Finite/discrete element model of tension stiffening in GFRP reinforced concrete

• We described three experiments on the tension stiffening in concrete reinforced with GFRP.
• We compared the experiments with a theoretical model for steel-reinforced concrete.
• We formulated a better-fitting equation for concrete reinforced with GFRP.
• We used FDEM to model the crack propagation in the concrete.
• We demonstrated that the model is capable of reproducing the experimental results.

The purpose of this paper is to investigate the phenomenon of tension stiffening in concrete reinforced with glass fibre polymer (GFRP) bars. The nature of the tension stiffening phenomenon is first described according to theory. Then, the results of an experimental campaign aiming to investigate tension stiffening quantitatively are presented and critically discussed, examining potential factors such as shrinkage that could have affected the measurements. Finally, the numerical models that reproduce the experiments are described and the results compared with both the theory and the experiments themselves. Good agreement is found between model and experimental data.