Theoretical modelling and acoustic emission monitoring of RC beams strengthened with UHPC

- Non-linear fracture mechanics model to predict moment capacity.
- Strength based model to predict load deflection response of strengthened beams.
- Classification of acoustic emission parameters to study the progress of crack.
- Effect of reinforcement ratio on AE parameters in RC beams strengthened with UHPC.

In this study, theoretical modelling and acoustic emission (AE) studies are carried out on damaged reinforced concrete beams strengthened with ultra high performance concrete (UHPC). The contributions from the paper include (i) development of an integrated nonlinear fracture mechanics model to predict the moment carrying capacity of composite beam considering (a) stress intensity factors due to cement paste, steel, UHPC and applied load (b) vectorial contributions of crack displacement from external moment, steel and UHPC force (ii) prediction of load deflection response of strengthened beams by strength based model which applies concepts of force equilibrium and strain compatibility method (iii) analysis of the effect of reinforcement ratio on AE parameters from parametric analysis. The presented results can be effectively utilized for designing UHPC thickness and health monitoring of structures strengthened with UHPC.