Finite element analysis of strengthened RC beams in shear with aluminum plates

Abstract

This paper presents the development of a 3D nonlinear finite element (FE) model to capture and predict the response of shear deficient simply supported reinforced concrete (RC) beams strengthened externally with aluminum alloy plates. Five FE models were developed based on experimental tests conducted by the authors in a previous investigation. The experimental program included four RC beams strengthened in shear with externally bonded structural aluminum alloy plates of grade 5083–0 and tested under four-point loading to failure. The use of this material instead of the conventional fiber reinforced polymer (FRP) materials seemed to be very promising in enhancing both the strength and ductility of the strengthened specimens. The beams were designed to fail in shear and then strengthened with aluminum alloy plates with different strip spacing and orientation. The developed FE models have exact geometry, nonlinear material properties and boundary conditions to that of the experimental specimens. The FE models employed material constitutive laws for the concrete in tension and compression, yielding of the aluminum plates and flexural steel reinforcement. The developed FE models also incorporated the interfacial bond behavior at the aluminum concrete interface. The predicted FE results for the load–midspan deflection are compared to the measured experimental data. Close agreement was found between the predicted and measured results at all stages of loading for the tested specimens. For the maximum load and maximum mid-span deflection, it is observed that the Mean Absolute Percent Error (MAPE) of the prediction for the five specimens is 1.19% and 4.31% and the Normalized Mean Square Error (NMSE) is 0.0005 and 0.004, respectively. It could be concluded that the developed FE model could be used in future investigations to predict the performance of shear deficient RC beams externally strengthened with aluminum alloy plates with different configurations and orientations.