Performance-Based Seismic Retrofit of Existing Reinforced Concrete Frame Buildings using Fibre-Reinforced Polymers: Challenges and Solutions

The need for simple and cost-effective seismic retrofit solutions for existing reinforced concrete (RC) buildings, particularly those designed before the 1970s, prior to the introduction of modern seismic code provisions and capacity design principles has been recognized as a critical socio-political priority at the international level. Similar to what was pursued for the design of new structures, a performance-based approach has to be adopted when assessing the vulnerability and defining the retrofit strategy for existing buildings. In this contribution, an overview of recent evidence-based developments in the field of fibre-reinforced polymer strengthening of existing RC frame systems has been presented. Based on experimental tests, and analytical numerical results as well as experience from on-site applications, particular focus will be given to the discussion on feasibility and efficiency of low-invasive implementation techniques targeting the exterior corner joints of a building in order to guarantee minimum interruption to the functionality of the building.