that influence the pressure during pumping of concrete has been investigated for years. From fluid mechanics, the relationship between pressure and flow rate, radius or viscosity is known. In the practical guidelines for pumping of conventional vibrated concrete (CVC) the viscosity term is replaced by the concrete yield stress. However, recently, the influence of viscosity on pumping pressure has been reevaluated for self-consolidating concrete (SCC). In this paper, the influence of concrete rheology, tribology, flow rate and pipe radius on pumping pressure are discussed, based on full-scale pumping tests. The concrete mixtures varied from pumpable CVC to segregating SCC. The influence of flow rate and viscosity on pumping of concrete has been confirmed. It is also shown that with a 20% decrease in pipe radius (from 125 to 100 mm), the pumping pressure can be roughly doubled. An increase in yield stress also increases the pumping pressure, but its influence is only visible when the viscosity is approximately constant. The total flow resistance in the tribometer also appears to correlate well with the pumping pressure, proving that the developed tribometer mimics quite well the flow of concrete in a pipe.

Department(s)

Civil, Architectural and Environmental Engineering

Comments

The authors would like to acknowledge Sodamco Holding S.A.L. for the financial support of the research project, the NSERC Industrial Chair 363837-07 on high performance flowable concrete with adapted rheology at the Universite de Sherbrooke, and the technical staff of the cement and concrete research group at the Universite de Sherbrooke for the construction of the tribometer and the help with the execution of the experimental program.

Keywords and Phrases

Concrete mixtures; Concretes; Elasticity; Flow rate; Fluid mechanics; Optical pumping; Pressure; Rheology; Tribology; Viscosity; Yield stress; Conventional vibrated concrete (CVC); Critical factors; Flow of concretes; Flow resistance; Practical guidelines; Pumping pressure; Radius; Self-consolidating concrete; Pumps; Pressure; Pumping

International Standard Serial Number (ISSN)

0958-9465

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2016 Elsevier, All rights reserved.

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