FLEXURAL STRENGTHENING OF STEEL BEAMS WITH PASSIVE AND ACTIVE CFRP PLATES

Advanced composites have become one of the most popular methods of repairing and/or strengthening civil infrastructure in the past couple of decades. While the use of CFRP laminates and sheets for the repair and strengthening of reinforced concrete structures is well established, research on the application of CFRP composites to steel structures has still been limited. However, the use of CFRP material for the repair and rehabilitation of steel members has numerous benefits over the traditional methods of bolting or welding of steel plates. The research work has been conducted to study the effect of strengthening steel I-beams using CFRP plates bonded to the tension flange. This research investigated experimentally the flexural behaviour of CFRP strengthened beams with passive and active (prestressed) systems. Flexural tests were carried out under 4-point bending on several medium scale steel beams. The effectiveness of strengthening has been established and the influence of various parameters on this effectiveness was investigated. This study also introduced the novel CFRP strip prestressing system for strengthening of steel beams.