TENSILE PROPERTIES OF CONCRETE AND FIBER REINFORCED CONCRETE

Author(s): Zongjin Li
Paper category: Proceedings
Book title: Proceedings of CONSEC13 Seventh International Conference on Concrete under Severe Conditions - Environment and Loading Volume I
Editor(s): Z.J. Li, W. Sun, C.W. Miao, K.Sakai, O.E. Gjørv, N.Banthia
ISBN: 978-2-35158-124-7
e-ISBN: 978-2-35158-134-6
Publisher: RILEM Publications SARL
Publication year: 2013
Pages: 102-108
Total Pages: 961
Language : English

Abstract: The tensile property of concrete and reinforced concrete is important for shrinkage crack control and fracture toughness. However, it is difficult to conduct an experiment to measure a complete stress-deformation curve for concrete due to its quasi-brittle nature. In this study, a relatively new method is introduced. This method employs a digitally controlled closed-loop-testing machine and five control channels. The test portion of the specimen is fully spanned by four LVDTs and quick switch the control mode among the LVDTs is enabled by software. It has been demonstrated that it is always possible to obtain a stable post-peak response provided one ensures that at any time during the test, the feedback used is the LVDT that exhibits, at that time, the largest slope of the response-time curve. An acoustic emission (AE) measurement system of six channels is also used in the experiments. Monitoring of signals from the AE transducers provide valuable information, which help in making decision to switch the control.
The test results show that for plain concrete and FRC with small fiber volume ration the stain localization happens before the peak load and after that the deformation on the specimen becomes non-uniform. Different portion of the specimen may even have opposite direction in deformation. The strain hardening can be achieved for FRC with sufficient fiber volume fraction.

Online publication : 2013
Publication type : full_text
Public price (Euros) : 0.00