ABSTRACT
Based on the crack-stop holes, the Fe-based shape memory alloys (Fe-SMA) plates were used to repair fatigue cracks at the diaphragm cutouts of orthotropic steel deck (OSD) bridges, using its inherent stiffness and shape memory effect. In the experimental research, a total of 6 specimens were designed for fatigue test, including 2 specimens repaired solely by crack-stop holes and 4 specimens repaired by Fe-SMA plates. After completing the reinforcement, significant local stiffness and compressive stresses can be introduced at the edge of crack-stop holes, which can effectively reduce the stress concentration at the cracked region, postpone the initiation of fatigue cracks, and inhibit crack propagation after secondary-cracking. The fatigue life of specimens repaired by Fe-SMA plates is 3.73~12.68 times that of specimens repaired solely by crack-stop holes, indicating that bonding Fe-SMA plates based on crack-stop holes is an effective method for repairing cracked diaphragm cutouts in steel bridges.
