The 4th Asian Concrete Federation Symposium on Emerging Technologies for Structural Longevity (ACF2023- ETSL)

74 / 2022-04-13 09:19:05

Hybrid strengthening of concrete beams with shape memory alloy and carbon fiber reinforced polymer plates

CFRP, Concrete beams, Ductility, Hybrid strengthening, SMA

A novel hybrid strengthening approach that incorporates near-surface mounted shape memory alloys (SMAs) and externally bonded carbon fiber reinforced polymer (CFRP) has been proposed to strengthen concrete beams. Prestressing forces can be introduced to concrete because of the recovery stress of SMAs generated during heating activation, representing a quicker and more expedient prestressing technique compared to conventional prestressing techniques that usually necessitate hydraulic jacks. Three-point bending tests were performed to investigate the efficiency of this hybrid strengthening approach. The results show that the cracking, yielding, and ultimate moments can be considerably enhanced for the strengthened beam compared to the control beam. Furthermore, significant improvement in the displacement ductility can also be observed for the strengthened beam, which surmounts the issues associated with the compromised ductility for near-surface mounted or externally bonding CFRP. Therefore, this hybrid strengthening approach appears attractive for strengthening concrete structures, especially when the need for large ductility is valued.

A novel hybrid strengthening approach that incorporates near-surface mounted shape memory alloys (SMAs) and externally bonded carbon fiber reinforced polymer (CFRP) has been proposed to strengthen concrete beams. Prestressing forces can be introduced to concrete because of the recovery stress of SMAs generated during heating activation, representing a quicker and more expedient prestressing technique compared to conventional prestressing techniques that usually necessitate hydraulic jacks. Three-point bending tests were performed to investigate the efficiency of this hybrid strengthening approach. The results show that the cracking, yielding, and ultimate moments can be considerably enhanced for the strengthened beam compared to the control beam. Furthermore, significant improvement in the displacement ductility can also be observed for the strengthened beam, which surmounts the issues associated with the compromised ductility for near-surface mounted or externally bonding CFRP. Therefore, this hybrid strengthening approach appears attractive for strengthening concrete structures, especially when the need for large ductility is valued.