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Economic analysis of coating for reinforced concrete structures: Corrosion losses in infrastructure account for a large proportion of total corrosion losses, with those related to rebar corrosion making up approximately 40%–50%. In particular, the corrosion of reinforced concrete infrastructure, exemplified by bridges, has become a significant issue worldwide. Taking cross-sea bridges as an example, the investment budget for the Hangzhou Bay Bridge was 11.8 billion yuan, of which the cost associated with concrete coating amounted to over 100 million yuan, accounting for about 1% of the total investment. The designed service life of this bridge is 100 years. The Donghai Bridge, which has already been built, is also designed to last 100 years; however, cracks have begun to appear in it not long after it was put into use ； Including the Sutong Bridge, all face the serious problem of requiring coating protection. Conventional concrete in saline environments (without protective measures), although it has lower initial construction costs, requires its first repair after about 15 years; repairs are needed four times over a period of 40 years, and the cost of these repairs is approximately four times the initial construction cost (which is consistent with the actual situation of bridges in the United States). Based on experience, by selecting an appropriate coating scheme, the expected service life of the concrete protective coating on sea-crossing bridges can reach up to 60 years, while typical schemes also provide a lifespan of over 25 years. The maintenance period for concrete structures with coating protection can reach up to 50 years, while the standard approach typically results in a period of 25 years. In summary, it can be seen that by taking proactive protective measures, although the initial construction cost increases slightly (with painting costing 2% of the total cost under the best scenario), the total cost over 60 years is reduced by at least 40% compared to those who do not take such measures. Moreover, ensuring the safe passage of the bridge and reducing the social benefits associated with maintenance periods are also considerable.