STM Article Repository

Steel bridges became popular in the early nineteenth century. Lead-containing coatings were used to protect the structures against uniform air deterioration. These have shown good resilience to deterioration throughout the years. Generally, a reduced corrosion as for the steel elements was also observed for the rivets, which linked the structural components. The damage was concentrated in areas that were directly exposed to rainfall or water flux. Crater development and exfoliation were only observed in isolated areas. The enrichment of organic deposits increased humidity stability, which had a negative impact on steel conservation. The total coating thickness fell marginally in these circumstances, and long-therm protection was no longer achieved. Lead's content has a negative impact on the environment. As a result, restoration efforts must take into account the pollutant's influence during removal and disposal. The present study outlines the main deterioration issues related to old steel bridges, which in general still exhibit a relatively good conservation state during time.