SHEAR-TENSION BEHAVIOR OF FIBER-REINFORCED CONCRETE: A FINITE ELEMENT STUDY USING THE INCLINED PUSH-OFF TEST MODEL

This paper uses numerical simulation to investigate the behavior of fiber-reinforced concrete tested under combined shear and tension. The test setup was based on an inclined push-off test. The numerical simulation was carried out using an in-house finite element package that employs the multi-surface plasticity model for concrete material. Three fiber materials are being investigated: steel fiber, polypropylene fiber (PP), and polyvinyl alcohol fiber (PVA). The stress-strain model for each fiber material was obtained from the laboratory test. The accuracy of the finite element (FE) model was first validated with the available reinforced concrete specimen that was being tested under a push-off test. The numerical simulation found that the push-off model made with steel fiber reinforced concrete (SFRC) responds similarly to plain reinforced concrete (RC) but with a 72.48 % increase in load-carrying capacity. For the PVA-ECC FRC, the load-carrying capacity at the peak displacement of 5.20 mm increased to more than 113.78 %. On the other hand, using PP-FRC can only slightly increase the load-carrying capacity by 8.28 %. In addition, the PP-FRC has a much softer response during hardening due to lower elastic modulus than plain concrete.