[This article belongs to Volume - 39, Issue - 05]

Structural Behavior of Pre-Damaged Reinforced Beam Strengthening by Ultra High Performance Concrete Overlay

Rebuilding damaged structures that already exist is one of the major issues facing civil engineers. To strengthen, repair, or retrofit these defects, common procedures include external pre-stressing, fiber-reinforced polymer wrapping, jacketing with steel and concrete, and patch repair. This study proposes using ultra-high-performance concrete strips as a strengthening material for the rehabilitation of damaged RC beams. UHPC provides high compressive strength, making it a highly desirable material in technical applications. A total of six reinforced concrete beams with a cross-section of 150 x 200 mm and a length of 1500 mm are tested under four-point loading to investigate their flexural behavior. This study assessed the flexural strength, stiffness, ductility, and energy absorption of preloaded beams to 60 and 75% of the average reference beam, and strengthened them with 50 mm UHPC strips containing three Glass Fiber Reinforced Polymer (GFRP) bars. Additionally, the study compares two techniques for casting the UHPC strips. The main test results The maximum load-carrying capacity of all tested specimens was largely greater than that of the control beams. Also, it widely enhances energy absorption with an increase in range (120–170%) from the average reference beam.