Iowa Department of Transportation
Iowa Highway Research Board
Behrouz Shafeishafei@iastate.edu email >
Structural Engineer, BEC
About the research
Several state departments of transportation (DOTs) are facing the daunting task of maintaining an inventory of corroding steel structures. Cold gas dynamic spraying (CS) is an innovative technique that can lead to substantial advances in the repair and retrofit of steel structures subjected to corrosive environments. The CS technique is believed to bring a wide spectrum of benefits, in terms of life-cycle performance and cost, to steel structures currently in service. In addition, the CS technique offers a durable treatment that can be simply applied with a portable device. This significantly expedites the repair process, resulting in minimized road closures and traffic disruptions.
When coated using the CS technique, steel members not only regain their lost structural capacity but also become more resistant to corrosion because the metal coating provides a strong yet passive layer against corrosive environments. This is an important advancement that greatly extends the expected life span of steel structural members without having to repeat maintenance actions every few years.
To achieve the ultimate goal of this exploratory project, a proof-of-concept study was carried out to evaluate the advantages of CS through a set of coupon tests to determine the corrosion resistance of structural steel with and without coating. The outcome not only demonstrates the promise of this emerging technique but can also be used to help tailor the CS process for transportation infrastructure applications for the very first time. This contribution will maximize the impact of this innovative technique, which holds great promise for future use and implementation.