Load-Bearing Performance of Non-Prismatic RC Beams Wrapped with Carbon FRP Composites

Area of Science:

• Civil Engineering
• Materials Science

Background:

• Non-prismatic reinforced concrete (RC) beams often exhibit complex structural behavior.
• Understanding the impact of strengthening techniques on these beams is crucial for infrastructure resilience.

Purpose of the Study:

• To investigate the influence of carbon fiber-reinforced polymer (CFRP) composite wrapping techniques on the load-deflection and strain responses of non-prismatic RC beams.
• To assess the effect of varying non-prismatic section lengths and the presence of openings on beam behavior and load capacity.

Main Methods:

• Twelve non-prismatic RC beams, with and without openings, were tested.
• Beams were strengthened using CFRP composites in strip or full wrap configurations.
• Load-deflection and strain responses were monitored using linear variable differential transducers and strain gauges.

Main Results:

• CFRP strengthening significantly enhanced performance, particularly in solid sections, reducing shear cracks and promoting ductile behavior.
• Strengthened beams showed 40-70% higher peak loads and up to 524.87% increase in ultimate deflection compared to control beams.
• Peak load improvement increased with non-prismatic section length; CFRP strip efficiency for ductility varied with length.

Conclusions:

• CFRP composite wrapping is an effective strengthening method for non-prismatic RC beams, improving both load capacity and ductility.
• The configuration and length of CFRP application influence the effectiveness of strengthening.
• CFRP-strengthened beams demonstrated superior load-strain capacity compared to unstrengthened control beams.