Optimization of Shear Retrofitting of RC beams via Non-linear Numerical Analysis
NRC Grant No: 17-047
Research Institute: University of Peradeniya
Area of Research: Structural Engineering
Summary
Reinforced concrete (RC) structures in service could fail devastatingly due to lack of shear strength. In the context of the buildings and infrastructure of the country are mainly made of reinforced concrete, identification of such potential damage is extremely vital. The structures in service may lack shear strength due to numerous reasons including: increases in the applied loading, changes in use, reinforcement corrosion, or less conservative shear designs based on earlier design codes. Amongst potential remedial actions, shear retrofitting is currently considered as the most promising approach to address structural shear deficiency in the perspective of economy, time and sustainability.
The country is currently moving towards massive development, undoubtedly the existing structures are subjected to higher levels of loading than in the past. Moreover, still most of the structures are fairly old, these have probably been designed based on obsolete design guidelines. And also, the demand for durability (e.g. cover, concrete quality) was not tight in the past when compared with the current durability requirements. Hence there is a high possibility to presence of corroded/weak reinforcements in the existing structures. It is obvious that a national demand for shear retrofitting would arise in near future. In this context, the proposed investigation into find the optimum strengthening configurations for a promising shear retrofitting system possesses a high national relevance. At the successful completion of the project, design guidelines can be established on optimum shear retrofitting. It will be a smart package for the designers (e.g. for RDA) to implement successful and efficient shear strengthening on structures in service at the lowest cost.
Objectives
1. Verify the potential of a non-linear FE modelling package MIDAS to model the behavior of RC beams retrofitted with CFRP straps.
2. Identification of the sensitivity ofCFRP number of straps, strap locations, strap stiffness, and strap prestress towards the shear enhancement.
3. Identification of optimum strengthening configurations via non-linear numerical analyses.
4. Verification of the findings on the optimum configurations through an experimental series.