Modeling of reinforced concrete beams strengthened in shear with CFRP: Microplane-based approach

Numerical studies of reinforced concrete (RC) beams strengthened in shear with Carbon Fiber Reinforced Polymer (CFRP) are the topic of this paper. The aim is to validate a numerical approach, which is based on the microplane model for concrete and polymer (matrix), and to better understand the stress distribution in CFRP when the concrete crack initiates and propagates. The numerical study is supported by results of experimental tests [1], regarding 10 beams reinforced with different technological solutions in terms of strength and ductility. This study focuses on the analysis of two RC beams, the first without FRP and the second completely wrapped with CFRP. The numerical 3D finite element (FE) analysis are carried out using the FE code MASA [2] that is based on the microplane model for concrete and FRP. It is shown that the model reasonably well replicates the test results and gives useful information related to damage propagation inside the CFRP.