Influence of different mixing parameters on fresh properties of ultra high strength hybrid fibre concrete (HFC)

Author(s): F. Dehn, M. Orgass, A. König
Paper category: Workshop
Book title: Fifth International RILEM Workshop on High Performance Fiber Reinforced Cement Composites (HPFRCC5)
Editor(s): H.W. Reinhardt, A.E. Naaman
ISBN: 978-2-35158-046-2
Pages: 243 - 248
Total Pages: 7
Language: English

Abstract: 
In order to optimise the performance of ultra high strength hybrid fibre concrete (HFC) the mix design has to be co-ordinated with the production process. On this account, the influence of varying mixing parameters on the fresh properties of a certain type of HFC with a selfcompacting ultra-high strength matrix and a representative steel fibre content was studied within an extensive research program. For the experiments the use of a high performance mixer was essential. Basically, the investigated HFC contained short straight (2 % by vol.) and long hooked (1 % by vol.) steel fibres. The aim was to produce a flowable hybrid fibre concrete by changing only the mixing parameters. Exemplary, the results for the following mixing parameters are summarized in this paper: mixing order and mixing speed. The composition of the mixture was not changed. From the experimental study a direct interrelationship between the mixing parameters and the fresh concrete properties can be derived by recording all relevant mixer data and testing the fresh concrete properties simultaneously. The paper will emphasize the necessity of implementing rheological tests when projecting such high performance cementitious materials.

Online publication: 2014
Publication Type: full_text
Public price (Euros): 0.00