Influence of flowability, casting time and formwork geometry on fiber orientation and mechanical properties of UHPFRC. (May 2017)

• Record Type: Journal Article
• Authors: Zhou, Bo; Uchida, Yuichi
• Is Part Of: Cement and concrete research. Volume 95(2017)
• Page Start: 164
• Page End: 177
• Publication Date: 2017-05
• Subjects: UHPFRC -- Fiber orientation -- 3D visualization -- X-ray CT -- Flexural properties; Cement -- Periodicals; Cement -- Research -- Periodicals; Concrete -- Periodicals; Concrete -- Research -- Periodicals; Ciment -- Périodiques; Béton -- Périodiques; Cement; Concrete; Periodicals; 620.135
• DOI: 10.1016/j.cemconres.2017.02.017
• Languages: English
• ISSNs: 0008-8846

Abstract

Abstract: In this study, fiber orientation in ultra-high-performance fiber-reinforced-concrete (UHPFRC) with different formwork geometry was evaluated using visualization model concrete and via analysis involving 3D visualization based on X-ray computed tomography (CT). Differences in fiber orientation in the height direction were first reviewed. Furthermore, the influence of flowability and casting time on the fiber orientation and mechanical properties of UHPFRC were examined. The results indicated that flowability dictates eventual fiber orientation in parts close to the surfaces of formwork. The use of UHPFRC with superior flowability results in more fibers being oriented parallel to the longitudinal direction of slabs in comparison to UHPFRC with inferior flowability. It was also found that flowability and casting time can have strong influences on the mechanical properties of UHPFRC. Residual flexural strength after initial cracking exhibited perfect linear dependence on the effective number of fibers at fracture planes.