Strengthening and Repair of Reinforced Concrete Beams Using Concrete Jackets

Abstract

The necessity to rehabilitate a Reinforced Concrete (RC) structure emerges from several reasons such as new safety requirements, change of structure occupancy, incorrect design calculations and/or degradation of materials with time. One of the most commonly used mitigation practices to strengthen and repair RC beams is the application of RC jackets at either one side or three sides of the beams. The use of these jackets to improve the flexural performance of RC beams is investigated in this study. An iterative incremental algorithm that takes into account the influence of slip along the interface between the old and new concrete layers is developed. In addition, the distribution of interfacial strain gradient, slip and shear stresses along the interface are predicted. A very good agreement is shown between the current proposed analytical model and the published experimental data on RC jacketed beams. Based on an extensive parametric study, effective flexural modification factors of these beams are developed and verified.