Flow behaviour of high strength high-performance concrete

• Published in: Cement & concrete composites 1999-12, Vol.21 (5-6), p.413-424
• Main Authors: Yen, Tsong, Tang, Chao-Wei, Chang, Chao-Shun, Chen, Kuang-Hong
• Format: Article
• Language: English
• Subjects: Bingham model; High strength high-performance concrete; Mix proportions; Rheology; Two-point test
• ISSN: 0958-9465; 1873-393X
• DOI: 10.1016/S0958-9465(99)00026-8

The workability of flowable High-Performance Concrete (HPC) is nowadays mainly measured using conventional test methods such as the slump test or the slump-flow test. These single-point tests do not seem sensitive enough to characterize the high-workability of HPC. Due to the fluid consistency and uniformity of fresh HPC, it is possible to describe its flow properties by using a rheological test method. To evaluate the flowability based on rheology, fresh HPC is regarded as a two-phase material composed of a matrix phase and a particle phase. In the study, the effects of materials and proportioning on the rheological properties were investigated experimentally. A new rheometer was established by conducting a two-point test to investigate the flow behaviour of high strength HPC. Test results show that the high strength HPC with good uniformity and without tendency of segregation can possess the properties of rheology according to Bingham’s equation. An increase of the fraction of mortar in HPC can lead to a more distinct the rheological behaviour. Moreover, it is found that the application of a rheological method can provide more stable results than any other test method in describing the flowability of high strength HPC.