Rapid and affordable repair technologies must be developed to rehabilitate the national infrastructure. In the case of steel infrastructure, corrosion and fatigue cracking have resulted in reduced load ratings. Composites technology represents one possible approach to rehabilitation, where composite patches are bonded to the steel substrate to transfer load through the damaged region. Key to success of this approach is to develop durable bonds between the steel and composite and to develop a rapid repair process. Immediate replacement is not economically viable.
Induction heating seems to be an ideal candidate.
The steel structures themselves can be used as a heating medium to cure thermoset adhesives or fusion bond thermoplastic composite patches. Induction heating offers a number of advantages for infrastructure rehabilitation. On-site repair and construction are possible using portable induction welders powered by portable generators. A short introduction on the fundamentals of induction heating is presented in Chapter 2 of this report, where important concepts like depth of penetration of the magnetic field and power generation are discussed. In Chapter 4, heat conduction in a semi-infinite slab was analyzed by simultaneously solving the mathematical problem and doing a Finite Element Analysis.