Study of the crack pattern and its evolution by DIC of RC beams externally reinforced with TRC and CFRP

Textile Reinforced Cements (TRC) are emerging as an external reinforcing material for concrete structures. Especially the high fibre volume fraction TRCs are investigated by researchers as an alternative for the already established Carbon Fibre Reinforced Polymer (CFRP) strips due to their high mechanical performances, their advantages related to fire safety and their relatively low cost. The application of an external bending rein-forcement on a reinforced concrete beam will considerably influence the cracking behaviour of this beam, with potential benefits for the concerning serviceability limit state. An extensive experimental study of this influ-ence and the difference between the different reinforcing materials (CFRP and TRC) is performed in this pa-per. To measure the crack pattern and its evolution, this paper presents the use of the Digital Image Correla-tion (DIC) technique. Based on these DIC measurements the bending cracking behaviour of reinforced con-crete beams with spans of 0.6 and 2.3 meters is studied. For the small scale beams, the paper shows that the TRC-reinforced beams exhibit a similar crack pattern and evolution to the CFRP-reinforced beams, while for the larger scale beams the TRC-reinforced alternative exhibits a more favourable cracking behaviour. The ef-fectiveness of the DIC measuring technique to monitor the cracking behaviour of externally reinforced con-crete beams is hereby also demonstrated.

ISBN:978-1-138-02843-2

Publication year:2015