Identification of the tensile law of UHPFRC materials from bending tests by means of digital image correlation

Author(s) : Y. Duhamel-Labrecque, L. Sorelli, J. Rethore, F. Baby, F. Toutlemonde, S. Bernardi
Paper category : Proceedings
Book title : UHPFRC 2017 Designing and Building with UHPFRC: New large-scale implementations, recent technical advances, experience and standards
Editor(s) : F. Toutlemonde & J. ResplendinoT.Ch.
Print-ISBN : 978-2-35158-166-7
e-ISBN : 978-2-35158-167-4
Publisher : RILEM Publications SARL
Publication year : 2017
Pages: 231 - 241
Total Pages : 11
Language : English

Abstract: The use of Ultra High Performance Fibre Reinforced Concrete (UHPFRC) requires the use of the tensile law which is commonly identified by inverse analysis from bending tests. The aim of this work is to foster the identification of the UHPFRC tensile law by means of Digital Image Correlation (DIC) analysis in order to account the distribution of multiple cracks, the asymmetric position of the localized crack and the unloading of the micro-cracked parts. A series of unnotched UHPFRC beams with fibre volume content of 1% and 2% were tested under 4 point bending tests (4PBT). The relationships moment-curvature M-X and moment-rotation M- were identified by best-fitting the deflection and rotation over the beam length at all time steps. By considering the rotation compatibility mechanisms, the characteristic length Lch was also estimated. Finally, the UHPC tensile law is estimated from the M-X relation. In agreement with previous methods, the proposed method was able to systematically distinguish strain hardening and softening UHPFRC.

Online publication : 2017
Publication type : full_text
Public price (Euros) : 0.00