Rehabilitation of Existing Structures Using CFRP

日期 : Aug 2017 - Jun 2018

While new reinforced concrete (RC) structures are being constructed at an incredible pace around the globe, existing structures seek periodic maintenance and damaged ones need necessary rehabilitation. The deterioration of existing structures might occur due to ageing of materials, environmental corrosion of embedded steel, inadequate quality of concrete, poor operations and maintenance, design deficiency, changes in use or imposed loading, fire damage, malpractices during construction, and natural calamities. The damaged structural members may be strengthened in flexure with the use of Carbon Fiber-Reinforced Polymer (CFRP) bonded to their tension zone using suitable epoxy as a common adhesive. In comparison to traditional rehabilitation techniques, for instance externally bonded steel plates, steel jackets, concrete jackets or external post-tensioning, CFRP wrapping has proved to be far more advantageous. With the intent to make CFRP jacketing familiar for rehabilitation technique particularly in the construction industry of Pakistan, an experimental study is carried out to economize the quantitative use of CFRP for rehabilitation of RC beams. The experimental program involves testing of three full-scale beams, having 7.5”x10.5” cross-section and 7.5’ clear span, under four-point bending. A comparative analysis between beams fully and selectively jacketed with CFRP in U-shape configuration has been drawn. To simulate degradation of structural members in real-time, two beams are first loaded to 65% of ultimate strength, unloaded, and then wrapped before testing